Methods for producing metallocene complexes having hydrocarbyl leaving groups

Abstract

Methods for forming Group 4 metal bridged bis(metallocene) complexes having two hydrocarbyl leaving groups comprising: contacting a Group 4 metal tetrahalide and a metal hydrocarbyl reagent in an ether solvent, thereby forming a first reaction product in a first mixture; and without isolating the first reaction product, combining the first mixture with a dilithium salt of a bridged bis(cyclopentadienyl) compound, thereby forming in a second mixture a second reaction product comprising a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups. The Group 4 metal may be zirconium or hafnium. The hydrocarbyl leaving groups may be C1-C10 alkyl groups. Catalyst systems may comprise the Group 4 metal bridged bis(metallocene) complexes having two hydrocarbyl leaving groups, an activator, and optionally a support. Polymerization processes may comprise: providing an olefinic feed; and contacting the catalyst system with the olefinic feed under polymerization reaction conditions to produce a polyolefin.

Description

2025EM046-WG / 050930-0691METHODS FOR PRODUCING METALLOCENE COMPLEXES HAVING HYDROCARBYL LEAVING GROUPSFIELD

[0001] The present disclosure relates to olefin polymerization, and more particularly, to one-pot methods for preparing metallocene complexes and catalyst systems thereof.BACKGROUND

[0002] Metallocene catalyst systems may be used for polymerizing alpha olefins. Metallocene catalyst systems may be prepared by combining a metallocene complex, an activator, an optional co-activator, and an optional support material, such as a silica support. Activators include substances such as alumoxanes (e.g., methylalumoxane (MAO)) or non-coordinating anion activators. Co-activators include substances such as trialkylaluminum compounds. Collectively, the activator and optional co-activator transform the metallocene complex into a form that is active for promoting polymerization of alpha olefins. Without being bound by theory or mechanism, MAO and trimethylaluminum may perform an equilibrium exchange of halide ligands (e.g., chloride ligands) in a dihalide metallocene complex, a commonly produced form of metallocene complexes, to introduce methyl groups in place of the halide ligands. After loss of a methyl ligand, the demethylated metallocene complex is believed to be the active catalyst species for promoting olefin polymerization. Incomplete exchange of the halide ligands may occur during activation and lead to catalytic activities that are lower than desired.SUMMARY

[0003] According to embodiments consistent with the present disclosure, methods comprise: contacting a Group 4 metal tetrahalide and a metal hydrocarbyl reagent in an ether solvent, thereby forming a first reaction product in a first mixture; and without isolating the first reaction product, combining the first mixture with a dilithium salt of a bridged bis(cyclopentadienyl) compound, thereby forming a second reaction product in a second mixture, the second reaction product comprising a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups.

[0004] These and other features and attributes of the disclosed systems and methods of the present disclosure and their advantageous applications and / or uses will be apparent from the detailed description which follows.2025EM046-WG / 050930-0691BRIEF DESCRIPTION OF THE DRAWINGS

[0005] To assist those of ordinary skill in the relevant art in making and using the subject matter hereof, reference is made to the appended drawings. The following figures are included to illustrate certain aspects of the disclosure, and should not be viewed as exclusive configurations. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.

[0006] The FIGURE shows proton nuclear magnetic resonance (1H NMR) spectra of Complex Cl and Complex II after reaction with MAO.DETAILED DESCRIPTION

[0007] The present disclosure relates to olefin polymerization, and more particularly, to one-pot methods for preparing metallocene complexes and catalyst systems thereof.

[0008] The present disclosure provides methods that may alleviate certain difficulties associated with activation of metallocene complexes for performing olefin polymerization. In particular, the present disclosure provides methods for preparing metallocene complexes having dihydrocarbyl ligands in a single reaction mixture ( / .<., via a “one-pot” reaction) without the need to isolate a dihalide (e.g., dichloride) metallocene complex as an intermediate and subsequently perform ligand exchange prior to activation. Obtaining a metallocene complex having hydrocarbyl ligands directly via a single reaction mixture may afford advantages over the corresponding dihalide metallocene complexes in terms of improved activation performance with activators such as MAO, leading to higher catalytic activities in olefin polymerization, such as during propylene polymerization.Definitions

[0009] For the purposes of the present disclosure, the new numbering scheme for groups of the Periodic Table is used. In said numbering scheme, the groups (columns) are numbered sequentially from left to right from 1 through 18, excluding the f block elements (lanthanides and actinides). Under this scheme, the term “transition metal” refers to any atom from Groups 3-12 of the Periodic Table, inclusive of the lanthanide and actinide elements. Ti, Zr, and Hf are Group 4 transition metals (or equivalently, Group 4 metals), for example. A metallocene containing a Group 4 metal may be referred to herein as a Group 4 metallocene.2025EM046-WG / 050930-0691

[0010] The terms “metallocene,” “metallocene complex,” and “metallocene compound” are used interchangeably herein to refer to an organometallic compound having a transition metal center (M) 7i-bound to at least one optionally substituted cyclopentadienyl moiety, preferably to two optionally substituted cyclopentadienyl moieties.

[0011] The term “metallocene catalyst system” refers to the combination of a metallocene complex, at least one activator, an optional co-activator, and an optional support material.

[0012] The term “independently,” when referencing a selection of multiple items from within a given group, means that the selected choice for a first item does not necessarily influence the choice of any second or subsequent item. That is, independent selection of multiple items within a given group means that the individual items may be the same as or different from one another.

[0013] The terms “group,” “radical,” and “substituent” may be used interchangeably herein.

[0014] The term “hydrocarbon” refers to a class of compounds having hydrogen bound to carbon, and encompasses saturated hydrocarbon compounds, unsaturated hydrocarbon compounds, and mixtures of hydrocarbon compounds (saturated and / or unsaturated), including mixtures of hydrocarbon compounds having different numbers of carbon atoms. The term “Cn” refers to hydrocarbon(s) or a hydrocarbyl group having n carbon atom(s) per molecule or group, wherein n is a positive integer. Such hydrocarbon compounds may be one or more of linear, branched, cyclic, acyclic, saturated, unsaturated, aliphatic, and / or aromatic. As used herein, a cyclic hydrocarbon may be referred to as “carbocyclic,” which includes saturated, unsaturated, and partially unsaturated carbocyclic compounds, as well as aromatic compounds The term “heterocyclic” refers to a carbocyclic ring containing at least one ring heteroatom as a replacement for a ring carbon atom.

[0015] The terms “hydrocarbyl radical,” “hydrocarbyl,” and “hydrocarbyl group” may be used interchangeably throughout this disclosure and refer to a group containing hydrogen atoms and carbon atoms and bearing at least one unfilled valence position when removed from a parent compound. Hydrocarbyl radicals may be optionally substituted in some cases. Suitable “hydrocarbyl radicals” may refer to Ci-Cioo radicals that may be linear, branched, or cyclic, and when cyclic, aromatic or non-aromatic in nature. Examples of saturated hydrocarbyl radicals include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tertbutyl, pentyl, iso-amyl, hexyl, octyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, and the like, including their substituted analogues.2025EM046-WG / 050930-0691

[0016] Substituted hydrocarbyl radicals are radicals in which at least one hydrogen atom of the hydrocarbyl radical has been substituted with at least a non-hydrogen group, such as a hydrocarbyl group, a halogen (e.g., Br, Cl, F or I), or at least one functional group such as NR*, OR*, SeR*, TeR*, PR*2, ASR*2, SbR*2, SR*, BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like, or where at least one heteroatom has been inserted within a hydrocarbyl ring or chain, wherein each R* is independently hydrogen, a hydrocarbyl or halocarbyl radical, or two or more R* may join together to form an optionally substituted, saturated, unsaturated, partially unsaturated, or aromatic cyclic or polycyclic ring structure.

[0017] The term “optionally substituted” means that a hydrocarbon or hydrocarbyl group can be unsubstituted or substituted. For example, the term “optionally substituted hydrocarbyl” refers to replacement of at least one hydrogen atom or carbon atom in a hydrocarbyl group with a heteroatom or heteroatom functional group. Unless otherwise specified as being expressly unsubstituted, any of the hydrocarbyl groups herein may be optionally substituted.

[0018] The term “substituted” refers to replacement of at least one hydrogen atom or carbon atom of a hydrocarbon or hydrocarbyl group with a heteroatom or heteroatom functional group. Heteroatoms may include, but are not limited to, B, O, N, S, P, F, Cl, Br, I, Si, Pb, Ge, Sn, As, Sb, Se, and Te. Heteroatom functional groups that may be present in substituted hydrocarbons or hydrocarbyl groups include, but are not limited to, functional groups such as O, S, S=O, S(=O)2, NO2, F, Cl, Br, I, NR2, OR, SeR, TeR, PR2, AsR2, SbR2, SR, BR2, SiR3, GeR3, SnR3, PbR3, where R is a hydrocarbyl group or H. Suitable hydrocarbyl R groups may include alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, heterocyclyl, and the like, any of which may be optionally substituted.

[0019] The term “saturated hydrocarbon” means a hydrocarbon that contains zero carbon-carbon double bonds or carbon-carbon triple bonds. The saturated hydrocarbon can be a linear or cyclic hydrocarbon, either of which may be optionally branched. The saturated hydrocarbon can be a C2-C40 hydrocarbon, such as a C4-C7 hydrocarbon. In at least one embodiment, a C4-C7 hydrocarbon may be isobutane, pentane, cyclopentane, cyclohexane, isopentane, isohexane, hexane, heptane, or mixtures thereof.

[0020] The term “alkyl” means a straight chain, branched chain, or cyclic hydrocarbon radical having only carbon-carbon single bonds. Such alkyl radicals may be optionally substituted. Examples of alkyl radicals include, but are not limited to, methyl, ethyl, n propyl, isopropyl, n2025EM046-WG / 050930-0691butyl, isobutyl, sec butyl, tert butyl, pentyl, iso amyl, hexyl, octyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, and the like, including their substituted analogues.

[0021] The term “alkoxide” means entities containing a C1-C40 hydrocarbyl group bound to oxygen. The hydrocarbyl group may be straight chain, branched, or cyclic, and be saturated or unsaturated, including aromatic. The terms “alkoxy” and “alkoxide” therefore refer to an alkyl ether or aryl ether radical. Examples of hydrocarbyl ether radicals include, but are not limited to, methoxy, ethoxy, n propoxy, iso propoxy, n butoxy, iso butoxy, sec butoxy, tert butoxy, phenoxy, and the like.

[0022] The term “alkylene” means a divalent alkyl radical. For example, a methylene group is a divalent alkylene radical.

[0023] The term “olefin” (alternately referred to as “alkene”) means a linear, branched, or cyclic compound of carbon and hydrogen having at least one carbon-carbon bond.

[0024] The term “alkenyl” means a straight chain, branched chain, or cyclic hydrocarbon radical having one or more carbon-carbon double bonds. The alkenyl radicals may be optionally substituted. Examples of suitable alkenyl radicals include, but are not limited to, ethenyl, propenyl, allyl, 1,4 butadienyl, cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloctenyl, and the like, including their substituted analogues.

[0025] The term “aromatic” means a hydrocarbyl compound or group containing a planar unsaturated ring of atoms that is stabilized by interaction of the bonds forming the ring. Such compounds are often six membered rings such as benzene and its derivatives. As used herein, the term “aromatic” also refers to pseudoaromatics which are compounds that have similar properties and structures (nearly planar) to aromatics, but are not by definition aromatic; likewise, the term aromatic also refers to substituted aromatic compounds and radicals. Aromatic (but not pseudoaromatic) hydrocarbons obey the Hiickel Rule and contain a cyclic cloud of 4n+2 n electrons, where n is a positive integer.

[0026] The term “aryl” or “aryl group” means a carbon-containing aromatic ring or substituted variants thereof, including but not limited to, phenyl, 2 methylphenyl, xylyl, 4 bromoxylyl, and the like. Likewise, the term “heteroaryl” or “heteroaryl group” means an aryl group where a ring carbon atom (or two or three ring carbon atoms) has been replaced with a heteroatom, preferably N, O, or S. As used herein, the term “aromatic” also refers to pseudoaromatic heterocycles which2025EM046-WG / 050930-0691are heterocyclic substituents that have similar properties and structures (nearly planar) to aromatic heterocyclic groups but are not by definition aromatic.

[0027] A substituted aryl is an aryl group where at least one hydrogen atom of the aryl radical has been substituted with at least a non-hydrogen group, such as a hydrocarbyl group, a heteroatom, or a heteroatom containing group, such as halogen (e.g., Br, Cl, F or I) or at least one functional group such as NR*2, OR*, SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, BR*2, SiR*, SiR*3, GeR*, GeR*3, SnR*, SnR*3, PbR*3, and the like, where each R* is independently hydrogen, a hydrocarbyl or halocarbyl radical, or two or more R* may join together to form an optionally substituted, saturated, unsaturated, partially unsaturated, or aromatic cyclic or polycyclic ring structure, or where at least one heteroatom has been inserted within a hydrocarbyl ring. For example, 3,5-dimethylphenyl and 2-methylphenyl are substituted aryl groups. The term “arylalkyl” may also refer to an aryl group where a hydrogen has been replaced with an alkyl or substituted alkyl group. The term “alkylaryl” means an alkyl group where a hydrogen has been replaced with an aryl or substituted aryl group. Thus, for example, 2-methylphenyl is an arylalkyl or substituted aryl group, and benzyl and phenethyl are alkylaryl groups. Benzyl and phenethyl may alternately be considered to constitute substituted alkyl groups.

