Palladium complex modified by norcamphane skeleton monophosphine ligand as well as preparation method and application of palladium complex

Abstract

The invention provides an norcamphane skeleton monophosphine ligand L modified palladium complex as well as a preparation method and application thereof. The palladium complex has a structure represented by the formula wherein L is an norcamphane skeleton monophosphine ligand having the structure represented by the formula, and Ar, R1, and R2 are as defined herein. The palladium complex may be prepared by reacting halogenated norbornene or an analog thereof with an aryl halide or an aryl sulfonate in the presence of an organic solvent and a palladium catalyst; reacting the obtained intermediate with R1R2PCl; and reacting the obtained ligand L with a palladium precursor and 2-(trimethylsilyl) ethyl-4-bromophenylmethyl ester. The palladium complex disclosed by the invention not only can be used as a catalyst for promoting a C-N coupling reaction in the synthesis of an organic compound containing a C-N structural unit, but also can reduce the dosage of the catalyst and expand the application range of efficient catalytic reaction due to the unique rigid skeleton and remarkable three-dimensional space characteristics of norcamphane molecules.

Description

Technical Field

[0001] This invention relates to the fields of organic synthesis and catalysis, and more specifically to palladium complexes modified with a norbornene skeleton monophosphine ligand, their preparation methods, and applications. Background Technology

[0002] Transition metal catalysis is a crucial component of organic synthesis, and its research has always been a focal point of scientific study. The core of transition metal catalysis lies in ligands, as they can directly determine the activity and selectivity of catalytic reactions by precisely controlling the electronic properties and spatial configuration of the metal center. Therefore, the design and development of novel ligands has consistently been a key research direction driving the advancement of this field.

[0003] Among these, phosphine ligands occupy a central position in cross-coupling reactions catalyzed by transition metals, due to their strong coordination ability and tunable spatial and electronic properties, which enable precise control of key steps in the catalytic process.

[0004] CN bonds are important structural units in pharmaceutical, pesticide, and functional material molecules. The Buchwald–Hartwig amination reaction is the cornerstone reaction for constructing CN bonds, providing a crucial pathway for efficiently obtaining structurally diverse nitrogen-containing compounds. Since the 1990s, one of the research focuses has been on improving reaction efficiency, chemoselectivity, and regioselectivity through rational ligand design. Against this backdrop, monodentate biaryl and heteroaryl phosphine ligands have become a class of advantageous skeletons, skillfully balancing steric hindrance and electron-donating capabilities. Examples include the biphenyl dialkylphosphine ligand developed by the Buchwald group (Chem. Rev., 2016, 116, 12564) and the bispyrazole phosphine ligands reported by the Singer group (Isr. J.Chem., 2020, 60, 294). Zhu Shoufei's research group has developed a class of monophosphine ligands with a cyclopropane skeleton. The complexes formed by these ligands and palladium can be used as catalysts in the Buchwald-Hartwig reaction and the Suzuki-Miyaura reaction (see, for example, CN116535439A, CN119101084A, Angew. Chem. Int. Ed. 2023, 62, e202309111, etc.).

[0005] However, current exploration of the skeletal structure of monophosphine ligands remains limited, and their catalytic potential requires further exploration and systematic evaluation. Therefore, the design and development of novel phosphine ligands and corresponding catalysts are still needed in this field to expand the applicability of highly efficient catalytic reactions, which has significant theoretical and practical implications. Summary of the Invention

[0006] One objective of this invention is to provide a novel single-phosphine ligand and its corresponding palladium complex catalyst, as well as a method for preparing the same, to overcome the shortcomings of existing technologies. Another objective of this invention is to explore and verify the catalytic activity and substrate applicability of this type of ligand and its palladium complex catalyst in CN coupling, thereby expanding the scope of applications for highly efficient catalytic reactions.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] In one aspect, the present invention provides a palladium complex modified with a norbornene skeleton monophosphine ligand L, the palladium complex having a structure represented by the formula L-Pd-G6:

[0009]

[0010] Where L is a group consisting of... The structure represented is a norbornene skeleton monophosphine ligand, and the ligand L is connected to the metal Pd atom of the palladium complex via a P atom to form the complex, wherein Ar is selected from C. 6-10 Aryl or C 6-10 heteroaryl; R 1 and R 2 Each is independently selected from C that is arbitrarily substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 2-8 Alkenyl, C substituted with one or more halogens 2-8 Alkyne group, C group optionally substituted with one or more halogens 3-8 cycloalkyl, C 6-10 Aryl or C 6-10 heteroaryl, of which the C mentioned above 6-10 Aryl or C 6-10 Each heteroaryl group is independently selected from 1 to 5 groups chosen from C. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Alkoxy, halogen, hydroxyl, amino, C 1-8 Alkylamino, diC 1-8 Alkylamino, C 1-8 Acyl group, C 2-8 Acyloxy group, C 2-8 ester group or C 1-8 The acylamino group is substituted, and the C 6-10 The heteroaryl group contains 1-3 heteroatoms selected from N, S or O; and TMS is trimethylsilyl.

[0011] In some preferred embodiments, in the ligand L, Ar is selected from phenyl or naphthyl, wherein each of the phenyl or naphthyl groups is independently optionally composed of 1-3 C-terminal groups. 1-8 Alkyl, Halogenated C1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

[0012] In some preferred embodiments, in the ligand L, R 1 and R 2 Each is independently selected from C that is arbitrarily substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 3-8 Cycloalkyl or phenyl, wherein the phenyl group is optionally composed of 1-3 C16 atoms. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

[0013] In some preferred embodiments, the palladium complex has a structure represented by the formula L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6, or L8-Pd-G6, or a racemic or enantiomer thereof:

[0014]

[0015] L1, L2, L3, L4, L5, L6, L7, and L8 are the norcamphorane skeleton monophosphine ligands of complexes L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6, or L8-Pd-G6, respectively.

[0016] In another aspect, the present invention provides a method for preparing the above-mentioned palladium complex, the method comprising:

[0017] In the presence of an organic solvent and a palladium catalyst, halogenated norbornene or its analogues are subjected to a hydroarylation reaction with aryl halides or aryl sulfonates to obtain aryl-substituted halogenated norbornene intermediate S2.

[0018] Make the intermediate S2 and R 1 R 2 PCl undergoes a substitution reaction to yield the norcamphorane skeleton monophosphine ligand L;

[0019] The norcamphor skeleton monophosphine ligand L is reacted with palladium precursor S3 and 2-(trimethylsilyl)ethyl-4-bromobenzyl ester to obtain the desired palladium complex.

[0020] , where cod represents 1,5-cyclooctadiene.

[0021] In some preferred embodiments, the ligand L obtained from the substitution reaction undergoes an addition reaction with a borane solution to obtain the borane adduct of the ligand L, L-BH3:

[0022]

[0023] Furthermore, if necessary, the adduct L-BH3 can be deprotected from its borane protecting group in the presence of an organic base deprotecting agent to obtain the norcamphorane skeleton monophosphine ligand L.

[0024] In some preferred embodiments, the hydroarylation reaction is carried out in the presence of a negative hydrogen source, preferably triethylamine and formic acid; preferably the hydroarylation reaction is carried out at 0-150°C; preferably the organic solvent is one or more selected from dimethyl sulfoxide, benzene, toluene, tetrahydrofuran, ethyl acetate and acetonitrile.

[0025] In some preferred embodiments, in relation to R 1 R 2 Before the substitution reaction of PCl, the intermediate S2 is subjected to a lithium halide exchange reaction with alkyl lithium; preferably, the alkyl lithium is tert-butyl lithium or n-butyl lithium.

[0026] In another aspect, the present invention provides an adduct L-BH3 of a norcamphorane skeleton monophosphine ligand L and borane for preparing the above-mentioned palladium complex, said adduct having the following structure:

[0027] .

[0028] In another aspect, the present invention provides the application of the above-mentioned palladium complex as a catalyst in promoting CN coupling reactions in organic synthesis, preferably the palladium complex is used in combination with the above-mentioned adduct L-BH3.

[0029] In another aspect, the present invention provides an organic compound, preferably a pharmaceutical, pesticide, or functional material compound, said organic compound containing a CN structural unit formed by a CN coupling reaction promoted by using the above-mentioned palladium complex as a catalyst, preferably the palladium complex being used in combination with the above-mentioned adduct L-BH3.

[0030] This invention provides a novel norunane skeleton monophosphine ligand, its borane adduct, and palladium complex. The ligand and palladium complex of this invention (optionally used in combination with the corresponding borane adduct L-BH3) exhibit excellent catalytic activity and broad substrate applicability in CN coupling, significantly improving reaction efficiency and regioselectivity, demonstrating good application potential and broad market prospects.

[0031] Furthermore, the palladium complex of the present invention can not only be used as a catalyst to promote CN coupling reaction, but also reduce the amount of catalyst required and expand the applicability of highly efficient catalytic reactions due to the unique rigid skeleton and significant three-dimensional spatial characteristics of its norbornene molecule. Detailed Implementation

[0032] During their in-depth and extensive research, the inventors unexpectedly discovered that, compared to phosphine ligands such as biphenyl dialkyl skeletal phosphine ligands, bispyrazole skeletal phosphine ligands, and cyclopropane skeletal phosphine ligands used in the prior art, norcamphene molecules, due to their unique rigid skeleton and significant three-dimensional spatial characteristics, can provide an ideal skeleton structure for developing novel phosphine ligands with novel spatial and electronic properties.

[0033] Based on this discovery, the present invention provides a norcamphorane skeleton monophosphine ligand L having the following structure:

[0034]

[0035] In this ligand L, Ar is C 6-10 Aryl or C 6-10 heteroaryl; R 1 and R 2 Each is independently selected from C that is arbitrarily substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 2-8 Alkenyl, C substituted with one or more halogens 2-8 Alkyne group, C group optionally substituted with one or more halogens 3-8 cycloalkyl, C 6-10 Aryl or C 6-10 Mixed aromatic compounds.

[0036] In the above Ar, R 1 and R 2 The definition of C mentioned 6-10 Aryl and C 6-10 Each heteroaryl group can be independently and selectively co-occurring with 1-5 groups selected from C. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Alkoxy, halogen, hydroxyl, amino, C 1-8 Alkylamino, diC 1-8 Alkylamino, C 1-8 Acyl group, C 2-8 Acyloxy group, C 2-8 ester group or C 1-8 Substituents of the acylamino group, and the C mentioned 6-10 Heteroaryl groups are C groups containing 1-3 heteroatoms selected from N, S, or O. 6-10 Aryl.

[0037] In this invention, preferably, Ar can be phenyl or naphthyl, each of which can be independently and optionally composed of 1-3 C atoms selected from C. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

[0038] In this invention, preferably, R 1 and R 2 It can be independently selected from C that is optionally substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 3-8 Cycloalkyl or phenyl, wherein the phenyl group may optionally be composed of 1-3 C-12 groups. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

[0039] As used in this article, the term "C" 1-8 "Alkyl" refers to a straight-chain or branched hydrocarbon group having 1 to 8 carbon atoms. Preferably, C 1-8 Examples of alkyl groups can be methyl, ethyl, n-propyl, isopropyl ( i Pr), cyclopropyl, n-butyl (Bu), isobutyl ( i Bu), sec-butyl ( s Bu), tert-butyl ( t Bu), n-pentyl, isopentyl, neopentyl, sec-pentyl, tert-pentyl, n-hexyl, isopentyl, neohexyl, sec-hexyl, tert-hexyl, n-heptyl, isopentyl, neoheptyl, sec-heptyl, tert-heptyl, n-octyl, isopentyl, neooctyl, sec-octyl or tert-octyl.

[0040] As used in this article, the term "halogen" refers to fluorine, chlorine, bromine, or iodine.

[0041] As used in this article, the term "halogenated C" 1-8 "Alkyl" refers to a C that has been substituted with one or more halogens. 1-8 Alkyl groups, examples of which may include, but are not limited to, trifluoromethyl groups.

[0042] As used in this article, the term "C" 1-8 "Alkoxy" refers to the group C 1-8 Alkyl-O-, examples of which may include, but are not limited to, methoxy, ethoxy, tert-butoxy, etc.

[0043] As used in this article, the term "hydroxyl group" refers to the -OH group.

[0044] As used herein, the term "amino" refers to the group -NH2.

[0045] As used in this article, the term "C" 1-8 "alkylamino" refers to the group -NHC 1-8 Alkyl group, i.e., one hydrogen atom of the above amino group is C 1-8 Examples of alkyl-substituted amino groups may include, but are not limited to, -NHCH3.

[0046] As used in this article, the term "two C" 1-8 "alkylamino" refers to the group -N(C) 1-8 Alkyl)2, that is, the two hydrogen atoms in the above amino group are C 1-8 Examples of alkyl-substituted amino groups may include, but are not limited to, -N(CH3)2.