[0028] Any aryl group herein may be an optionally substituted phenyl group. The term “substituted phenyl,” or “substituted phenyl group” means a phenyl group having one or more hydrogen groups replaced by a hydrocarbyl, substituted hydrocarbyl, heteroatom, or heteroatom containing group, such as halogen e.g., F, Cl, Br, I) or at least one functional group such as NR*2, OR*, SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, BR*2, SiR*, SiR*3, GeR*, GeR*3, SnR*, SnR*3, PbR*3, and the like, where each R* is independently hydrogen, a hydrocarbyl, halogen, or halocarbyl radical, or two or more R* may join together to form an optionally substituted, saturated, unsaturated, partially unsaturated, or aromatic cyclic or polycyclic ring structure, or where at least one heteroatom has been inserted within a hydrocarbyl ring.

[0029] The term “heterocyclic” means a cyclic group where a ring carbon atom (or two or three ring carbon atoms) has been replaced with a heteroatom, such as N, O, or S. A heterocyclic ring is a ring having a heteroatom in the ring structure as opposed to a heteroatom substituted ring where a hydrogen on a ring atom is replaced with a heteroatom. For example, tetrahydrofuran is a heterocyclic ring, and 4-N, N-dimethylaminophenyl is a heteroatom substituted ring.2025EM046-WG / 050930-0691

[0030] The term “substituted heterocyclic” means a heterocyclic group where at least one hydrogen atom of the heterocyclic radical has been substituted with at least a non-hydrogen group, such as a hydrocarbyl group, a heteroatom, or a heteroatom containing group, such as halogen (e.g., F, Cl, Br, I) or at least one functional group such as NR*2, OR*, SeR*, TeR*, PR*2, ASR*2, SbR*2, SR*, BR*2, SiR*, SiR*3, GeR*, GeR*3, SnR*, SnR*3, PbR*3, and the like, where each R* is independently hydrogen, a hydrocarbyl or halocarbyl radical.

[0031] The term “ring atom” means an atom that is part of a cyclic ring structure. By this definition, a benzyl group has six ring atoms and tetrahydrofuran has five ring atoms.

[0032] For purposes of this disclosure, when a polymer, copolymer, or oligomer, particularly a polyolefin, is referred to as comprising an olefin, the olefin present in such polymer, copolymer, or oligomer is the polymerized form of the olefin. For example, when a copolymer is said to have an “ethylene” content of 0 wt% to 5 wt%, it is to be understood that the mer unit in the copolymer is derived from the monomer ethylene in the polymerization reaction and said derived units are present at 0 wt% ( / .<?., absent) to 5 wt%, based upon the weight of the copolymer. As used herein, the terms “polymer” and oligomer” (and grammatical variations thereof) are used interchangeably to refer to a molecule having two or more of the same or different mer units. As used herein, the term “polymerize” (and grammatical variations thereof, e.g., polymerization) is used to refer to a process of generating a molecule having two or more of the same or different mer units from two or more of the same or different monomers. A “homopolymer” is a polymer (or oligomer) having mer units that are the same. A “copolymer” is a polymer (or oligomer) having two or more mer units that are different from each other. A “terpolymer” is a polymer (or oligomer) having three mer units that are different from each other. “Different,” as used to refer to mer units, indicates that the mer units differ from each other by at least one atom or are different isomerically. Accordingly, the definition of copolymer, as used herein, includes terpolymers and like higher polymers (or oligomers). A “decene polymer” or “decene copolymer,” for example, is a polymer or copolymer comprising at least 50 mol% decene derived units.

[0033] The term “catalyst productivity” is a measure of the mass of polymer produced using a known quantity of polymerization catalyst. Typically, catalyst productivity is expressed in units of (g of polymer) / (g of catalyst) or (g of polymer) / (mmols of catalyst) or the like. If units are not specified, then the “catalyst productivity” is in units of (g of polymer) / (grams of catalyst). For2025EM046-WG / 050930-0691calculating catalyst productivity, only the weight of the transition metal component of the catalyst is used (z.e., the activator and / or co-activator is omitted).

[0034] The term “catalyst activity” is a measure of the mass of polymer produced using a known quantity of polymerization catalyst per unit time for batch and semi-batch polymerizations. For calculating catalyst activity, only the weight of the transition metal component of the catalyst is used (i.e., the activator and / or co-activator is omitted). Typically, “catalyst activity” is expressed in units of (g of polymer) / (mmol of catalyst) / hour or (kg of polymer) / (mmols of catalyst) / hour or the like. If units are not specified, then the “catalyst activity” is in units of (g of polymer) / (mmol of catalyst) / hour.

[0035] For nomenclature purposes, the following numbering scheme is used for an indenyl ring. It should be noted that an indenyl ring can be considered a cyclopentadienyl group fused with a benzene ring. The structure below is drawn and named as an anion.Indenyl

[0036] Also, for clarity, the following ring structures are substituted indenyl groups, where substitutions at the 5- and 6- positions collectively define a ring structure. A similar numbering and nomenclature scheme is used for these types of substituted indenyls that include indacenyls, cyclopenta[b]naphthalenyls, heterocyclopentanaphthyls, heterocyclopentaindenyls, and the like, as illustrated below. Each structure is drawn and named as an anion.1,2,3-trihydro-s-indacenyl 5,6,7,8-tetrahydro-cyclopenta[ / ?]naphthalenyl2025EM046-WG / 050930-06917,8-dihydro-cyclopenta[ / >]naphthalenyl

[0037] Where isomers of a named alkyl, alkenyl, alkoxide, or aryl group exist (e.g., n-butyl, isobutyl, sec-butyl, and tert-butyl), reference to one member of the group (e.g., n-butyl) shall expressly disclose the remaining isomers e.g., iso-butyl, sec-butyl, and tert-butyl) in the family. Likewise, reference to an alkyl, alkenyl, alkoxide, or aryl group without specifying a particular isomer (e.g., butyl) expressly discloses all isomers (e.g., n-butyl, iso-butyl, sec-butyl, and tertbutyl).

[0038] When used in the present disclosure, the following abbreviations may be used: dme is 1,2 dimethoxyethane, Me is methyl, Ph is phenyl, Et is ethyl, Pr is propyl, iPr is isopropyl, n Pr is normal propyl, cPr is cyclopropyl, Bu is butyl, iBu is isobutyl, tBu is tertiary butyl, p-tBu is para-tertiary butyl, nBu is normal butyl, sBu is sec butyl, TMS is trimethyl silyl, TIBAL is triisobutylaluminum, TNOAL is tri(n-octyl)aluminum, MAO is methylalumoxane, sMAO is supported methylalumoxane, Bn is benzyl (i.e., CH2PI1), THF is tetrahydrofuran, RT is room temperature (and is 23°C unless otherwise indicated), tol is toluene, EtOAc is ethyl acetate, and Cy is cyclohexyl.Metallocene Complexes

[0039] The Group 4 metal bridged metallocene complexes utilized herein may have Cl symmetry (i.e., belong to a Cl point group). Such metallocene complexes may afford a number of advantages during olefin polymerization. Because they are asymmetric, the Group 4 metal bridged metallocene complexes have no planes of symmetry about any axis. The asymmetry is advantageous as no isomers (rac / meso) are formed during synthesis, thereby providing a much higher yield of usable metallocene complexes relative to other metallocene complexes that are2025EM046-WG / 050930-0691symmetric but are capable of forming optical isomers. That is, Group 4 metal bridged metallocene complexes having Cl symmetry may be advantageous in terms of subverting the need to separate optical isomers. This feature may be particularly beneficial in view of the in situ formation of the dialkylated form of the Group 4 metal bridged metallocene complexes in accordance with the disclosure herein.

[0040] The Group 4 metal bridged metallocene complexes may have a Group 4 metal (e., Ti, Zr, or Hf) bonded to each of the cyclopentadienyl moieties, as to two hydrocarbyl leaving groups. The Group 4 metal bridged metallocene complexes may have a structure represented by Formula 1 belowR9R8Formula 1wherein:

[0041] M is the Group 4 metal, Zr, Hf, or Ti, preferably Zr or Hf, and more preferably Zr;

[0042] T is a bridging group;

[0043] X1and X2are each independently an optionally substituted Ci-Cio hydrocarbyl; preferably an optionally substituted Ci-Cio alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl;

[0044] R1is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14aryl, optionally substituted C3-C13 heteroaryl, -NR'2, -SR', -OR', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, where R" is C1-C10 alkylene and each R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; preferably, R1is C1-C10 alkyl, and more preferably, R1is methyl;

[0045] R2and R6are independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, an optionally substituted C3-C13 heteroaryl, -NR'2, -SR', -OR', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene2025EM046-WG / 050930-0691and each R1is hydrogen, Ci-Cio alkyl, or C6-C10aryl; preferably, at least one of R2and R6are hydrogen, and more preferably, R2and R6are both hydrogen;

[0046] R3is an optionally substituted C1-C40 alkyl, an optionally substituted Ce-Cis aryl, or an optionally substituted C3-C13 heteroaryl; more preferably R3is a bulky alkyl group, such as an optionally substituted cyclohexyl, an optionally substituted norbornanyl, an optionally substituted adamantanyl, or an optionally substituted tert-butyl, such as cyclohexyl, 1-adamantyl, 2-adamantyl, (ls,4s)-bicyclo[2.2.1]heptan-7-ide, (lR,4S)-bicyclo[2.2.1]heptan-2-ide, or (ls,4s)-bicyclo[2.2.1]heptan-l-ide; or R3is an optionally substituted aryl group, more preferably an optionally substituted phenyl group; even more preferably, R3is an optionally substituted phenyl group, an optionally substituted naphthyl group, or an optionally substituted anthracenyl group;

[0047] R4and R3are independently H, R1", or OR'", wherein R1" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof; and

[0048] R7, R8, R9, and R10are independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, optionally substituted C3-C13 heteroaryl, -NR'2, -SR', -OR', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R7and R8, R8and R9, or R9and R10are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof; preferably R7, R8, R9, and R10are methyl.

[0049] As a non-limiting illustration, in Formula 1 when R4and R5are joined to form a polycyclic ring structure, the polycyclic ring structure may comprise a 5- or 6-membered ring, preferably a 5- or 6-membered carbocyclic ring lacking heteroatoms as ring atoms. For example, an indacenyl ligand contains such a 5-membered carbocyclic ring and a hexahydrobenz[ / ]indenyl ligand contains such a 6-membered carbocyclic ring, as shown below:hexahydrobenz[ / ]indenyl ligand

[0050] The carbocyclic ring in the indacenyl ligand or the hexahydrobenz[f]indenyl ligand can be optionally substituted and can be part of multi-cyclic groups where the additional cyclic groups may be saturated or unsaturated, and optionally substituted. Typical substituents on the carbocyclic ring may include optionally substituted Ci to C40 hydrocarbyls, heteroatoms (such as halogens, including Br, F, Cl, or I), heteroatom-containing groups (such as a halocarbyl), or two or more substituents are joined together to form a cyclic or polycyclic ring structure (which may contain saturated and / or unsaturated rings), or a combination thereof. One or more of such substituents may be present. Example ligands in which R4and R5are fused to form a carbocyclic ring include those having structures represented by Formulas 2-4:Formula 2 Formula 3 Formula 4 where the wavy lines indicate a connection to M in Formula 1 (such as to Zr or Hf) and T (such as Me2Si or Ph2Si). The corresponding ligands lacking methyl group substitution on the unsaturated carbocyclic ring are also suitable for use herein. In any of the foregoing, R3may be a bulky alkyl group, preferably an optionally substituted cyclohexyl, optionally substituted norbornanyl, optionally substituted adamantyl, or optionally substituted tert-butyl, or an optionally substituted aryl group, such as an optionally substituted phenyl group. In any of the foregoing, R3may preferably be an optionally substituted phenyl group, optionally substituted naphthyl group, or optionally substituted anthracenyl group.2025EM046-WG / 050930-0691

[0051] When R4and R5are not joined to form a polycyclic ring structure, preferably both R4and R5may be hydrogen, or R4may be OR'" and R5may be R1", wherein each R1" is independently selected. In specific examples, R4may be OR'", preferably OCH3 and R5may be hydrogen.