[0047] As used in this article, the term "C" 1-8 "Acyl" refers to an acyl group having 1 to 8 carbon atoms, and examples of acyl groups include, but are not limited to, formyl, acetyl, propionyl, n-butyryl, isobutyryl, n-valeryl, isovaleryl, sec-valeryl, neovaleryl, n-hexanoyl, isohexanoyl, neohexanoyl, sec-hexanoyl, n-heptanoyl, isoheptanoyl, neoheptanoyl, sec-heptanoyl, n-octanoyl, isooctanoyl, neooctanoyl, sec-octanoyl, 1-cyclopropylformyl, 1-cyclobutylformyl, 1-cyclopentylformyl, 1-cyclohexylformyl, or 1-cycloheptylformyl.

[0048] As used in this article, the term "C" 2-8 "Acyloxy group" refers to the group C 1-8 Alkyl-C(O)-O-, examples of which may include, but are not limited to, acetoxy, propionyloxy, n-butyryloxy, isobutyryloxy, n-valeryloxy, isovaleryloxy, sec-valeryloxy, neovaleryloxy, n-hexanoyloxy, isohexanoyloxy, neohexanoyloxy, sec-hexanoyloxy, n-heptanoyloxy, isoheptanoyloxy, neoheptanoyloxy, sec-heptanoyloxy, n-octanoyloxy, isooctanoyloxy, neooctanoyloxy, sec-octanoyloxy, 1-cyclopropylformyloxy, 1-cyclobutylformyloxy, 1-cyclopentylformyloxy, 1-cyclohexylformyloxy or 1-cycloheptylformyloxy.

[0049] As used in this article, the term "C" 2-8 "Ester group" refers to the C group. 1-8 Alkyl-OC(O)-, examples of which may include, but are not limited to, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, n-pentoxycarbonyl, isopentoxycarbonyl, neopentoxycarbonyl, secondary pentoxycarbonyl, tertiary pentoxycarbonyl, cyclopentoxycarbonyl, n-hexyloxycarbonyl, isohexyloxycarbonyl, neohexyloxycarbonyl, secondary hexyloxycarbonyl, tertiary hexyloxycarbonyl, cyclohexyloxycarbonyl, n-heptoxycarbonyl, isoheptoxycarbonyl, neoheptoxycarbonyl, secondary heptaoxycarbonyl, tertiary heptaoxycarbonyl, or cycloheptoxycarbonyl.

[0050] As used in this article, the term "C" 1-8 "Acylamino" refers to the group -NHC 1-8 The acyl group, i.e., one hydrogen atom of the above amino group is C 1-8 Amino groups substituted with acyl groups.

[0051] The present invention further provides a palladium complex modified with the above-mentioned norbornene skeleton monophosphine ligand L, the palladium complex having a structure represented by the following formula L-Pd-G6:

[0052]

[0053] TMS stands for trimethylsilyl.

[0054] The palladium complex of the present invention can be prepared by the following method, which includes: in the presence of an organic solvent and a palladium catalyst, reacting a halobornene or its analogue with an aryl halide or an aryl sulfonate to undergo a hydroarylation reaction to obtain an aryl-substituted halobornenane intermediate S2; reacting the intermediate S2 with R 1 R 2 PCl undergoes a substitution reaction to give a norcamphor skeleton monophosphine ligand L; the norcamphor skeleton monophosphine ligand L is then reacted with palladium precursor S3 and 2-(trimethylsilyl)ethyl-4-bromobenzyl ester to obtain the desired palladium complex.

[0055] In the method of the present invention, there are no particular limitations on the organic solvent used in the hydroarylation reaction. Preferably, the organic solvent used may be one or more selected from dimethyl sulfoxide, benzene, toluene, tetrahydrofuran, ethyl acetate, or acetonitrile.

[0056] In the method of the present invention, the palladium catalyst used in the hydroarylation reaction is known in the art, for example, it can be a palladium metal complex, such as palladium acetate (Pd(OAc)2) coordinated with organophosphorus ligand L'.

[0057] ,

[0058] The ligand L' can be synthesized using the method described in the literature (Org. Lett., 2004, 6, 4105-4107).

[0059] In the method of the present invention, the halobornene S1 used can be as shown in the following formula:

[0060] Where X represents a halogen, preferably I or Br. In this invention, the halogenated norbornene used can be obtained directly from commercial purchases, or prepared from norbornene as a starting material via a halogenation substitution reaction known in the art.

[0061] In the method of this invention, the aryl halide used can be represented by the formula ArX', where X' represents a halogen such as I or Br, or a sulfonate group such as a methanesulfonate group (OTf). Similarly, the aryl halide used in this invention is well known in the art and can be commercially available or prepared by conventional methods using halogenation substitution reactions of aromatic hydrocarbons.

[0062] In the method of the present invention, preferably, the hydroarylation reaction is carried out in the presence of a negative hydrogen source. More preferably, the negative hydrogen sources that can be used include, but are not limited to, triethylamine, formic acid, or mixtures thereof.

[0063] In the method of the present invention, preferably, the hydroarylation reaction can be carried out at 0-150°C, for example, about 120°C.

[0064] In the method of the present invention, there is no particular limitation on the time of the hydrogen arylation reaction, for example, it can be carried out for 1-24 hours.

[0065] In the method of the present invention, the intermediate S2 obtained by the hydrogenation reaction can be expressed as follows:

[0066] Where X represents a halogen such as I or Br, and Ar represents an aryl or heteroaryl group as defined above.

[0067] In the method of the present invention, preferably, in relation to R 1 R 2 Before PCl undergoes a substitution reaction, intermediate S2 undergoes a lithium halide exchange reaction with an alkyl lithium. More preferably, intermediate S2 undergoes a lithium halide exchange reaction with an alkyl lithium such as tert-butyllithium or n-butyllithium.

[0068] In the method of the present invention, during the synthesis of ligand L, the ligand L obtained by the substitution reaction can preferably undergo an addition reaction with a borane solution, such as a tetrahydrofuran solution of borane, to obtain the borane adduct of ligand L as shown in the following formula: L-BH3.

[0069] Ar and R 1 and R 2 As defined above.

[0070] The inventors have discovered that forming the above-mentioned adduct L-BH3 with a borane solution can effectively prevent the oxidation of ligand L, i.e., borane BH3 acts as a protecting group for ligand L. Furthermore, if necessary, for example when L is needed to synthesize palladium complexes, the borane protecting group can be removed first using a suitable organic base remover to obtain the norbornene skeleton monophosphine ligand L before proceeding to the next synthesis step. Preferably, examples of usable organic base removers include, but are not limited to, organic bases such as triethylenediamine (DBACO). In addition, it has been found that when the adduct L-BH3 of the present invention is used in combination with the palladium complex of the present invention, it can exert a more efficient catalytic effect. Furthermore, the adduct L-BH3 of the present invention can also be used with other palladium catalysts in the prior art, which can similarly enhance their catalytic performance.