[0052] In some embodiments, T is represented by the formula, (R*2G)g, wherein each G is C, Si, or Ge, g is 1 or 2, and each R* is, independently, hydrogen, an optionally substituted C1-C20 hydrocarbyl (such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, or phenyl), or the two or more R* are joined to form an optionally substituted, saturated, partially unsaturated or aromatic, cyclic or polycyclic ring structure. In some embodiments, the bridging group may be represented by R'2C, R'2Si, R'2Ge, R'2CCR'2, R'2CCR'2CR'2, R'2CCR'2CR'2CR'2, R'C=CR', R'C=CR'CR’2, R'2CCR'=CR'CR'2, R'C=CR'CR'=CR', R'C=CR'CR'2CR’2, R'2CSiR'2, R'2SiSiR'2, R'2CSiR'2CR'2, R'2SiCR'2SiR'2, R'C=CR'SiR'2, R'2CGeR'2, R'2GeGeR'2, R^CGeR^CR^, R^GeCR^GeR^, R^SiGeR^, R'C=CR'GeR'2, R'B, R'2C-BR’,R'2C-BR'-CR'2, R'2C-O-CR'2, R'2CR'2C-O-CR'2CR'2, R'2C-O-CR'2CR'2, R'2C-O-CR'=CR', R'2C-S-CR'2, R'2CR'2C-S-CR'2CR'2, R'2C-S-CR'2CR'2, R'2C-S-CR'=CR', R'2C-Se-CR'2, R'2CR'2C-Se-CR'2CR'2, R'2C-Se-CR'2CR'2, R'2C-Se-CR'=CR', R'2C-N=CR', R'2C-NR'-CR'2, R'2C-NR'-CR'2CR'2, R'2C-NR'-CR'=CR', R'2CR'2C-NR'-CR'2CR'2, R’2C-P=CR', or R'2C-PR'-CR'2where each R' is independently hydrogen or an optionally substituted C1-C20 hydrocarbyl (such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, or phenyl), a C1-C20 halocarbyl, a C1-C20 silylcarbyl, or a C1-C20 germylcarbyl substituent, or two or more adjacent R' are joined to form an optionally substituted, saturated, partially unsaturated or aromatic, cyclic or polycyclic ring structure. In some embodiments of the present disclosure, T may be CH2, CH2CH2, C(CH3)2, (Ph)2C, (p-(Et)3SiPh)2C, SiMe2, SiPh2, SiMePh, Si(CH2)3, or Si(CH2)4. Preferably, T is CH2or SiMe2, and more preferably SiMe2or SiPh2.

[0053] Suitable alkyl groups in any selection herein may be optionally substituted and independently chosen from, but not limited to, methyl, ethyl, ethenyl and isomers of propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, heneicosenyl,2025EM046-WG / 050930-0691docosenyl, tricosenyl, tetracosenyl, pentacosenyl, hexacosenyl, heptacosenyl, octacosenyl, nonacosenyl, triacontenyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, decynyl, undecynyl, dodecynyl, tridecynyl, tetradecynyl, pentadecynyl, hexadecynyl, heptadecynyl, octadecynyl, nonadecynyl, eicosynyl, heneicosynyl, docosynyl, tricosynyl, tetracosynyl, pentacosynyl, hexacosynyl, heptacosynyl, octacosynyl, nonacosynyl, triacontynyl, butadienyl, pentadienyl, hexadienyl, heptadienyl, octadienyl, nonadienyl, and decadienyl.

[0054] Suitable aryl groups in any selection herein may be optionally substituted and independently chosen from, but not limited to, phenyl, 1 -naphthyl, 2-naphthyl, 9-anthracenyl, 2-biphenyl, 3-biphenyl, 4-biphenyl, 2-methylphenyl, 3 -methylphenyl, 4-methylphenyl, 2.3 -dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3.4-dimethylphenyl, 3,5-dimethylphenyl, 2,4,5-trimethylphenyl, 3,4,5-trimethylphenyl, 2,3,4,5,6-pentamethylphenyl, 2-ethylphenyl, 3 -ethylphenyl, 4-ethylphenyl, 2,3-diethylphenyl, 2.4-diethylphenyl, 2,5-diethylphenyl, 2,6-diethylphenyl, 3,4-diethylphenyl, 3,5-diethylphenyl, 2-isopropylphenyl, 3-isopropylphenyl, 4-isopropylphenyl, 3,5-di-isopropylphenyl, 2.5-di-isopropylphenyl, 2-tert-butylphenyl, 3-tert-butylphenyl, 4-tert-butylphenyl, 3.5-di-tert-butylphenyl, 3,5-di-tert-butyl-4-methoxyphenyl, 3.5-di-tert-butyl-4-dimethylaminophenyl, 2,5-di-tert-butylphenyl, 2-trimethylsilylphenyl, 3-trimethylsilylphenyl, 4-trimethylsilylphenyl, 3,5-bis(trimethylsilyl)phenyl, 2 -trifluoromethylphenyl, 3 -trifluoromethylphenyl, 4-trifluorom ethylphenyl, and 3.5-bis(trifluoromethyl)phenyl.

[0055] Suitable cycloalkyl groups in any selection herein may be optionally substituted and independently chosen from, but not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, cycloheptyl, norbomanyl, adamantyl and the like.

[0056] In more specific examples, suitable metallocene complexes may have a structure represented by Formula 1 and a bulky alkyl substitution at R3which may include variables defined in accordance with the following:

[0057] M is zirconium or hafnium, preferably zirconium;

[0058] T is a bridging group; preferably, CRnR12or SiRnR12, wherein R11and R12are independently hydrogen, an optionally substituted C1-C40 hydrocarbyl, or an optionally substituted C6-C62 aryl, or R11and R12are joined to form an optionally substituted C4-C62 saturated or unsaturated cyclic or polycyclic ring structure; more preferably T is CH2, CH2CH2, C(CH3)2,2025EM046-WG / 050930-0691(Ph)2C, (p-(Et)3SiPh)2C, SiMe2, SiPh2, SiMePh, Si(CH2)3, Si(CH2)4, or Si(CH2)4; still more preferably T is CH2or SiMe2or more preferably, T is SiMe2or SiPh2;

[0059] X1and X2are each independently an optionally substituted Ci-Cio hydrocarbyl; preferably an optionally substituted Ci-Cio alkyl; more preferably an optionally substituted Ci-Ce or C6-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl;

[0060] R1is hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2aryl, an optionally substituted C4-Ce2 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is Ci-Cio alkylene and R' is hydrogen, Ci-Cio alkyl, or C6-C10aryl; preferably, R1is Ci-Cio alkyl; more preferably, R1is methyl;

[0061] R2and R6are independently hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2aryl, an optionally substituted C4-Ce2heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is Ci-Cio alkylene and R' is hydrogen, Ci-Cio alkyl, or C6-C10aryl; preferably R2is hydrogen; preferably R2and R6are each hydrogen, or R2is hydrogen and R6is hydrogen or optionally substituted phenyl;

[0062] R3is a bulky alkyl group; preferably R3is an optionally substituted cyclohexyl, optionally substituted norbornanyl, optionally substituted adamantyl (e.g., 1-adamantyl, 2-adamantyl, (ls,4s)-bicyclo[2.2.1]heptan-7-yl, (lR,4S)-bicyclo[2.2.1]heptan-2-yl, (ls,4s)-bicyclo[2.2.1]heptan-l-yl), or optionally substituted t-butyl;

[0063] R4and R5are independently H, R'", or OR'", wherein R'" is an optionally substituted Ci-C4o alkyl, or R4and R5are joined to form a C3-C62optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof; and

[0064] R7, R8, R9, and R10are independently hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2aryl, an optionally substituted C4-Ce2 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R5and R6, R6and R7, or R7and R8are joined to form an optionally substituted C4-Cr)2saturated or unsaturated cyclic or polycyclic ring structure, or a combination thereof; preferably R5, R6, R7, and R8are each C1-C10 alkyl; more preferably R5, R6, R7, and R8are each methyl.2025EM046-WG / 050930-0691

[0065] If R4and R are not joined to form a cyclic or polycyclic ring structure, preferably both R4and R5may be hydrogen, or R4may be OR'" and R5may be R'", wherein each R"' is independently selected. In specific examples, R4may be OR'", preferably OCH3, and R5may be hydrogen, or R4may be OR'", preferably OCH3, and R5may be an alkyl group, preferably t-butyl.

[0066] Accordingly, in some embodiments, suitable metallocenes having Cl symmetry may have a structure represented by Formula 5Formula 5wherein:

[0067] M is a Group 4 metal, preferably Zr or Hf, more preferably Zr;

[0068] X1and X2are each independently an optionally substituted C1-C10 hydrocarbyl; preferably an optionally substituted C1-C10 alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl;

[0069] R1is C1-C10 alkyl group, preferably methyl;

[0070] R3is a bulky alkyl group, preferably optionally substituted cyclohexyl, optionally substituted norbomanyl, optionally substituted adamantyl, or optionally substituted t-butyl; preferable groups include 1-adamantyl, 2-adamantyl, (ls,4s)-bicyclo[2.2.1]heptan-7-ide, (lR,4S)-bicyclo[2.2.1]heptan-2-ide, or (ls,4s)-bicyclo[2.2.1]heptan-l-ide;

[0071] R4and R3are independently H, R'", or OR'", wherein R'" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof;

[0072] R6is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, an optionally substituted C3-C13 heteroaryl, -NR'2, -SR', -OR',2025EM046-WG / 050930-0691-SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and each R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; preferably R6is hydrogen or optionally substituted phenyl;

[0073] R7, R8, R9, and R10are independently hydrogen, a halogen, an optionally substituted C1-C40 hydrocarbyl, an optionally substituted C4-C62 aryl, an optionally substituted C4-C62 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R5and R6, R6and R7, or R7and R8are joined to form an optionally substituted C4-C62 saturated or unsaturated cyclic or polycyclic ring structure, or a combination thereof; preferably R3, R6, R7, and R8are each C1-C10 alkyl; more preferably R3, R6, R7, and R8are each methyl; and

[0074] R11and R12are independently optionally substituted C1-C10 alkyl, or optionally substituted C6-C10aryl, or R11and R12are joined to form an optionally substituted C2-C22 saturated or unsaturated cyclic or polycyclic ring structure; preferably, R11and R12are each methyl or phenyl, and more preferably, R11and R12are each methyl.

[0075] In some examples, R4and R5may form a 5-membered carbocyclic ring. Specific examples of such metallocenes having a bulky alkyl group at R3and having R4and R3fused as a 5-membered carbocyclic ring may have a structure represented by Formula 6A, preferably wherein R6is hydrogen or optionally substituted phenyl, and more preferably wherein R6is hydrogen. The metallocene represented by Formula 6B lacks the 5-membered carbocyclic ring fused to theR9R8Formula 6Bwherein in Formula 6A:

[0076] Q is an optional Ci-Ce alkyl group, and q is 0, 1, 2, 3, 4, 5, or 6. When present (q 0), optional substitution Q may be present at any non-aromatic carbon atom of the 5-membered ring defined by R4and R3. Preferably, each occurrence of Q is a methyl group. The other variables are defined as above.

[0077] Illustrative examples of metallocenes having a structure represented by Formulas 5, 6A, and 6B may include, but are not limited to any of the following structures, wherein XI and X2 are each independently an optionally substituted Cl -CIO hydrocarbyl; preferably an optionally substituted Cl -CIO alkyl; more preferably an optionally substituted Cl C6 or C6 CIO alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, XI and X2 are each methyl.2025EM046-WG / 050930-0691

[0078] In other examples, suitable Group 4 metal bridged metallocene complexes having Cl symmetry may have a structure represented by Formula 1 and having an optionally substituted aryl group at R3, preferably an optionally substituted phenyl group, an optionally substituted naphthyl group, or an optionally substituted anthracenyl group, which may include variables defined in accordance with the following.

[0079] M is a Group 4 metal; preferably, zirconium or hafnium, more preferably zirconium;

[0080] T is a bridging group; preferably, CRnR12or SiRnR12, wherein R11and R12are independently hydrogen, an optionally substituted C1-C40 hydrocarbyl, or optionally substituted Ce-C62 aryl, or R11and R12are joined to form an optionally substituted C4-C62 saturated or2025EM046-WG / 050930-0691unsaturated cyclic or polycyclic ring structure; more preferably T is CH2, CH2CH2, C(CH3)2, (Ph)2C, (p-(Et)3SiPh)2C, SiMe2, SiPh2, SiMePh, Si(CH2)3, Si(CH2)4, or Si(CH2)4; still more preferably T is CH2 or SiMe2 and more preferably, T is SiMe2 or SiPh2;

[0081] X1and X2are each independently an optionally substituted C1-C10 hydrocarbyl; preferably an optionally substituted C1-C10 alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl;

[0082] R1is hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2 aryl, an optionally substituted C4-Ce2 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10 aryl; preferably, R1is C1-C10 alkyl; more preferably, R1is methyl;

[0083] R2and R6are independently hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2 aryl, an optionally substituted C4-Ce2 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; preferably R2is hydrogen; preferably R2and R6are each hydrogen, or R2is hydrogen and R6is hydrogen or optionally substituted phenyl;

[0084] R3is optionally substituted phenyl, optionally substituted naphthyl, or optionally substituted anthracenyl;

[0085] R4and R5are independently H, R'", or OR'", wherein R'" is an optionally substituted Ci-C4o alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof; and

[0086] R7, R8, R9, and R10are independently hydrogen, a halogen, an optionally substituted Ci-C4o hydrocarbyl, an optionally substituted C4-Ce2 aryl, an optionally substituted C4-Ce2 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R? and R6, R6and R7, or R7and R8are joined to form an optionally substituted C4-C62 saturated or unsaturated cyclic or polycyclic ring structure, or a combination thereof; preferably R3, R6, R7, and R8are each C1-C10 alkyl; more preferably R5, R6, R7, and R8are each methyl.