[0071] In the method of the present invention, the palladium precursor S3 that can be used has the following structure:

[0072] Where cod represents 1,5-cyclooctadiene. This palladium precursor S3 is known in the art; for example, Ryan R. King et al. (“A Neophyl Palladacycle as an Air and Thermally Stable Precursor to Oxidative Addition Complexes”, Organic Letters, 2021, 23, 7927-7932) described a method for preparing this palladium precursor as follows:

[0073]

[0074] In the method of this invention, the reaction scheme for reacting intermediate L, palladium precursor S3, and 2-(trimethylsilyl)ethyl-4-bromophenyl ester to obtain the target complex is as follows:

[0075]

[0076] This reaction can be carried out, for example, in an organic solvent such as hexane under heating, for example at 60°C.

[0077] In a particular embodiment, the method of the present invention can be implemented according to the following scheme:

[0078] .

[0079] In this invention, preferably, the provided palladium complex may have a structure represented by the formula L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6 or L8-Pd-G6, or its racemic or enantiomer:

[0080]

[0081] Here, L1, L2, L3, L4, L5, L6, L7, and L8, listed in the dashed boxes on the right of each formula, are the corresponding norbornene skeleton monophosphine ligands L in the complexes L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6, or L8-Pd-G6.

[0082] The palladium complexes of the present invention can be applied in many fields, particularly for promoting CN coupling reactions in organic synthesis. Organic synthesis as mentioned herein includes, but is not limited to, the synthesis of organic compounds containing CN structural units, such as pharmaceuticals, pesticides, and functional material molecules, more specifically, the formation of CN structural units in such organic compounds, particularly pharmaceuticals, pesticides, and functional material compounds, through CN coupling reactions promoted using the palladium complexes of the present invention as catalysts. For example, the palladium complexes of the present invention can be used as catalysts to promote CN coupling reactions in the Buchwald–Hartwig amination reaction and the Suzuki-Miyaura reaction, preferably in combination with the aforementioned adduct L-BH3. It has been found that by using the palladium complexes of the present invention as catalysts, CN coupling reactions in the Buchwald–Hartwig amination reaction and the Suzuki-Miyaura reaction can be promoted, yielding the desired product in higher yields. Furthermore, compared to existing phosphine ligand catalysts, when using the palladium complexes of the present invention as catalysts, preferably in combination with the aforementioned adduct L-BH3, highly efficient catalytic effects can be achieved with lower catalyst dosages.

[0083] For example, the palladium complex (L-Pd-G6) and borane adduct (L-BH3) of the present invention can be used together as catalysts to promote the synthesis of triarylamines, N-alkylanilines, secondary amines, sterically hindered anilines, aryl chlorides, heteroaryl bases, or suitable drug molecules. The specific reaction scheme can be as follows:

[0084]

[0085] Where R and R' can independently represent alkyl, aryl, or heteroaryl groups as defined above, Ar can independently represent aryl or heteroaryl groups as defined above, and X represents a halogen such as Br or I. This reaction can, for example, be completed under reflux for a suitable time, such as 48 h, in the presence of a suitable catalyst such as 4A molecular sieve (which is used to remove moisture, etc., from the reaction system) and a suitable base such as sodium tert-butoxide, in a suitable organic solvent such as o-xylene.

[0086] For example, in a particular embodiment, the palladium complex (L7-Pd-G6) and borane adduct (L7-BH3) of the present invention can be used together as a catalyst to promote the synthesis of triarylamine compounds, and the specific reaction scheme can be as follows:

[0087]

[0088] The following embodiments will help to further understand the present invention, but should not be construed as limiting the scope of the subject matter of the present invention to the following embodiments. All technologies implemented based on the above content of the present invention fall within the scope of the present invention.

[0089] General instructions:

[0090] The following examples use abbreviations, whose meanings are as follows: Me is methyl, t Bu is tert-butyl, Ph is phenyl, DMSO is dimethyl sulfoxide, THF is tetrahydrofuran, PE is petroleum ether, EA is ethyl acetate, DCM is dichloromethane, DABCO is triethylenediamine, NIS is N-iodosuccinimide, Et is ethyl, OAc is acetic acid, Cod is 1,5-cyclooctadiene, chloroform is chloroform, dichloromethane is dichloromethane, allyl is allyl, and cinnamyl is phenylacrylonitrile.

[0091] eq is equivalent, rt is room temperature, TLC is thin-layer chromatography, NMR is nuclear magnetic resonance, and HRMS is high-resolution mass spectrometry.

[0092] The solvents used were purified and / or dried using standard procedures before use; all reagents used were commercially available or synthesized according to existing literature methods and were purified before use.

[0093] Example 1: Preparation of substrate 7-bromo-2-phenylbicyclo[2,2,1]hept-2-ene (S1-Br)

[0094]

[0095] Norbornene (20 g, 212 mmol) and dichloromethane (200 mL) were added to a 500 mL single-necked round-bottom flask and stirred until completely dissolved. Pyridinium tribromide (81.5 g, 255 mmol) was rapidly added at -78°C, and the reaction mixture was stirred at this temperature for 1 hour, then heated to room temperature and stirred for another 8 hours. After confirming the reaction was complete by TLC, the reaction mixture was washed with saturated aqueous sodium bicarbonate solution (150 mL × 3 times) and aqueous sodium thiosulfate solution (150 mL × 3 times), and the organic phase was collected. The organic phase was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by vacuum distillation, and a colorless oily intermediate, 2,7-dibromobicyclo[2.2.1]heptane (29.6 g, 55% yield), was collected at 50°C and 1.5 Pa.

[0096] 1 H NMR (600 MHz, Chloroform-d) δ 3.98 – 3.95 (m, 2H), 2.69 – 2.64 (m,2H), 2.43 (s, 1H), 2.23 (dd, J = 14.0, 8.1 Hz, 1H), 1.73 – 1.63 (m, 2H), 1.36–1.26 (m, 2H).

[0097] 13 C NMR (151 MHz, Chloroform-d) δ 53.9, 50.4, 48.3, 44.6, 42.1, 28.5, 25.3.