[0087] Accordingly, in some embodiments, suitable metallocenes having Cl symmetry and an optionally substituted phenyl group at R3may have a structure represented by Formula 72025EM046-WG / 050930-0691R9_ R8R-°< QVR7Formula 7wherein:

[0088] R13-R17are independently hydrogen, an optionally substituted C1-C40 hydrocarbyl, an optionally substituted C4-C62 aryl, an optionally substituted C4-C62 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and each R' is hydrogen, halogen, C1-C10 alkyl, or C6-C10aryl, or R13and R14, R14and R15, R15and R16, or R16and R17, or any combination thereof are joined to form an optionally substituted, saturated, partially unsaturated or aromatic, cyclic or polycyclic ring structure;

[0089] M is a Group 4 metal, preferably Zr or Hf;

[0090] X1and X2are each independently an optionally substituted C1-C10 hydrocarbyl; preferably an optionally substituted C1-C10 alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl;

[0091] R1is C1-C10 alkyl group, preferably methyl;

[0092] R4and R5are independently H, R'", or OR'", wherein R'" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof;

[0093] R6is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14aryl, optionally substituted C3-C13 heteroaryl, -NR'2, -SR', -OR', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene and each R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; preferably R6is hydrogen or optionally substituted phenyl;

[0094] R7, R8, R9, and R10are independently hydrogen, a halogen, an optionally substituted C1-C40 hydrocarbyl, an optionally substituted C4-C62 aryl, an optionally substituted C4-C62 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkylene2025EM046-WG / 050930-0691and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R3and R6, R6and R7, or R7and R8are joined to form an optionally substituted C4-C62 saturated or unsaturated cyclic or polycyclic ring structure, or a combination thereof; preferably R3, R6, R7, and R8are each C1-C10 alkyl; more preferably R5, R6, R7, and R8are each methyl; and

[0095] R11and R12are independently optionally substituted C1-C10 alkyl, or optionally substituted C6-C10aryl, or R11and R12are joined to form an optionally substituted C2-C22 saturated or unsaturated cyclic or polycyclic ring structure; more preferably R11and R12are each methyl or phenyl, and more preferably, R11and R12are each methyl.

[0096] In some examples, R4and R5may form a 5-membered carbocyclic ring. Specific examples of such metallocenes having an optionally substituted phenyl group at R3and having R4and R5fused as a 5-membered carbocyclic ring may have a structure represented by Formula 8A, preferably wherein R6is hydrogen or optionally substituted phenyl, and more preferably wherein R6is hydrogen. The metallocene represented by Formula 8B lacks the 5-membered carbocyclic ring fused to the indenyl group.Formula 8A Formula 8B wherein in Formula 8A:

[0097] Q is an optional Ci-Ce alkyl group, and q is 0, 1, 2, 3, 4, 5, or 6. When present (q 0), optional substitution Q may be present at any non-aromatic carbon atom of the 5-membered ring defined by R4and R3. Preferably, each occurrence of Q is a methyl group. The other variables are defined as above.

[0098] Illustrative examples of metallocenes having a structure represented by Formulas 7, 8A, or 8B may include, but are not limited to, any of the following structures, X1and X2are each independently an optionally substituted C1-C10 hydrocarbyl; preferably an optionally substituted C1-C10 alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferablymethyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl.2025EM046-WG / 050930-06912025EM046-WO / 050930-06912025EM046-WG / 050930-06912025EM046-WG / 050930-06912025EM046-WG / 050930-06912025EM046-WG / 050930-0691where Hf may replace Zr in any of the foregoing metallocenes.

[0099] In more specific examples, the variables in Formula 1 may be defined as follows.

[0100] M is the Group 4 metal, preferably Zr or Hf;

[0101] T is a bridging group, preferably Si(CH3)2;

[0102] X1and X2are each independently an optionally substituted Ci-Cio hydrocarbyl; preferably an optionally substituted Ci-Cio alkyl; more preferably an optionally substituted Ci-Ce or Ce-Cio alkyl; more preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, or benzyl; more preferably, X1and X2are each methyl;

[0103] R1is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR', -O R', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or Cg-Cio aryl;

[0104] R3is optionally substituted C1-C40 alkyl or optionally substituted C6-C14 aryl;

[0105] R4and R3are independently H, R'", or OR'", wherein R'" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof;

[0106] R6is independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; and

[0107] R7, R8, R9, and R10are independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR1, -OR’,-SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or Cg-Cio aryl, or one or more of R7and R8, R8and R9, or R9and R10are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof.

[0108] Illustrative examples of suitable metallocene complexes may include, but are not limited to, any of the following structures:2025EM046-WG / 050930-0691

[0109] Methods of the present disclosure for forming the metallocene complexes may comprise: contacting a Group 4 tetrahalide and a metal hydrocarbyl reagent in an ether solvent, thereby forming a first reaction product in a first mixture; and, without isolating the first reaction product from the first mixture, combining the first mixture with a dilithium salt of a bridged bis(cyclopentadienyl) compound, thereby forming a second reaction product in a second mixture, the second reaction product comprising a Group 4 metal bridged metallocene complex having two hydrocarbyl leaving groups.

[0110] In forming the first mixture, the Group 4 metal tetrahalide, the metal hydrocarbyl reagent, and the ether solvent may be contacted in any order. For example, the Group 4 metal tetrahalide and the metal hydrocarbyl reagent may be sequentially added to the ether solvent in either order. Optionally, the Group 4 metal tetrahalide and the metal hydrocarbyl reagent may be added to a first portion of the ether solvent, followed by adding a second portion of the ether solvent to form thereby form the first mixture. Optionally, the Group 4 metal tetrahalide and / or the metal hydrocarbyl reagent may be dissolved in the ether solvent when being combined to form the first mixture. Upon contacting the Group 4 metal tetrahalide and the metal hydrocarbyl reagent in the ether solvent, a first reaction product may be formed in the first mixture. Without being bound by any theory or mechanism, two hydrocarbyl groups may displace two halide groups from the Group 4 metal tetrahalide to form a reaction product comprising a Group 4 metal complex having two halide ligands and two hydrocarbyl ligands. Optionally, one or more ether ligands from the ether solvent may complex the Group 4 metal in the resulting Group 4 metal complex.

[0111] Contacting the Group 4 metal tetrahalide and the metal hydrocarbyl reagent in the ether solvent may occur for a sufficient period of time to form the first reaction product in the first mixture. For example, the period of time sufficient to form the first reaction product may range from about al to about a2, where al and a2 may be, independently, 0.1 hour, 0.5 hour, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, or 12 hours, where al< a2. In non-limiting examples, the period of time to form the first reaction product may range from about 0.1 hour to about 6 hours, or about 0.5 hour to about 4 hours, or about 0.5 hour to about 3 hours, or about 0.5 hour to about 2 hours, or about 0.5 hour to about 1 hour.

[0112] During at least a portion of the period of time while forming the first reaction product, the first mixture may be maintained at a temperature of about b 1 to about b2, where b 1 and b2 may be, independently, -30°C, -29°C, -28°C, -27°C, -26°C, -25°C, -24°C, -23°C, -22°C, -21°C, -20°C,2025EM046-WG / 050930-0691-19°C, -18°C, -17°C, -16°C, -15°C, -14°C, -13°C, -12°C, -11°C, -10°C, -9°C, -8°C, -7°C, -6°C, -5°C, -4°C, -3°C, -2°C, -1°C, or 0°C, where bl< b2. In non-limiting examples, the first mixture may be maintained at a temperature of about -30°C to about 0°C, or about -25°C to about 0°C, or about -20°C to about 0°C, or about -15°C to about 0°C, or about -10°C to about 0°C, or about -5°C to about 0°C. For example, the metal hydrocarbyl reagent may be added to a precooled mixture of the Group 4 metal tetrahalide and the ether solvent, wherein the pre-cooled mixture is maintained within the foregoing ranges.

[0113] Suitable Group 4 metal tetrahalides may include tetrachlorides, tetrabromides, tetraiodides, tetrafluorides, the like, or any combination thereof. The Group 4 metal of the Group 4 metal tetrahalides may comprise any of Ti, Zr, or Hf. Therefore, in some examples, suitable Group 4 metal tetrahalides may include titanium tetrachloride (TiCh), titanium tetrabromide (TiBr4), zirconium tetrachloride (ZrCE), zirconium tetrabromide (ZrBr4), hafnium tetrachloride (HfCl4), hafnium tetrabromide (HfBr4), the like, and any combination thereof. ZrCl4 and HfCl4 may be preferred Group 4 metal tetrahalides.

[0114] Suitable metal hydrocarbyl reagents may include, for example, organolithium compounds and organomagnesium compounds. Such metal hydrocarbyl reagents may comprise a lithium or magnesium atom bonded to one or more hydrocarbyl groups. When multiple hydrocarbyl groups are present in the metal hydrocarbyl reagents (e.g., in organomagnesium compounds), the hydrocarbyl groups may be the same or different. Suitable hydrocarbyl groups may include any Ci-Cioo hydrocarbyl groups, which may be linear, branched, or cyclic, and, when cyclic, aromatic or non-aromatic in nature. Suitable hydrocarbyl groups may be substituted or unsubstituted. In some examples, the hydrocarbyl groups may comprise Ci-Cio optionally substituted hydrocarbyl groups, such as methyl groups, benzyl groups, phenyl groups, and the like, preferably methyl groups.

[0115] Suitable organolithium reagents may include, for example, methyl lithium, benzyl lithium, or the like. Suitable organomagnesium reagents may include methyl magnesium bromide, methyl magnesium chloride, benzyl magnesium bromide, benzyl magnesium chloride, and the like.

[0116] Ether solvents suitable for use in methods of the present disclosure may include, for example, dimethoxy ethane (glyme), diglyme, triglyme, tetraglyme, diethyl ether, 1,4-di oxane, methyl tert-butyl ether, tetrahydrofuran, or any combination thereof. Ether solvents may be2025EM046-WG / 050930-0691particularly suitable due to their limited reactivity with the metal hydrocarbyl reagent, as well as their ability to complex the Group 4 metal of the first reaction product. In the case of diether solvents, such as dimethoxyethane, the ether solvent may chelate the Group 4 metal center.

[0117] Without isolating the first reaction product from the first mixture, a dilithium salt of a bridged bis(cyclopentadienyl) compound may be combined with the first mixture to form a second reaction product in a second mixture. The first mixture may be combined with a solution of the dilithium salt or vice versa. The second reaction product may comprise a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups. Illustrative Group 4 metal bridged bis(metallocene) complexes having two hydrocarbyl leaving groups include those described above in reference to Formulas 1-8.

[0118] Methods of the present disclosure may further comprise isolating the second reaction product. In non-limiting examples, isolation may be conducted by filtration, decantation, centrifugation, settling, or any combination thereof.

[0119] The dilithium salt of the bridged bis(cyclopentadienyl) compound may be pre-formed prior to being combined with the first mixture. For example, the dilithium salt may be formed by reacting an organolithium reagent with a bridged bis(cyclopentadiene) compound. The dilithium salt may be present in an ether solvent when being combined with the first mixture, or the dilithium salt may be added as a free solid.

[0120] Combining the first mixture with the dilithium salt of the bridged bis(cyclopentadienyl) compound may be conducted over a time period to maintain a desired rate of reaction. For example, the first mixture and the dilithium salt may be combined at a rate sufficient to maintain a desired temperature, such as to avoid an undesired exotherm.

[0121] In forming the second reaction product, the first reaction product and the dilithium salt of the bridged bis(cyclopentadienyl) compound may be contacted with each other for a sufficient period of time for the second reaction product to form. The sufficient period of time to form the second reaction product may range from about cl to about c2, where cl and c2 may be, independently, 0.5 hour, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, 30 hours, 31 hours, 32 hours, 33 hours, 34 hours, 35 hours, 36 hours, 37 hours, 38 hours, 39 hours, 40 hours, 41 hours, 42 hours, 43 hours, 44 hours, 45 hours, 46 hours, 47 hours or 482025EM046-WG / 050930-0691hours, where cl< c2. In non-limiting examples, the sufficient period of time may range from about 0.5 hour to about 48 hours, or about 0.5 hour to about 36 hours, or about 0.5 hour to about 24 hours, or about 0.5 hour to about 10 hours, or about 0.5 hour to about 6 hours, or about 0.5 hour to about 1 hour.

[0122] During at least a portion of the period of time while forming the second reaction product, the second mixture may be maintained at a temperature of about dl to about d2, where dl and d2 may be, independently, -30°C, -29°C, -28°C, -27°C, -26°C, -25°C, -24°C, -23°C, -22°C, -21°C, -20°C,-19°C, -18°C, -17°C, -16°C, -15°C, -14°C, -13°C, -12°C, -11°C, -10°C, -9°C, -8°C, -7°C, -6°C, -5°C, -4°C, -3°C, -2°C -1°C, or 0°C, where dl< d2. In non-limiting examples, the second mixture may be maintained at a temperature of about -30°C to about 0°C, or about -25°C to about 0°C, or about -20°C to about 0°C, or about -15°C to about 0°C, or about -10°C to about 0°C, or about -5°C to about 0°C.

[0123] After the second mixture has been maintained within the range of about dl to about d2 for a desired length of time, as described above, the second mixture may be warmed to and maintained at room temperature, such as over about 1 hour to about 6 hours, or about 6 hours to about 12 hours, or about 12 hours to about 24 hours, or for about 16 hours to 20 hours, or for about 18 hours.

[0124] In certain embodiments, the dilithium salt of the bridged bis(cyclopentadienyl) compound may be present in the first mixture prior to forming the first reaction product, such that the second mixture forms automatically as the first reaction product forms within the first mixture.Catalyst Systems

[0125] Once the second reaction product has been formed in accordance with the description above, the second reaction product (i.e., the Group 4 metal bridged metallocene complex having two hydrocarbyl leaving groups) may be combined with an activator, optionally a co-activator, and optionally, a support material to form a catalyst system. Additional description of suitable activators, co-activators, support materials, and the resulting catalyst systems is provided hereinafter. Catalyst systems comprise at least one activator in combination with the Group 4 metal bridged metallocene complexes having two hydrocarbyl leaving groups. Suitable activators may include alumoxanes (e.g., MAO), non-coordinating anion activators, or any combination thereof.2025EM046-WG / 050930-0691

[0126] Alumoxanes are generally oligomeric compounds containing -A1(R)-O- sub-units, where R is an alkyl group. Examples of alumoxanes include (MAO), modified MAO (MMAO), ethylalumoxane, isobutylalumoxane, and the like. Mixtures of different alumoxanes and modified alumoxanes may be used, if desired. It may be preferable to use a visually clear MAO when forming a catalyst system. A cloudy or gelled alumoxane can be filtered to produce a clear solution or clear alumoxane can be decanted from the cloudy solution. A useful alumoxane is a modified MAO (MMAO) cocatalyst type 3 A (commercially available from Akzo Chemicals, Inc. under the trade name Modified Methylalumoxane type 3A and described in U. S. Patent No. 5,041,584). Another useful alumoxane is solid polymethylaluminoxane as described in US Patents 9,340,630; 8,404,880; and 8,975,209.

[0127] When the activator is an alumoxane (modified or unmodified), a maximum amount of activator may be selected at up to a 5000-fold molar excess Al / M over the complex (per metal catalytic site of the metallocene). The minimum activator-to-metal ratio is a 1:1 molar ratio. Suitable ranges may include from 1: 1 to 500: 1, or from 1: 1 to 200: 1, or from 1: 1 to 150: 1, or from 1:1 to 100:1, or from 1:1 to 50:1.

[0128] Other suitable activators include compounds containing a non-coordinating anion, especially borane and borate compounds. Particularly useful borane and borate compounds containing a non-coordinating anion or similar entity include, for example, B(C6F5)3, [PhNMe2H]+[B(C6F5)4]-, [Ph3C]+[B(C6F5)4]’, and [PhNMe2H]+[B(CioF7)4]’.

[0129] The term “non-coordinating anion” (NCA) means an anion which either does not coordinate to a cation or which is only weakly coordinated to a cation thereby remaining sufficiently labile to be displaced by a neutral Lewis base. The term NCA is defined to include multicomponent NCA-containing activators, such as N, N-dimethylanilinium tetrakis(pentafluorophenyl)borate and N, N-dimethylanilinium tetrakis(heptafluoronaphthyl)borate, that contain an acidic cationic group and the non-coordinating anion. The term NCA is also defined to include neutral Lewis acids, such as tris(pentafluorophenyl)boron, that can react with a metallocene complex to form an activated species by abstraction of an anionic group. Typically, NCAs coordinate weakly enough that a neutral Lewis base, such as an olefinically or acetylenically unsaturated monomer can displace it from the metal center. Any metal or metalloid that can form a compatible, weakly coordinating complex may be used or contained in the non-coordinating anion. Suitable metals include, but are2025EM046-WG / 050930-0691not limited to, aluminum, gold, and platinum. Suitable metalloids include, but are not limited to, boron, aluminum, phosphorus, and silicon. The term non-coordinating anion includes neutral activators, ionic activators, and Lewis acid activators.

[0130] “Compatible” non-coordinating anions are those which are not degraded to neutrality when the initially formed complex decomposes. Further, the anion will not transfer an anionic substituent or fragment to the cation so as to cause it to form a neutral transition metal complex and a neutral by-product from the anion. Non-coordinating anions useful in accordance with the present disclosure are those that are compatible, stabilize the transition metal cation in the sense of balancing its ionic charge at +1, and yet retain sufficient lability to permit displacement during polymerization. Ionizing activators useful herein typically comprise an NCA, particularly a compatible NCA.

[0131] It is within the scope of the present disclosure to use an ionizing, neutral, or ionic activator, such as tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate, a tris perfluorophenylboron metalloid precursor or a trisperfluoronaphthylboron metalloid precursor, polyhalogenated heteroborane anions (WO 98 / 43983), boric acid (U. S. Patent No. 5,942,459), or any combination thereof. It is also within the scope of the present disclosure to use neutral or ionic activators alone or in combination with alumoxane or modified alumoxane activators. Other useful activators may include those described in US Patents 8,658,556 and 6,211,105.

[0132] In preferred embodiments, boron-containing NCA activators represented by Formula 10 below may be used,Zd+(Ad’)Formula 10where Z is (L-H) or a reducible Lewis acid; L is a neutral Lewis base; H is hydrogen; (L-H)is a Bronsted acid; Ad' is a boron-containing non-coordinating anion having the charge d'; and d is 1, 2, or 3.

[0133] The cation component Zd+may include Bronsted acids such as protons or protonated Lewis bases or reducible Lewis acids capable of protonating or abstracting a moiety from the metal-ligand complexes to afford a cationic metal-ligand complex.

[0134] The cation component Zd+may also be a moiety such as silver, tropylium, carboniums, ferroceniums and mixtures thereof, preferably carboniums and ferroceniums. Suitable reducible Lewis acids include any triaryl carbonium (where the aryl can be optionally substituted, such as2025EM046-WG / 050930-0691those represented by the formula: (Ar3C+), where Ar is aryl or aryl substituted with a heteroatom, a Ci to C40 hydrocarbyl, or a substituted Ci to C40 hydrocarbyl). Preferably, the reducible Lewis acids in Formula 9 above defined as " Z" include those represented by the formula: (Ph3C+), where Ph is an optionally substituted phenyl, preferably substituted with Ci to C40 hydrocarbyls or substituted Ci to C40 hydrocarbyls, preferably Ci to C20 alkyls or aromatics or substituted Ci to C20 alkyls or aromatics, and preferably Z+is triphenylcarbonium.

[0135] When Z+is the activating cation (L-H)+, it is preferably a Bronsted acid, capable of donating a proton to the transition metal catalytic precursor, resulting in a transition metal cation, including ammoniums, oxoniums, phosphoniums, silyliums, and mixtures thereof, preferably ammoniums of methylamine, aniline, dimethylamine, diethylamine, N-methylaniline, diphenylamine, trimethylamine, triethylamine, N, N-dimethylaniline, methyldiphenylamine, pyridine, p-bromo-N, N-dimethylaniline, p-nitro-N, N-dimethylaniline, phosphoniums from triethylphosphine, triphenylphosphine, and diphenylphosphine, oxoniums from ethers such as dimethyl ether, diethyl ether, tetrahydrofuran and dioxane, sulfoniums from thioethers, such as diethyl thioethers, tetrahydrothiophene, and mixtures thereof.

[0136] The anion component Ad’ includes those having the formula [Mk+G]d‘ wherein k is 1, 2, or 3; G is 1, 2, 3, 4, 5, or 6 (preferably 1, 2, 3, or 4); G - k = d; M is an element selected from Group 13 of the Periodic Table of the Elements, preferably boron or aluminum, and G is independently a hydride, bridged or unbridged dialkylamido, halide, alkoxide, aryloxide, hydrocarbyl, substituted hydrocarbyl, halocarbyl, substituted halocarbyl, and halo-substituted hydrocarbyl radicals, said G having up to 20 carbon atoms with the proviso that in not more than 1 occurrence is G a halide. Preferably, each G is a fluorinated hydrocarbyl group having 1 to 20 carbon atoms, more preferably, each G is a fluorinated aryl group, and most preferably, each G is a pentafluoroaryl group. Examples of suitable Ad' also include diboron compounds as disclosed in U. S. Patent No. 5,447,895, which is fully incorporated herein by reference with respect to the diboron compounds disclosed therein.

[0137] Illustrative but not limiting examples of boron compounds which may be used as an activator are the compounds described as (and particularly those specifically listed as) activators in U. S. Patent 8,658,556, which is incorporated by reference herein with respect to the boron compounds disclosed therein.2025EM046-WG / 050930-0691

[0138] Most preferably, the activator Za+(Ad‘) is one or more of N, N-dimethylanilinium tetra(perfluorophenyl)borate, N, N-dimethylanilinium tetrakis(perfluoronaphthyl)borate, N, N-dimethylanilinium tetrakis(perfluorobiphenyl)borate, N, N-dimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbenium tetrakis(perfluoronaphthyl)borate, triphenylcarbenium tetrakis(perfluorobiphenyl)borate, triphenylcarbenium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, or triphenylcarbenium tetra(perfluorophenyl)borate. In any embodiment, the non-coordinating anion may be selected from N, N-dimethylanilinium tetrakis(perfluoronaphthyl)borate, N, N-dimethylanilinium tetrakis(perfluorobiphenyl)borate, N, N-dimethylanilinium tetrakis(perfluorophenyl)borate, N, N-dimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbenium tetrakis(perfluoronaphthyl)borate, triphenylcarbenium tetrakis(perfluorobiphenyl)borate, triphenylcarbenium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbenium tetrakis(perfluorophenyl)borate, [Me4NH+][B(C6F5)4]-, l-(4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluorophenyl) pyrrolidinium;[Me4NH+][B(C6F5)4]-, l-(4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluorophenyl) pyrrolidinium, sodium tetrakis(pentafluorophenyl)borate, potassium tetrakis(pentafluorophenyl)borate, and 4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluoropyridinium. Preferably, the non-coordinating anion may be N, N-dimethylanilinium tetrakis(perfluoronaphthyl)borate.

[0139] Bulky activators are also useful herein as NCAs. " Bulky activator" as used herein refers to anionic activators represented by Formulas 11 or 12 below.Formula 11 Formula 12In Formulas 11 and 12, each Rlais, independently, a halide, preferably a fluoride; Ar is an optionally substituted aryl group (preferably an optionally substituted phenyl), preferably substituted with C1 to C40hydrocarbyls, preferablyto C20alkyls or aromatics; each R2ais, independently, a halide, a C6to C20substituted aromatic hydrocarbyl group or a siloxy group of2025EM046-WG / 050930-0691the formula -O-Si-Ra, where Rais a C1to C20hydrocarbyl or hydrocarbyl silyl group (preferably R2ais a fluoride or a perfluorinated phenyl group); each R3ais a halide, C6to C20substituted aromatic hydrocarbyl group or a siloxy group of the formula -O-Si-Ra, where Rais a C, to C20hydrocarbyl or hydrocarbylsilyl group (preferably R3ais a fluoride or a C6perfluorinated aromatic hydrocarbyl group); wherein R2aand R3acan form one or more saturated or unsaturated, optionally substituted rings (preferably R2aand R3aform a perfluorinated phenyl ring); and L is a neutral Lewis base; (L-H) is a Bronsted acid; d is 1, 2, or 3; wherein the anion has a molecular weight of greater than 1020 g / mol; wherein at least three of the substituents on the B atom each have a molecular volume of greater than 250 cubic A, greater than 300 cubic A, or greater than 500 cubic A, as specified below.

[0140] Preferably, (Ad-) is (Ph3C)+, where Ph is an optionally substituted phenyl, preferably substituted with Ci to C40 hydrocarbyls or substituted Ci to C40 hydrocarbyls, preferably Ci to C20 alkyls or aromatics or substituted Ci to C20 alkyls or aromatics.

[0141] " Molecular volume" is used herein as an approximation of spatial steric bulk of an activator molecule in solution. Comparison of substituents with differing molecular volumes allows the substituent with the smaller molecular volume to be considered "less bulky" in comparison to the substituent with the larger molecular volume. Conversely, a substituent with a larger molecular volume may be considered "more bulky" than a substituent with a smaller molecular volume. Molecular volume may be calculated as reported in " A Simple ‘Back of the Envelope’ Method for Estimating the Densities and Molecular Volumes of Liquids and Solids," Journal of Chemical Education, Vol. 71, No. 11, November 1994, pp. 962-964. Molecular volume (MV), in units of cubic A, is calculated using the formula: MV = 8.3Vs, where Vsis the scaled volume. Vsis the sum of the relative volumes of the constituent atoms, and is calculated from the molecular formula of the substituent as specified below. For fused rings, the Vsis decreased by 7.5% per fused ring. The Calculated Total MV of the anion is the sum of the MV per substituent, for example, the MV of perfluorophenyl is 183 A3, and the Calculated Total MV for tetrakis(perfluorophenyl)borate is four times 183 A3, or 732 A3.Element Relative VolumeH 12025EM046-WG / 050930-06911stshort period, Li to F 22ndshort period, Na to Cl 41stlong period, K to Br 52ndlong period, Rb to I 7.53rdlong period, Cs to Bi 9For a list of particularly useful bulky activators, U. S. Patent 8,658,556, which is incorporated by reference herein with respect to its disclosure of bulk activators, may be consulted.