[0098] Next, potassium tert-butoxide (35.4 g, 315 mmol) was added to a 500 mL two-necked round-bottom flask, and the atmosphere was replaced with argon. Then, 200 mL of anhydrous THF was added. 2,7-dibromobicyclo[2.2.1]heptane (20 g, 78.7 mmol) obtained above was added at 0°C, and the mixture was stirred at room temperature for 48 hours. After the reaction was complete, 200 mL of diethyl ether was added. The resulting mixture was washed with saturated brine (200 mL × 3 times), the organic phase was collected, dried over anhydrous magnesium sulfate, filtered, and carefully concentrated under reduced pressure to give the colorless oily target product S1-Br (13.0 g, 95% yield).

[0099] 1H NMR (600 MHz, Chloroform-d) δ 6.01 (s, 2H), 3.86 (s, 1H), 3.01 (s,2H), 1.76 – 1.75 (m, 2H), 1.11 – 1.08 (m, 2H).

[0100] 13 C NMR (151 MHz, Chloroform-d) δ 133.0, 66.2, 49.4, 22.7.

[0101] Example 2: Preparation of substrate 7-iodo-2-phenylbicyclo[2,2,1]hept-2-ene (S1-I)

[0102]

[0103] Lithium bromide (LiBr, 17.4 g, 200 mmol), N-iodosuccinimide (NIS, 24.8 g, 110 mmol), ethyl acetate (EA, 125 mL), and acetic acid (100 mL) were added to a 500 mL single-necked round-bottom flask. The mixture was stirred at room temperature until all solids were completely dissolved. Norbornene (9.41 g, 100 mmol) was then added, and the resulting mixture was stirred overnight at room temperature. The solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate and washed successively with aqueous sodium thiosulfate solution, saturated sodium bicarbonate solution, and aqueous sodium hydroxide solution. The organic phase was collected, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. Purification was performed by silica gel column chromatography (using petroleum ether (PE) as eluent) to give a colorless oily intermediate, 2-bromo-7-iodobicyclo[2.2.1]heptane (9.81 g, 33% yield).

[0104] 1 H NMR (600 MHz, Chloroform-d) δ 3.97 – 3.93 (m, 1H), 3.81 (s, 1H), 2.68 (d, J = 4.4 Hz, 1H), 2.64 – 2.60 (m, 1H), 2.42 (s, 1H), 2.21 (dd, J =14.0, 8.2 Hz, 1H), 1.72 – 1.60 (m, 2H), 1.27 – 1.23 (m, 2H).

[0105] 13 C NMR (151 MHz, Chloroform-d) δ 50.7, 49.2, 46.0, 43.0, 28.8, 27.2, 24.9.

[0106] Following the same procedure as above for preparing S1-Br from 2,7-dibromobicyclo[2.2.1]heptane, except that 2-bromo-7-iodobicyclo[2.2.1]heptane (9.39 g, 31.2 mmol) was used as the starting material, the target compound S1-I (5.66 g, 82% yield) was obtained as a colorless oil.

[0107] 1 H NMR (600 MHz, Chloroform-d) δ 6.01 (s, 2H), 3.76 (s, 1H), 3.04 (s,2H), 1.79 – 1.77 (m, 2H), 1.10 – 1.06 (m, 2H).

[0108] 13 C NMR (151 MHz, Chloroform-d) δ 134.7, 51.0, 45.9, 21.9.

[0109] Example 3: Preparation of intermediate S2

[0110] General synthesis scheme

[0111]

[0112] Pd(OAc)2 and the structure is The ligand L' (prepared according to the method in Org. Lett., 2004, 6, 4105-4107) was placed in a two-necked flask equipped with a reflux condenser. The system was protected by three displacements with argon, followed by the addition of dimethyl sulfoxide (DMSO). The mixture was stirred at approximately 60°C for 10 minutes. After cooling to room temperature, formic acid (HCOOH), triethylamine (Et3N), substrate S1 (where X is, for example, Br or I), and aryl halide AX' (where X' is, for example, I; purchased from Anhui Zesheng Technology Co., Ltd.) were added sequentially. The reaction mixture was stirred at approximately 120°C and monitored by thin-layer chromatography (TLC) until the reaction was complete. After the reaction was complete, water was added, and the mixture was extracted three times with dichloromethane (DCM). The organic phases were combined, dried over anhydrous magnesium sulfate (MgSO4), filtered, and concentrated under reduced pressure. Purification was performed by silica gel rapid column chromatography to give intermediate S2.

[0113] Based on the above general synthesis scheme, the following intermediate S2 was prepared:

[0114] Example 3-1: Preparation of intermediate S2-1

[0115] 7-Bromo-2-phenylbicyclo[2.2.1]heptane (S2-1) (where substrate S1 is S1-Br and aryl halide AX' is iodobenzene)

[0116]

[0117] Colorless oily liquid, yield 82%.

[0118] 1 H NMR (600 MHz, Chloroform-d) δ 7.36 (d, J = 7.8 Hz, 2H), 7.32 –7.29 (m, 2H), 7.18 (t, J = 7.3 Hz, 1H), 4.00 (s, 1H), 3.03 – 3.00 (m, 1H),2.95 (s, 1H), 2.53 – 2.49 (m, 2H), 2.08 – 2.05 (m, 1H), 1.78 – 1.76 (m, 2H), 1.54 – 1.48 (m, 2H).

[0119] 13 C NMR (151 MHz, Chloroform-d) δ 145.3, 127.9, 127.1, 125.4, 56.4, 46.4, 46.0, 43.8, 36.1, 30.1, 26.3.

[0120] HRMS(ESI) [M+Na] + Calculated value: 273.0249, Experimental value: 273.0237.

[0121] Example 3-2: Preparation of intermediate S2-4

[0122] 7-Bromo-2-(4-methoxyphenyl)bicyclo[2.2.1]heptane (S2-4) (where substrate S1 is S1-Br and aryl halide AX' is 4-iodoanisole)

[0123]

[0124] White solid, 73% yield, melting point 63 – 65 °C.

[0125] 1H NMR (600 MHz, Chloroform-d) δ 7.25 (d, J = 8.4 Hz, 2H), 6.84 (d, J= 8.4 Hz, 2H), 3.97 (s, 1H), 3.80 (s, 3H), 2.95 – 2.93 (m, 1H), 2.85 (s, 1H), 2.46 – 2.42 (m, 2H), 2.04 – 2.00 (m, 1H), 1.77 – 1.71 (m, 2H), 1.51 – 1.44(m, 2H).

[0126] 13 C NMR (151 MHz, Chloroform-d) δ 157.4, 137.3, 128.0, 113.3, 56.4, 55.3, 46.8, 45.4, 43.9, 36.2, 30.1, 26.3.

[0127] HRMS(ESI) [M+Na] + Calculated value: 303.0355, Experimental value: 303.0349.

[0128] Example 3-3: Preparation of intermediate S2-5

[0129] 7-Bromo-2-[4-(trifluoromethyl)phenyl]bicyclo[2.2.1]heptane (S2-5) (where substrate S1 is S1-Br and aryl halide AX' is 1-iodo-4-(trifluoromethyl)benzene)

[0130]

[0131] A colorless, oily liquid with a yield of 59%.

[0132] 1 H NMR (600 MHz, Chloroform-d) δ 7.53 (d, J = 8.2 Hz, 2H), 7.44 (d, J= 8.2 Hz, 2H), 3.99 (s, 1H), 3.02 – 3.00 (m, 1H), 2.94 (s, 1H), 2.49 – 2.45(m, 2H), 2.11 – 2.07 (m, 1H), 1.79 – 1.77 (m, 2H), 1.56 – 1.48 (m, 2H).

[0133] 13C NMR (151 MHz, Chloroform-d) δ 149.5, 127.7 (q, J = 32.1 Hz),127.3, 124.9 (q, J = 3.8 Hz), 124.5 (q, J = 271.3 Hz), 56.2, 46.4, 46.0,43.8, 36.1, 30.0, 26.2.

[0134] 19 F NMR (565 MHz, Chloroform-d) δ -62.02.

[0135] HRMS(ESI) [MH] - Calculated value: 317.0158, Experimental value: 317.0161.

[0136] Examples 3-4: Preparation of intermediate S2-6

[0137] 1-(7-bromobicyclo[2.2.1]heptane-2-yl)naphthalene(S2-6) (where substrate S1 is S1-Br and aryl halide AX' is 1-iodonaphthalene)

[0138]

[0139] White solid, yield 56%, melting point 105°C-107°C.

[0140] 1 H NMR (600 MHz, Chloroform-d) δ 8.03 (d, J = 8.6 Hz, 1H), 7.90 (d, J= 8.6 Hz, 1H), 7.75 (dd, J = 11.3, 7.7 Hz, 2H), 7.56 – 7.53 (m, 1H), 7.52 –7.46 (m, 2H), 4.06 (s, 1H), 3.56 (t, J = 8.3 Hz, 1H), 2.93 (s, 1H), 2.67 –2.63 (m, 1H), 2.57 (s, 1H), 2.19 (dd, J = 12.4, 9.1 Hz, 1H), 1.90 – 1.80 (m,2H), 1.75 – 1.71 (m, 1H), 1.70 – 1.65 (m, 1H).

[0141] 13C NMR (151 MHz, Chloroform-d) δ 139.4, 134.0, 132.2, 129.1, 126.7,125.7, 125.2, 125.0, 124.8, 124.3, 56.5, 47.0, 43.8, 43.7, 36.2, 30.6, 26.1.

[0142] Examples 3-5: Preparation of intermediate S2-7

[0143] 2-(3,5-di-tert-butylphenyl)-7-iodobicyclo[2.2.1]heptane (S2-7) (where substrate S1 is S1-I and aryl halide AX' is 3,5-di-tert-butyl-1-iodobenzene)

[0144]

[0145] White solid, yield 83%, melting point 59°C-61°C.

[0146] 1 H NMR (600 MHz, Chloroform-d) δ 7.21 (s, 3H), 3.86 (s, 1H), 3.01 – 2.96 (m, 2H), 2.49 – 2.45 (m, 2H), 2.09 – 2.05 (m, 1H), 1.81 – 1.72 (m, 2H), 1.54 – 1.50 (m, 1H), 1.41 – 1.38 (m, 1H), 1.35 (s, 18H).

[0147] 13 C NMR (151 MHz, Chloroform-d) δ 149.8, 143.6, 122.0, 119.2, 47.0, 46.7, 45.3, 37.6, 35.0, 31.7, 31.1, 31.0, 25.9.

[0148] HRMS(ESI) [M+Na] + Calculated value: 433.1363, Experimental value: 433.1353.

[0149] Examples 3-6: Preparation of intermediate S2-8

[0150] 2-(3,5-Dimethoxyphenyl)-7-iodobicyclo[2.2.1]heptane (S2-8) (where substrate S1 is S1-I and aryl halide AX' is 1,3-dimethoxy-5-iodophenyl)

[0151]

[0152] Bright yellow solid, yield 71%, melting point 76 – 78°C.

[0153] 1 H NMR (600 MHz, Chloroform-d) δ 6.50 (s, 2H), 6.29 (s, 1H), 3.83 (s,1H), 3.80 (s, 6H), 2.93 – 2.87 (m, 2H), 2.48 – 2.44 (m, 2H), 2.04 – 2.00 (m,1H), 1.79 – 1.71 (m, 2H), 1.51 – 1.47 (m, 1H), 1.38 – 1.35 (m, 1H).

[0154] 13 C NMR (151 MHz, Chloroform-d) δ 160.4, 147.7, 105.7, 97.2, 55.4, 47.0, 46.3, 45.1, 37.2, 31.0, 30.7, 25.9.

[0155] HRMS (APCI) [M+H] + Calculated value: 359.0502, Experimental value: 359.0491.

[0156] Example 4: Preparation of ligand L

[0157] General synthesis scheme

[0158]

[0159] Among them, X, Ar and R 1 and R 2 As defined above.

[0160] Add intermediate compound S2 to a dry, double-necked flask. Purge the flask with argon gas and add dry tetrahydrofuran (THF, 0.2 M). Stir the mixture at –78 °C, then add dropwise a solution of tert-butyllithium (1.3 M n-pentane solution, 2.5 equivalents for the starting material S1-Br; n-butyllithium is used instead of S1-I). Continue stirring at –78 °C for 1 hour, then add R dropwise. 1 R 2 PCl (3 equivalents; reagent purchased from Anhui Zesheng Technology Co., Ltd.). Slowly heat the reaction system to room temperature and stir overnight.

[0161] The mixture was then cooled to 0 °C, and BH3-THF solution (1.0 M, 3 equivalents; reagent purchased from Anhui Zesheng Technology Co., Ltd.) was added dropwise. The resulting mixture was heated to room temperature and stirred for 3 hours. After the reaction was complete, it was carefully quenched with water. The solvent was removed under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether (PE) / ethyl acetate (EA) = 20:1, v / v). The obtained solid was recrystallized from the petroleum ether / ethyl acetate system to finally obtain the product L-BH3.