[0142] In any embodiment, an NCA activator may be an activator as described in U. S. Patent No. 6,211,105. The NCA activator-to-complex ratio may be from about a 1:1 molar ratio to about a 1000:1 molar ratio, which includes from about 0.1:1 to about 100:1, from about 0.5:1 to about 200:1, from about 1:1 to about 500:1, or from about 1:1 to about 1000:1. A particularly useful range is from about 0.5:1 to about 10:1, preferably about 1:1 to about 5:1.

[0143] It is also within the scope of this disclosure that the metallocenes may be activated with combinations of alumoxanes and NCAs (see for example, U. S. Patents 5,153,157 and 5,453,410; EP 0 573 120 Bl, and International Patent Application Publications WO 94 / 07928 and WO 95 / 14044, which discuss the use of an alumoxane in combination with an ionizing activator). Thus, in some embodiments, an NCA may be a co-activator to an alumoxane, or vice versa.

[0144] In addition to activators, scavengers or co-activators may also be present. Aluminum alkyl or organoaluminum compounds which may be utilized as scavengers or co-activators include, for example, trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, ethylaluminum dichloride, di ethylaluminum chloride, and diethyl zinc.

[0145] Chain transfer agents can also be used in the compositions and / or processes described herein. Useful chain transfer agents are typically alkylalumoxanes, a compound represented by the formula AIR3, ZnR2(where each R is, independently, a C1-C8aliphatic radical, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl or an isomer thereof) or a combination thereof, such as diethyl zinc, MAO, trimethylaluminum, triisobutylaluminum, trioctylaluminum, or a combination thereof.

[0146] In any embodiment, an alumoxane, such as MAO, may be mixed in an inert solvent, such as toluene, and then be slurried with a support material, such as silica. Alumoxane deposition upon2025EM046-WG / 050930-0691the support material may occur at a temperature from about -20°C to about 0°C, or about 0°C to about 30°C, or about -20°C to about 20°C, or at approximately room temperature. After deposition of the alumoxane or other activator upon the support material, the resulting supported activator may be optionally aged. If performed, aging may be conducted over about 0.5 hr to about 24 hours, or 1 hour to about 12 hours, and at a temperature of about 60°C to about 110°C, or about 70°C to about 100°C, or about 80°C about 110°C.

[0147] Any of the Group 4 bridged metallocene compounds provided herein may be supported or unsupported. Optionally, methods for preparing metallocene catalyst systems according to the present disclosure may include disposing the Group 4 metal bridged metallocene complex upon a support material. When a support material is used, at least one activator may also be disposed upon the support material in combination with the Group 4 metal bridged metallocene complex, optionally in further combination with a co-activator and / or a scavenger. Suitable activators and co-activators are described above. The activator or co-activator may be disposed upon the support material by contacting the support material with a solution containing the activator or the activator, or the activator may be formed in situ upon the support material.

[0148] The support material may be an inorganic oxide in a finely divided form, such as silica, alumina, talc, zeolites, clays, organoclays, and the like, each having a highly porous structure. Suitable inorganic oxides include Groups 2, 4, 13, or 14 metal oxides, such as silica, alumina, and mixtures thereof. Other inorganic oxides may be employed, either alone or in combination with the silica or alumina, such as magnesia, titania, zirconia, or the like. Particularly useful support materials may include magnesia, titania, zirconia, montmorillonite, phyllosilicate, zeolites, talc, silica, clays, silica clay, silicon oxide clay, and the like. Combinations of these support materials may be used such as, for example, silica-chromium, silica-alumina, silica-titania, and the like. In at least one embodiment, the support material may be selected from Al2O3, ZrO2, SiO2, SiO2 / Al2O3, silica clay, silicon oxide / clay, or mixtures thereof. Other suitable support materials may be employed as well such as, for example, finely divided functionalized polyolefins, such as finely divided polyethylene, polypropylene, and polystyrene with functional groups that are able to absorb water, (e.g., oxygen- or nitrogen-containing groups such as -OH, -RC=O, -OR, and -NR2). Still other organic or inorganic support materials may also be suitably used.

[0149] The support material may be optionally treated with an electron-withdrawing anion. The electron-withdrawing anion may increase the Lewis or Bronsted acidity of the support material, as2025EM046-WG / 050930-0691compared to the support material that is not treated. The electron-withdrawing anion may be derived from a salt, an acid, or other compounds, such as a volatile organic compound, that serve as a source or precursor for the electron-withdrawing anion. Electron-withdrawing anions may include sulfate, bisulfate, fluoride, chloride, bromide, iodide, fluorosulfate, fluoroborate, phosphate, fluorophosphate, trifluoroacetate, triflate (trifluoromethanesulfonate), fluorozirconate, fluorotitanate, phosphotungstate, or any combination thereof. Combinations of one or more different electron-withdrawing anions, in varying proportions, may be used to tailor the specific acidity of the support material to a desired level. Such combinations of electron- withdrawing anions may be contacted with the support material simultaneously or individually and in any order that provides a desired specific acidity.

[0150] The support material may be optionally fluorided by introducing a fluoride-containing anion. For example, a fluorided support may be a silicon dioxide support wherein a portion of the silica hydroxyl groups have been replaced with fluorine or a fluorine-containing compound. Suitable fluorine-containing compounds include, but are not limited to, inorganic fluorine-containing compounds and / or organic fluorine-containing compounds, either of which may be utilized for providing fluorine to the support material. Illustrative inorganic fluorine-containing compounds that may be used for fluoriding a support material include, for example, NH4BF4, (NH4)2SiF6, NH4PF6, NH4F, (NH4)2TaF7, NH4NbF4, (NH4)2GeF6, (NH4)2SmF6, (NH4)2TiF6, (NH4)2ZrF6, MoF6, ReF6, GaF3, SO2ClF, F2, SiF4, SF6, ClF3, ClF5, BrF5, IF7, NF3, HF, BF3, NHF2, NH4HF2, and combinations thereof.

[0151] Non-limiting examples of cations suitable for use in the present disclosure in combination with the electron-withdrawing anion include ammonium, trialkylammonium, tetraalkylammonium, tetraalkylphosphonium, H+, [H(OEt2)2]+, [HNR3]+(R is a C1-C20hydrocarbyl group, which may be the same or different and optionally substituted), or combinations thereof.

[0152] The method by which the support material is contacted with the electron-withdrawing anion, may include, but is not limited to, gelling, co-gelling, impregnation of one compound onto another, the like, or combinations thereof. Following a particular contacting method, the treated support material may then be calcined.

[0153] The support material, such as an inorganic oxide and more preferably silica, may have a surface area about 10 m2 / g to about 800 m2 / g, or about 10 m2 / g to about 500 m2 / g, or about 10 m2 / g to about 100 m2 / g, or about 10 m2 / g to about 50 m2 / g, or about 50 m2 / g to about 800 m2 / g, or2025EM046-WG / 050930-0691about 50 m2 / g to about 500 m2 / g, or about 50 m2 / g to about 100 m2 / g, or about 100 m2 / g to about 800 m2 / g, or about 100 m2 / g to about 500 m2 / g, or about 500 m2 / g to about 800 m2 / g.

[0154] The support material, such as an inorganic oxide and more preferably silica, may have a pore volume of about 0.1 cc / g to about 4.0 cc / g, or about 0.1 cc / g to about 1 cc / g, or about 1 cc / g to about 4 cc / g. The average pore size of the support material may be about 10 A to about 1000 A, or about 10 A to about 500 A, or about 10 A to about 100 A, or about 100 A to about 1000 A, or about 100 A to about 500 A, or about 500 A to about 1000 A.

[0155] The support material, such as an inorganic oxide and more preferably silica, may have an average particle size of about 5 pm to about 500 pm, or about 5 pm to about 100 pm, or about 5 pm to about 50 pm, or about 50 pm to about 500 pm, or about 50 pm to about 100 pm, or about 100 pm to about 500 pm.

[0156] Before employing the support material in a polymerization reaction or before disposing a metallocene thereon, the support material may be free or substantially free of absorbed water. Drying of the support material can be realized by heating or calcining at about 100°C to about 1000°C, preferably at least about 200°C. When the support material is silica, the silica may be heated to at least about 200°C, preferably about 200°C to about 850°C, and more preferably at about 400°C; and for a time of about 1 minute to about 100 hours, or from about 12 hours to about 72 hours, or from about 24 hours to about 60 hours. After calcination, the support material may be contacted with a metallocene and optionally an activator to produce a metallocene catalyst system.

[0157] To accomplish the foregoing, the support material may be slurried in a non-polar solvent and contacted with a solution of the metallocene and an activator. Optionally, the activator may be deposited upon the support material before contacting the metallocene with the support material. Further optionally, the supported activator may be aged before contacting the metallocene, as discussed above. The slurry of the support material may first be contacted with the activator for about 0.5 hours to about 24 hours, or about 2 hours to about 16 hours, or about 4 hours to about 8 hours before disposing the metallocene thereon. Alternately, the slurry of the support material may first be contacted with the metallocene for about 0.5 hours to about 24 hours, or about 2 hours to about 16 hours, or about 4 hours to about 8 hours before being contacted with an activator.

[0158] Once the metallocene and the activator have been contacted with each other and deposited upon the support material, the resulting metallocene catalyst system may be aged, optionally with heating at a temperature ranging from about 60°C to about 110°C, or about 70°C to about 100°C,2025EM046-WG / 050930-0691or about 80°C to about 110°C and for a time ranging from about 0.5 hours to about 24 hours, or about 2 hours to about 16 hours, or about 4 hours to about 8 hours, or about 1 hour to about 4 hours before being used to conduct a polymerization reaction.

[0159] Suitable non-polar solvents for loading the metallocene compound and the activator upon the support material may include those in which the metallocene and the activator are at least partially soluble and which are liquids at reaction temperatures. Preferred non-polar solvents are alkanes, such as isopentane, hexane, n-heptane, octane, nonane, or decane, although a variety of other materials including cycloalkanes, such as cyclohexane. Aromatic hydrocarbons, such as benzene, toluene, and ethylbenzene, may also be employed.

[0160] In view of the foregoing, the present disclosure further provides metallocene catalyst systems comprising a support material; a Group 4 bridged metallocene complex containing two hydrocarbyl leaving groups disposed upon the support material; and optionally, an activator selected from an alumoxane or NCA also disposed upon the support material. The Group 4 bridged metallocene complex and the activator may be disposed upon the support material in any order, including concurrently. Suitable ratios of the activator to the Group 4 metal may include the A1: M ratios specified above.Polymerization Methods

[0161] The Group 4 metal bridged bis(metallocene) complex and metallocene catalyst systems thereof may be used to polymerize alpha olefins into polyolefin polymers, copolymers, oligomers, or the like. Polymerization methods for producing polyolefins according to the present disclosure may comprise exposing an alpha olefin to a Group 4 metal bridged bis(metallocene) complex of the present disclosure at a sufficient temperature to start the polymerization, such as, for example, a temperature of about 70°C, for a sufficient period of time, such as about 30 minutes to 1 hour. Polymerization reactions may be conducted in the presence or absence of one or more scavengers. The term “scavenger” refers to a compound that may be added to a metallocene catalyst system to facilitate polymerization by scavenging impurities. Some scavengers may also act as activators and may be referred to as co-activators. A co-activator that is not a scavenger may also be used in conjunction with an activator in order to form an active metallocene catalyst system. In at least one embodiment, a co-activator can be pre-mixed with a complex to form an alkylated metal complex. Typical scavengers include trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-octylaluminum, diethyl zinc, or excess alumoxane activator. If desired, hydrogen may be2025EM046-WG / 050930-0691added during either of the polymerization reactions to alter the molecular weight of the polymer being produced. In at least one embodiment, hydrogen may be present in the polymerization reaction at about 0.5 millimol of hydrogen per liter to about 15 millimol of hydrogen per liter.

[0162] Polymerization of polypropylene using a Group 4 metal bridged bis(metallocene) complex by methods of the present disclosure may produce a polypropylene having an Mw value of about 100,000 to about 500,000 and exhibit a wide molecular weight distribution (Mw / Mn). As used herein, Mn is number average molecular weight, Mw is weight average molecular weight, and Mz is z average molecular weight, wt% is weight percent, and mol% is mole percent. Molecular weight distribution (MWD), also referred to as polydispersity index (PDI), is defined to be Mw divided by Mn. Unless otherwise noted, all molecular weight units (e.g., Mw, Mn, and Mz) are in units of g / mol (g’mol1). In non-limiting examples, the MWD of the polypropylene may be about 2 or more, or about 3 or more, or about 4 or more, or about 5 or more, or about 6 or more, or about 7 or more, or about 8 or more, or about 9 or more, or about 10 or more. In certain embodiments, polymerization produces a polypropylene having an Mw value of about 130,000 to about 150,000, and an Mw / Mn value of about 2.4 to about 3.5. In non-limiting examples, the polypropylene produced using the Group 4 metal bridged bis(metallocene) complexes produced according to the disclosure herein may have a melting point ranging from about 140°C to about 170°C, or about 150°C to about 160°C.

[0163] Group 4 metal bridged bis(metallocene) complexes produced as described herein may have increased catalytic activity when polymerizing alpha olefins such as propylene, as compared to their dihalide counterparts.