[0162] In a separate dry, double-necked flask, L-BH3 and 1,4-diazabicyclo[2.2.2]octane (DABCO, 3.0 equivalents; reagent purchased from Anhui Zesheng Technology Co., Ltd.) were added. The flask was purged with argon gas, and dry tetrahydrofuran (0.1 M) was added. The reaction mixture was heated and stirred at 60 °C for 12 hours. After confirming the completion of the reaction by thin-layer chromatography (TLC), the solvent was removed under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 100:1, v / v) to give the final product L.

[0163] Based on the above general synthetic scheme, the following ligand compound L was prepared:

[0164] Example 4-1: Preparation of ligand L1-BH3

[0165] Dicyclohexyl(2-phenylbicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L1-BH3) (wherein the intermediate used is S2-1, and R 1 and R 2 All are cyclohexyl (Cy)

[0166]

[0167] White solid, 48% yield, melting point 187 – 189°C.

[0168] 11H NMR (600 MHz, Chloroform-d) δ 7.39 (d, J = 7.7 Hz, 2H), 7.32 – 7.29 (m, 2H), 7.16 (t, J = 7.3 Hz, 1H), 2.96 – 2.93 (m, 1H), 2.81 (s, 1H), 2.75 – 2.71 (m, 1H), 2.64 (s, 1H), 1.79 – 1.44 (m, 19H), 1.26 – 1.11 (m, 4H), 1.05 – 0.88 (m, 4H), 0.55 – 0.07 (m, 4H).

[0169] 13 13C NMR (151 MHz, Chloroform-d) δ 143.2, 128.13, 128.09, 126.0, 47.7 (d, J = 1.9 Hz), 46.1, 45.5 (d, J = 29.8 Hz), 41.6 (d, J = 2.7 Hz), 35.9 (d, J = 33.6 Hz), 34.4, 34.2 (d, J = 10.6 Hz), 33.4 (d, J = 30.3 Hz), 29.0 (d, J = 11.0 Hz), 28.0 (d, J = 6.4 Hz), 27.20, 27.17 (d, J = 5.5 Hz), 27.08 (d, J = 15.1 Hz), 26.9 (d, J = 1.4 Hz), 26.8, 26.7 (d, J = 10.5 Hz), 26.6, 26.2 (d, J = 1.5 Hz), 26.0 (d, J = 1.4 Hz).

[0170] 31 31P NMR (243 MHz, Chloroform-d) δ 19.79 (d, J = 69.3 Hz).

[0171] 11 11B NMR (193 MHz, Chloroform-d) δ -43.40 (d, J = 52.6 Hz).

[0172] HRMS(ESI) [M+Na] + Calculated: 405.2853, Found: 405.2848.

[0173] Example 4-2: Preparation of ligand L1

[0174] Dicyclohexyl(2-phenylbicyclo[2.2.1]heptane-7-yl)phosphine (L1) (wherein the intermediate used is S2-1, and R 1 and R 2 All are cyclohexyl (Cy)

[0175]

[0176] White solid, 99% yield, melting point 57–59°C.

[0177] 1 H NMR (600 MHz, Chloroform-d) δ 7.38 (d, J = 7.7 Hz, 2H), 7.27 –7.24 (m, 2H), 7.11 (t, J = 7.3 Hz, 1H), 2.84 – 2.81 (m, 1H), 2.68 – 2.64 (m,1H), 2.55 (d, J = 3.5 Hz, 1H), 2.36 (s, 1H), 1.77 – 1.60 (m, 10H), 1.55 –1.40 (m, 6H), 1.26 – 1.15 (m, 6H), 1.05 – 0.98 (m, 4H), 0.77 – 0.72 (m, 2H).

[0178] 13C NMR (151 MHz, Chloroform-d) δ 144.6, 128.0 (d, J = 3.8 Hz), 127.9,125.4, 48.7 (d, J = 3.4 Hz), 47.1 (d, J = 20.1 Hz), 47.0, 42.5 (d, J = 15.2Hz), 35.5 (d, J = 14.0 Hz), 34.4 (d, J = 14.8 Hz), 33.9 (d, J = 9.7 Hz), 33.4(d, J = 5.4 Hz), 32.2 (d, J = 18.0 Hz), 31.4 (d, J = 15.8 Hz), 30.3 (d, J =11.6 Hz), 29.5 (d, J = 5.7 Hz), 28.4 (d, J = 1.4 Hz), 28.1 (d, J = 13.3 Hz), 27.9 (d, J = 4.4 Hz), 27.6 (d, J = 8.6 Hz), 27.3 (d, J = 10.6 Hz), 26.7 (d, J= 1.1 Hz), 26.6 (d, J = 1.2 Hz).

[0179] 31 P NMR (243 MHz, Chloroform-d) δ -10.16.

[0180] HRMS (ESI) [M+H] + Calculated value: 369.2706, Experimental value: 369.2700.

[0181] Example 4-3: Preparation of ligand L2

[0182] Diphenyl(2-phenylbicyclo[2.2.1]heptane-7-yl)phosphine (L2) (wherein the intermediate used is S2-1, and R 1 and R 2 All are phenyl (Ph)

[0183]

[0184] L2 can be purified without BH3 protection.

[0185] White solid, 57% yield, melting point 62 – 64 °C.

[0186] 1H NMR (600 MHz, Chloroform-d) δ 7.25 – 7.22 (m, 2H), 7.20 – 7.11 (m,10H), 7.08 (t, J = 6.9 Hz, 1H), 7.01 (t, J = 7.1 Hz, 2H), 2.83 – 2.81 (m,1H), 2.63 – 2.59 (m, 1H), 2.55 (s, 1H), 2.33 (s, 1H), 2.27 (d, J = 6.3 Hz,1H), 1.89 – 1.85 (m, 1H), 1.70 – 1.65 (m, 2H), 1.48 – 1.40 (m, 2H).

[0187] 13 C NMR (151 MHz, Chloroform-d) δ 145.3 (d, J = 1.4 Hz), 133.8 (d, J =19.5 Hz), 132.4 (d, J = 18.8 Hz), 128.5, 128.30, 128.26, 128.20, 128.15,128.06, 127.9, 127.5 (d, J = 3.6 Hz), 125.4, 50.8 (d, J = 15.4 Hz), 46.4 (d,J = 1.4 Hz), 45.5 (d, J = 7.9 Hz), 41.3 (d, J = 13.8 Hz), 36.1 (d, J = 9.2Hz), 33.1 (d, J = 8.0 Hz), 29.8 (d, J = 5.8 Hz).