[0164] In certain embodiments, the catalytic activity for propylene polymerization for Group 4 metal bridged bis(metallocene) complex comprising dimethyl hydrocarbyl leaving groups produced as described herein may be about 50% higher than for the corresponding dichloride counterparts, and about 30% greater than for the corresponding dibenzyl counterparts.Additional Embodiments

[0165] Embodiments disclosed herein include:

[0166] Embodiment 1. A method comprising: contacting a Group 4 metal tetrahalide and a metal hydrocarbyl reagent in an ether solvent, thereby forming a first reaction product in a first mixture; and without isolating the first reaction product, combining the first mixture with a dilithium salt of a bridged bis(cyclopentadienyl) compound, thereby forming a second reaction2025EM046-WG / 050930-0691product in a second mixture, the second reaction product comprising a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups.

[0167] Embodiment 2. The method of Embodiment 1, wherein combining the first mixture with the dilithium salt comprises combining the dilithium salt with the Group 4 metal tetrahalide and the metal hydrocarbyl reagent prior to forming the first reaction product in the first mixture.

[0168] Embodiment 3. The method of Embodiment 1 or Embodiment 2, wherein contacting and combining take place at a temperature of about -30°C to about 0°C.

[0169] Embodiment 4. The method of any one of Embodiments 1-3, further comprising: isolating the second reaction product.

[0170] Embodiment 5. The method of any one of Embodiments 1-4, wherein the metal hydrocarbyl reagent is an organolithium compound.

[0171] Embodiment 6. The method of any one of Embodiments 1-3, wherein metal hydrocarbyl reagent is an organomagnesium compound.

[0172] Embodiment 7. The method of any one of Embodiments 1-6, wherein the Group 4 metal is zirconium or hafnium.

[0173] Embodiment 8. The method of any one of Embodiments 1-7, wherein the metal hydrocarbyl reagent is a metal alkyl reagent and the two hydrocarbyl leaving groups are two C1-C10alkyl groups.

[0174] Embodiment 9. The method of Embodiment 8, wherein the two hydrocarbyl leaving groups are each methyl.

[0175] Embodiment 10. The method of any one of Embodiments 1-9, wherein the ether solvent comprises at least one ether solvent selected from the group consisting of dimethoxy ethane, diethyl ether, 1,4-dioxane, methyl tert-butyl ether, tetrahydrofuran, and any combination thereof.

[0176] Embodiment 11. The method of any one of Embodiments 1-10, wherein the bridged bis(cyclopentadienyl) compound comprises an optionally substituted cyclopentadienyl ligand connected by a bridging group to an optionally substituted indenyl ligand.

[0177] Embodiment 12. The method of any one of Embodiments 1-11, wherein the bridged bis(cyclopentadienyl) compound has Cl symmetry.

[0178] Embodiment 13. The method of any one of Embodiments 1-12, wherein the Group 4 metal bridged bis(metallocene) complex has a structure represented by Formula 1:2025EM046-WG / 050930-0691R9R8Formula 1wherein: M is the Group 4 metal; T is a bridging group; X1and X2are each a C1-C10 hydrocarbyl leaving group; R1is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR', -OR', -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; R3is optionally substituted C1-C40 alkyl or optionally substituted C6-C14 aryl; R4and R5are independently H, R'", or OR'", wherein R'" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof; R6is independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR1,-OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl; R7, R8, R9, and R10are independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR', -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R7and R8, R8and R9, or R9and R10are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof.

[0179] Embodiment 14. The method of Embodiment 13, wherein T is CH2, CH2CH2, C(CH3)2, (Ph)2C, (p-(Et)3SiPh)2C, SiMe2, SiPh2, SiMePh, Si(CH2)3, or Si(CH2)4.

[0180] Embodiment 15. The method of Embodiment 13 or Embodiment 14, wherein R3is phenyl, 4-tert-butylphenyl, or 3,5-di-tert-butyl-4-methoxyphenyl.

[0181] Embodiment 16. The method of any one of Embodiments 13-15, wherein R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof.2025EM046-WG / 050930-0691

[0182] Embodiment 17. The method of any one of Embodiments 1-16, further comprising: contacting the Group 4 metal bridged bis(metallocene) complex with a support material.

[0183] Embodiment 18. The method of Embodiment 17, wherein the support material is silica.

[0184] Embodiment 19. The method of Embodiment 17 or Embodiment 18, further comprising depositing an activator upon the support material..

[0185] Embodiment 20. The method of Embodiment 19, wherein the activator comprises methylalumoxane (MAO).

[0186] Embodiment 21. A catalyst system comprising a Group 4 metal bridged bis(metallocene) complex formed by the method of any one of Embodiments 1-20, an activator, and optionally, a support, and optionally a scavenger or a co-activator.

[0187] Embodiment 22. A polymerization process comprising: providing an olefinic feed; and contacting the catalyst system of Embodiment 21 with the olefinic feed under polymerization reaction conditions to produce a polyolefin.

[0188] To facilitate a better understanding of the embodiments of the present disclosure, the following examples of preferred or representative embodiments are given. In no way should the following examples be read to limit, or to define, the scope of the invention.EXAMPLES

[0189] Preparation of Group 4 Metal Bridged Metallocene Catalysts. The following Group 4 bridged metallocene compounds were prepared according to the procedures provided below or procedures similar to those provided below.2025EM046-WG / 050930-0691Me2Si ZrCl2Me2Si HfCl2--zv^, " ’ tBu tBu Complex C1 Complex C2 Complex C4Me2Si ZrMe2Me2Si HfMe2tBu tBu Complex I1 Complex I2 Complex I3 Complex I4 Complex I5

[0190] Comparative Complexes C1-C3. Comparative Complexes C1-C3 (zirconium) were prepared according to previously published literature procedures as described in US Patent Application Publication 2022 / 0315680, which is incorporated herein by reference. Comparative Complex C4 (hafnium) was prepared similarly.

[0191] Inventive Complexes. Inventive Complexes 11-15 were prepared by one-pot reactions as outlined below.

[0192] Inventive Complex II. A small round bottom flask wrapped with aluminum foil was charged with 0.251 g (1.18 mmol) of ZrCh and 30 mL of dimethoxyethane (DME) and cooled to -20°C. When cold, 1.36 mL (2.18 mmol) of 1.6 M solution of MeLi was added and the mixture was stirred for 30 minutes. After 30 minutes, 0.55 g (1.08 mmol) dilithium (4-(4-tert-butylphenyl)-2-methyl-l,5,6,7-tetrahydro-s-indacenidyl)dimethyl(2,3,4,5-tetramethylcyclopentadienidyl)silane was added and the reaction mixture was stirred at -20°C for 1 hour. After 1 hour, the mixture was allowed to warm up to room temperature and was stirred overnight. After 18 hours, the mixture was concentrated in vacuo, and the residue was extracted with toluene (2 x 20 mL) and filtered over celite. The resulting brown toluene filtrate was then concentrated in vacuo to afford a tan powder. The powder was suspended in approximately 4 mL of pentane, filtered over a frit and washed with an additional 4 mL of pentane to afford 0.41 g of final product (74.9% yield).2025EM046-WG / 050930-0691NMR (400 MHz, C6D6): δ 7.79 (m, 2H) 7.45 (m, 2H) 7.34 (s, 1H) 7.15 (s, 1H) 2.94 (t, 2H), 2.73 (m, 2H) 1.95 (s, 3H) 1.91 (s, 3H) 1.87 (s, 3H) 1.85 (s, 3H) 1.81 (s, 3H) 1.27 (s, 9H), 0.84 (s, 3H) 0.65 (s, 3H) -0.09 (s, 3H) -1.06 (s, 3H).

[0193] Inventive Complex 12. A small round bottom flask was charged with 0.241 g (1.03 mmol) of ZrCl4and 25 mL of DME and cooled to -20 °C. When cold, 1.30 mL of 1.6 M solution of MeLi (2.09 mmol) was added and the mixture was stirred for 30 minutes. After 30 minutes, 0.73 g (1.03 mmol) dilithium(4-(3,5-ditert-4-methoxyphenyl)-2-methyl-l,5,6,7-tetrahydro-s-indacenidyl) dimethyl (2,3,4,5-tetramethylcyclopentadienidyl)silane (containing 1.75 equiv of diethylether) was added, and the reaction mixture was stirred at -20 °C for 1 h. After 1 h, the mixture was allowed to warm up to room temperature and was stirred overnight. After 18 hours, the mixture was concentrated in vacuo, and the residue was extracted with toluene (2 x 20 mL) and filtered over celite. The resulting yellow toluene filtrate was then concentrated in vacuo to afford off-white powder. The powder was suspended in about 4 mL of pentane, filtered over frit and washed with additional 4 mL of pentane to afford 0.36 g of final product (51% yield). 'H NMR (400 MHz, C6D6) δ 7.86 (s, 2H), 7.37 (s, 1H), 7.18 (s, 1H), 3.49 (s, 3H), 3.05 (m, 1H), 2.94 (m, 1H), 2.83 (m, 1H), 2.69 (m, 1H), 1.97 (s, 3H), 1.91 (s, 3H), 1.86 (s, 6H), 1.82 (s, 3H), 1.81 - 1.72 (m, 2H), 1.57 (s, 18H), 0.84 (s, 3H), 0.64 (s, 3H), -0.00 (s, 3H), -1.03 (s, 3H).

[0194] Inventive Complex 13. A small round bottom flask wrapped with aluminum foil was charged with 0.251 g (1.18 mmol) of ZrCl4and 30 mL of DME and cooled to -20°C. When cold, 1.36 mL (2.18 mmol) of a 1.6 M solution of MeLi was added and the mixture was stirred for 30 minutes. After 30 minutes, 0.55 g (1.08 mmol) of dilithium (4-phenyl)-2-methyl-l, 5,6,7-tetrahydro-s-indacenidyl)dimethyl(2,3,4,5-tetramethylcyclopentadienidyl)silane ligand was added, and the reaction mixture was stirred at -20°C for 1 h. After 1 h, the mixture was allowed to warm up to room temperature and was stirred overnight. After 18 hours, the mixture was concentrated in vacuo, and the residue was extracted with toluene (2 x 20 mL) and filtered over celite. The resulting brown toluene filtrate was then concentrated in vacuo to afford a tan powder. The powder was suspended in approximately 4 mL of pentane, filtered over a frit and washed with an additional 4 mL of pentane to afford 0.45 g of final product (76.8% yield).1H NMR (400 MHz, C6D6) δ 7.77 (m, 2H) 7.32 (m, 3H) 7.18 (m, 1H) 7.05 (s, 1H) 2.78 (m, 4H), 1.96 (s, 3H) 1.90 (s, 3H) 1.86 (s, 3H) 1.84 (s, 3H) 1.80 (m, 5H) 0.83 (s, 3H) 0.65 (s, 3H) -0.13 (s, 3H) -1.09 (s, 3H).2025EM046-WG / 050930-0691

[0195] Inventive Complex 14. A small round bottom flask wrapped with aluminum foil was charged with 0.292 g of HfCl4(0.912 mmol) and 20 mL of DME and cooled to -20°C. When cold, 1.15 mL (1.84 mmol) of a 1.6 M solution of MeLi was added and the mixture was stirred for 30 minutes. After 30 minutes, 0.5 g of dilithium (4-(4-tert-butylphenyl)-2-methyl-l,5,6,7-tetrahydro-s-indacenidyl)dimethyl(2,3,4,5-tetramethylcyclopentadienidyl)silane was added, and the reaction mixture was stirred at -20°C for 30 min. After 30 min, the mixture was allowed to warm up to room temperature and was stirred overnight. After 18 hours, the mixture was concentrated in vacuo, and the residue was extracted with toluene (2 x 10 mL) and fdtered. Solvent was removed in vacuo and the residue was triturated with pentane (5 mL), the precipitated solid was collected on a frit and dried in vacuo to afford 0.35 g of final product as pale yellow solid (55.9% yield).1H NMR (400 MHz, C6D6): δ 7.79 (m, 2H) 7.47 (m, 2H) 7.39 (s, 1H) 7.04 (s, 1H) 2.94 (t, 2H), 2.73 (m, 2H) 2.01 (s, 3H) 1.91 (s, 6H) 1.87 (s, 3H) 1.85 (s, 3H) 1.81 (m, 2H) 1.27 (s, 9H), 0.86 (s, 3H) 0.67 (s, 3H) -0.24 (s, 3H) -1.22 (s, 3H).

[0196] Inventive Complex 15. To a precooled (-20°C), stirring suspension of zirconium chloride (48.7 mg, 209 μmol) in diethyl ether (3 mL), a mixture of benzylmagnesium chloride solution (0.42 mL, 1.00 M in diethyl ether, 0.42 mmol, 2 equiv) and dilithium (4-(4-tert-butylphenyl)-2-methyl-l,5,6,7-tetrahydro-s-indacenidyl)dimethyl(2,3,4,5-tetramethylcyclopentadienidyl)silane(116.6mg, 211 μmol, 1 equiv)) in diethyl ether (10 mL) was added. The reaction was stirred while covered in foil and allowed to warm to room temperature overnight. The reaction was concentrated under a stream of nitrogen and then under high vacuum. The residue was extracted with hexane and filtered over Celite. The hexane extract was concentrated under a stream of nitrogen and then under high vacuum to afford the product, containing residual diethyl ether (0.58 equiv) and hexane (0.81 equiv) (164 milligrams (mg), 89.7% yield).1H NMR (400 MHz, C6D6) major isomer: δ 7.39 (s, 1H), 7.35 (d, 2H, J = 8.5 Hz), 7.25 (d, 2H, J = 8.5 Hz), 7.13-7.06 (m, 3H), 6.97-6.91 (m, 2H), 6.90-6.80 (m, 3H), 6.80-6.75 (m, 2H), 6.22 (s, 1H), 3.11-2.99 (m, 1H), 2.90-2.57 (m, 5H), 2.01 (s, 3H), 1.87 (s, 3H), 1.86 (s, 3H), 1.76 (s, 3H), 1.56 (d, 1H, J = 11.7), 1.36 (s, 9H), 1.18 (s, 3H), 0.85 (s, 3H), 0.68 (s, 3H), -0.19 (s, 3H). Two protons are unaccounted for and are believed to be obscured by solvent signals.

[0197] Stepwise Complexes. Stepwise Complex S2 (identical chemical structure as Inventive Complex 12) was prepared by a two-pot reaction (first reaction to prepare Comparative (di chloride) Complex C2, second reaction to prepare Inventive (dimethyl) comples 12, as outlined below.2025EM046-WG / 050930-0691

[0198] Stepwise Complex S2 (prepared via stepwise alkylation of C2). A small round bottom flask was charged with Comparative (dichloride) Complex C2 (0.50 g, 0.688 mmol) and 20 mL of toluene. 0.629 mL of 3.28 M solution of MeMgBr was then added which resulted in instant color change from orange to yellow accompanied with some salt precipitation. The reaction mixture was then heated to 80°C. After 4 hours, the reaction showed clean conversion to ZrMe2 species with about 25% remaining complex as Zr(Me)Cl. The reaction mixture was further stirred and heated overnight. After 18 hours, the reaction mixture was concentrated in vacuo and re-extracted with benzene (3 x 10 mL), and filtered over celite. Solvent removal afforded the product (0.395 g, 83.7% yield).

[0199] Preparation of Supported Metallocene Catalyst Systems using Group 4 Metal Bridged Metallocene Catalysts. The Group 4 bridged metallocene complexes from above (Comparative Complexes C1-C3, Inventive Complexes 11-15, and Stepwise Complex S2) were used to prepare the corresponding supported metallocene catalyst systems. The supported metallocene catalyst systems were prepared according to the following general procedure. 2.0 g of silica supported MAO (containing approximately 4.7 mmol of MAO / g of DM-L403 silica from Asahi Glass Chemical) was placed in a vial along with 10 mL of toluene. While vortexing, 32.8 μmol of the Group 4 bridged metallocene complex was added. The mixture was vortexed for 3 h, solvent was then filtered off and the powder was washed with toluene (2 x 5 mL) and pentane (2 x 5 mL) and dried in vacuo. The resulting powders were suspended in mineral oil to make a slurry containing 5 wt% solids.

[0200] Reactivity of Group 4 Metal Bridged Metallocene Catalyst with MAO. In order to gain better understanding of activated species, a small-scale reactivity study was carried out by proton nuclear magnetic resonance (1H NMR). Complexes Cl and II were reacted identically with MAO in CeDe, and the reaction products were analyzed in situ by NMR (FIGURE). A single t-butyl (tBu) peak was observed for Complex I1 In contrast, multiple tBu peaks were observed for Complex C1 The multiple tBu peaks for Complex C1 are believed to arise from incomplete activation of the dichloride complex. Therefore, it may be concluded that higher activation efficiencies may be achieved starting from methyl leaving groups, leading to improved catalyst activities.

[0201] Polymerization of Alpha Olefins. The catalyst systems prepared above were tested for propylene polymerization under standard conditions by using 25 mg of dry catalyst and 8 mmol2025EM046-WG / 050930-0691of hydrogen (H2). A 2 L autoclave equipped with a steam jacket and mechanical stirrer was nitrogen purged and heated to 130°C for at least 1 hour. Upon cooling to room temperature, liquid propylene (600 mL), triisobutylaluminum (0.4 - 1.0 mL of 1 M solution in hexane) and hydrogen (8 mmol) were added and allowed to mix for 5 minutes. After 5 minutes, catalyst slurry (25 mg of dry catalyst) was flushed in the reactor along with 200 mL of liquid propylene. The contents of the reactor were allowed to mix for 5 minutes (pre-polymerization stage), before the reactor temperature was raised to 70°C to start the polymerization. After 30 minutes, the reactor was cooled to room temperature, unreacted propylene was vented, and the polymer was collected and allowed to dry overnight.

[0202] Properties of the polypropylenes produced using catalyst systems containing Complexes C1-C3 and 11-15 are summarized in Table 1 below. Despite having significantly improved activities (see Table 2 below), the metallocene catalyst systems based on Complexes 11-15 demonstrated no sacrifices in polymer properties, as similar poly dispersity values and polymer melting points were achieved. Polymer molecular weight values were determined according to gel permeation chromatography with 4 detectors (GPC-4D). An added benefit is the relatively lower hydrogen response of Complexes 11-15, as generally reduced melt flow rates (MFR), determined according to ASTM1238 at 190°C and a load of 2.16 kg, were obtained under identical polymerization conditions.

[0203] Peak melting point, Tm, described for larger scale reactor batches (also referred to as melting point) and peak crystallization temperature, Tc, (also referred to as crystallization temperature) were determined using the following DSC procedure. Differential scanning calorimetric (DSC-2) data was obtained using a TA Instruments model DSC2500 machine. Samples weighing approximately 5 to 10 mg were sealed in an aluminum hermetic sample pan and loaded into the instrument at about room temperature. The DSC data were recorded by first gradually heating the sample to 220°C at a rate of 10°C / minute in order to erase all thermal history. The sample was kept at 220°C for 5 minutes, then cooled to -10°C at a rate of 10°C / minute, followed by an isothermal hold for 5 minutes and heating to 220°C at 10°C / minute, holding at 220°C for 5 minutes and then cooling down to 25°C at a rate of 10°C / minute. Both the first and second cycle thermal events were recorded. The melting and crystallization temperatures reported here were obtained during the second heating / cooling cycle unless otherwise noted.Table 1Complex MFR MnMwMzMw / MnMz / MwTmTc(g / 10 min) (g / mol) (g / mol) (g / mol) (°C) (°C) C1 66.3 43,094 138,286 306,907 3.21 2.22 159.1 117.2 C2 69.5 47,546 140,360 282,442 2.95 2.01 160.7 118.2 C3 61.8 44,874 137,018 289,490 3.05 2.11 156.5 114.9 I1 39.6 47,596 144,814 291,072 3.04 2.01 158.9 116.7 I2 39.9 51,256 147,446 283,327 2.88 1.92 159.9 116.5 I3 56.5 45,908 137,349 279,453 2.99 2.03 157.4 115.7 I5 47.8 48,059 148,776 324,208 3.10 2.18 158.5 116.2

[0204] As shown in Table 2, Complexes I1-I3 exhibited significantly improved activities compared to the corresponding Complexes C1-C3. Based on the data, it is evident that zirconocene dialkyl analogs of Cl symmetric metallocene catalysts provide improved activation efficiency relative to dichlorides. Further, it is evident that one-pot synthesis of zirconocene dialkyl Cl symmetric metallocene catalysts further increases the catalyst activity, as compared to the same catalysts prepared by stepwise synthesis.Table 2Complex Leaving Catalyst Activity IncreaseGroup Type Activity Relative to(g / g-h) ComparativeComplexCl Chloride 6374 ___C2 Chloride 7336 ___C3 Chloride 5387 ___I1 Methyl 12,368 48%S2 Methyl 14,161 48%I2 Methyl 20,960 65%I3 Methyl 9,109 41%I5 Benzyl 9,439 43%

[0205] All documents described herein are incorporated by reference herein for purposes of all jurisdictions where such practice is allowed, including any priority documents and / or testing2025EM046-WG / 050930-0691procedures to the extent they are not inconsistent with this text. As is apparent from the foregoing general description and the specific embodiments, while forms of the disclosure have been illustrated and described, various modifications can be made without departing from the spirit and scope of the disclosure. Accordingly, it is not intended that the disclosure be limited thereby. For example, the compositions described herein may be free of any component, or composition not expressly recited or disclosed herein. Any method may lack any step not recited or disclosed herein. Likewise, the term “comprising” is considered synonymous with the term “including.” Whenever a method, composition, element or group of elements is preceded with the transitional phrase “comprising,” it is understood that we also contemplate the same composition or group of elements with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “is” preceding the recitation of the composition, element, or elements and vice versa.

[0206] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by one or more embodiments described herein. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0207] Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces.

[0208] One or more illustrative embodiments are presented herein. Not all features of a physical implementation are described or shown in this application for the sake of clarity. It is understoodthat in the development of a physical embodiment of the present disclosure, numerous implementation-specific decisions must be made to achieve the developer's goals, such as compliance with system-related, business-related, government-related and other constraints, which vary by implementation and from time to time. While a developer's efforts might be time-consuming, such efforts would be, nevertheless, a routine undertaking for one of ordinary skill in the art and having benefit of this disclosure.

[0209] Therefore, the present disclosure is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present disclosure may be modified and practiced in different but equivalent manners apparent to one having ordinary skill in the art and having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present disclosure. The embodiments illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and / or any optional element disclosed herein.

Claims

2025EM046-WG / 050930-0691CLAIMSThe invention claimed is:

1. A method comprising:contacting a Group 4 metal tetrahalide and a metal hydrocarbyl reagent in an ether solvent, thereby forming a first reaction product in a first mixture; and,without isolating the first reaction product, combining the first mixture with a dilithium salt of a bridged bis(cyclopentadienyl) compound, thereby forming a second reaction product in a second mixture, the second reaction product comprising a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups.

2. The method of claim 1, wherein combining the first mixture with the dilithium salt comprises combining the dilithium salt with the Group 4 metal tetrahalide and the metal hydrocarbyl reagent prior to forming the first reaction product in the first mixture.

3. The method of claim 1, wherein contacting and combining take place at a temperature of about -30°C to about 0°C.

4. The method of claim 1, further comprising:isolating the second reaction product.

5. The method of any preceding claim,(i) wherein the metal hydrocarbyl reagent is (1) an organolithium compound or (2) an organomagnesium compound;(ii) wherein the Group 4 metal is zirconium or hafnium;(iii) wherein the metal hydrocarbyl reagent is a metal alkyl reagent and the two hydrocarbyl leaving groups are two Cl -CIO alkyl groups;(iv) wherein the ether solvent comprises at least one ether solvent selected from the group consisting of dimethoxy ethane, diethyl ether, 1,4-di oxane, methyl tert-butyl ether, tetrahydrofuran, and any combination thereof;(v) wherein the bridged bis(cyclopentadienyl) compound comprises an optionally substitutedcyclopentadienyl ligand connected by a bridging group to an optionally substituted indenyl ligand; or(vi) any combination of (i) - (v).

6. The method of claim 5, wherein the two hydrocarbyl leaving groups are each methyl.

7. The method of claim 5, wherein the bridged bis(cyclopentadienyl) compound has Ci symmetry.

8. The method of any preceding claim, wherein the Group 4 metal bridged bis(metallocene) complex has a structure represented by Formula 1R9R8Formula 1wherein:M is the Group 4 metal;T is a bridging group;X1and X2are each a Cl -CIO hydrocarbyl leaving group;R1is hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted Cg-Cu aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR1, -OR’, -SiR’3, -OSiR'3,-PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl;R3is optionally substituted C1-C40 alkyl or optionally substituted C6-C14 aryl;R4and R5are independently H, R'", or OR'", wherein R'" is an optionally substituted C1-C40 alkyl, or R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof;R6is independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted Ce-Ci4 aryl, optionally substituted C4-C13 heteroaryl, -NR'2, -SR',-OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl;R7, R8, R9, and R10are independently hydrogen, halogen, optionally substituted C1-C40 alkyl, optionally substituted C6-C14 aryl, optionally substituted C4-C13heteroaryl, -NR'2, -SR1, -OR’, -SiR'3, -OSiR'3, -PR'2, or -R"-SiR'3, wherein R" is C1-C10 alkyl and R' is hydrogen, C1-C10 alkyl, or C6-C10aryl, or one or more of R7and R8, R8and R9, or R9and R10are joined to form a C -C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof.

9. The method of claim 8, wherein T is CH2, CH2CH2, C(CH3)2, (Ph)2C,(p-(Et)3SiPh)2C, SiMe2, SiPh2, SiMePh, Si(CH2)3, or Si(CH2)4.

10. The method of claim 8, wherein R3is phenyl, 4-tert-butylphenyl, or 3, 5 -di -tert-butyl -4-methoxyphenyl.

11. The method of claim 8, wherein R4and R5are joined to form a C3-C62 optionally substituted, saturated or unsaturated, cyclic or polycyclic ring structure, or a combination thereof.

12. The method of claim 1 or 8, further comprising:contacting the Group 4 metal bridged bis(metallocene) complex with a silica support material.

13. The method of claim 12, further comprising depositing an activator upon the support material, wherein the activator comprises methylalumoxane (MAO).

14. A catalyst system comprising a Group 4 metal bridged bis(metallocene) complex having two hydrocarbyl leaving groups formed by the method of claim 1 or 8, an activator, and optionally, a support, and optionally a scavenger or a co-activator.

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