[0188] 31 P NMR (243 MHz, Chloroform-d) δ -21.53.

[0189] HRMS (ESI) [M+H] + Calculated value: 357.1767, Experimental value: 357.1762.

[0190] Example 4-4: Preparation of ligand L3-BH3

[0191] Diisopropyl(2-phenylbicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L3-BH3) (wherein the intermediate used is S2-1, and R 1 and R 2 All are isopropyl ( i Pr))

[0192]

[0193] White solid, yield 36%, melting point 145 – 147 °C.

[0194] 1 H NMR (600 MHz, Chloroform-d) δ 7.35 (d, J = 8.0 Hz, 2H), 7.30 –7.27 (m, 2H), 7.14 (t, J = 7.3 Hz, 1H), 2.95 – 2.92 (m, 1H), 2.87 (s, 1H),2.77 – 2.73 (m, 1H), 2.69 (s, 1H), 1.88 – 1.80 (m, 1H), 1.79 – 1.70 (m, 3H), 1.67 – 1.61 (m, 2H), 1.50 – 1.46 (m, 1H), 1.30 – 1.23 (m, 1H), 1.13 – 1.09(m, 6H), 1.00 – 0.97 (m, 3H), 0.83 – 0.79 (m, 3H), 0.52 – 0.07 (m, 3H).

[0195] 13 C NMR (151 MHz, Chloroform-d) δ 142.9, 128.0, 127.8, 125.9, 47.2,46.0, 45.4 (d, J = 29.6 Hz), 41.6, 34.7, 34.2 (d, J = 10.9 Hz), 29.1 (d, J =10.8 Hz), 25.3 (d, J = 34.2 Hz), 23.4 (d, J = 30.9 Hz), 18.3, 17.9, 17.7,16.8 (d, J = 5.3 Hz).

[0196] 31 P NMR (243 MHz, Chloroform-d) δ 27.16 (d, J = 72.8 Hz).

[0197] 11 B NMR (193 MHz, Chloroform-d) δ -43.72 (d, J = 58.7 Hz).

[0198] HRMS(ESI) [M+Na]+ Calculated value: 325.2227, Experimental value: 325.2221.

[0199] Examples 4-5: Preparation of ligand L3

[0200] Diisopropyl(2-phenylbicyclo[2.2.1]heptane-7-yl)phosphine (L3) (wherein the intermediate used is S2-1, and R 1 and R 2 All are isopropyl ( i Pr))

[0201]

[0202] A colorless, oily liquid with a yield of 93%.

[0203] 1 H NMR (600 MHz, Chloroform-d) δ 7.37 (d, J = 7.8 Hz, 2H), 7.26 –7.23 (m, 2H), 7.11 (t, J = 7.2 Hz, 1H), 2.82 – 2.80 (m, 1H), 2.64 – 2.59 (m,2H), 2.43 – 2.32 (m, 1H), 1.72 – 1.57 (m, 6H), 1.15 (sept, J = 7.4 Hz, 2H), 1.07 – 1.00 (m, 6H), 0.88 – 0.86 (m, 3H), 0.79 – 0.75 (m, 3H).

[0204] 13 C NMR (151 MHz, Chloroform-d) δ 144.7, 128.1, 127.9, 125.4, 48.3 (d,J = 4.4 Hz), 48.0 (d, J = 21.4 Hz), 47.0, 42.1 (d, J = 13.3 Hz), 34.4 (d, J =9.1 Hz), 33.4 (d, J = 5.8 Hz), 29.5 (d, J = 5.4 Hz), 24.7 (d, J = 14.4 Hz), 23.7 (d, J = 14.6 Hz), 21.4 (d, J = 9.4 Hz), 21.3 (d, J = 8.4 Hz), 20.6 (d, J= 13.4 Hz), 18.1 (d, J = 3.6 Hz).

[0205] 31 P NMR (243 MHz, Chloroform-d) δ -3.83.

[0206] HRMS (ESI) [M+H] + Calculated value: 289.2080, Experimental value: 289.2071.

[0207] Examples 4-6: Preparation of ligand L4-BH3

[0208] Dicyclohexyl(2-(4-methoxyphenyl)bicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L4-BH3) (wherein the intermediate used is S2-4, and R 1 and R 2 All are cyclohexyl (Cy)

[0209]

[0210] White solid, 41% yield, melting point 180 – 182 °C.

[0211] 1 H NMR (400 MHz, Chloroform-d) δ 7.30 (d, J = 8.6 Hz, 2H), 6.85 (d, J= 8.6 Hz, 2H), 3.77 (s, 3H), 2.90 – 2.86 (m, 1H), 2.73 – 2.62 (m, 3H), 1.79 – 1.41 (m, 20H), 1.26 – 1.12 (m, 4H), 1.03 – 0.86 (m, 4H), 0.60 – 0.06 (m, 3H).

[0212] 13C NMR (101 MHz, Chloroform-d) δ 157.9, 135.2, 129.1, 113.5, 55.4,48.1, 45.5 (d, J = 29.8 Hz), 45.4, 41.7 (d, J = 2.8 Hz), 36.0 (d, J = 33.6Hz), 34.1 (d, J = 10.8 Hz), 33.3 (d, J = 30.2 Hz), 29.0 (d, J = 11.0 Hz), 28.1, 27.9, 27.2 (d, J = 7.2 Hz), 27.08, 27.07, 26.98 (d, J = 7.3 Hz), 26.90,26.86, 26.7 (d, J = 10.5 Hz), 26.5, 26.1 (d, J = 23.9 Hz).

[0213] 31 P NMR (162 MHz, Chloroform-d) δ 19.64 (d, J = 76.0 Hz).

[0214] 11 B NMR (128 MHz, Chloroform-d) δ -43.40 (d, J = 59.4 Hz).

[0215] HRMS(ESI) [M+Na] + Calculated value: 435.2959, Experimental value: 435.2954.

[0216] Examples 4-7: Preparation of ligand L4

[0217] Dicyclohexyl(2-(4-methoxyphenyl)bicyclo[2.2.1]heptane-7-yl)phosphine (L4) (wherein the intermediate used is S2-4, and R 1 and R 2 All are cyclohexyl (Cy)

[0218]

[0219] White solid, 41% yield, melting point 80 – 81 °C.

[0220] 1H NMR (400 MHz, Chloroform-d) δ 7.29 (d, J = 7.7 Hz, 2H), 6.81 (d, J= 7.7 Hz, 2H), 3.77 (s, 3H), 2.79 – 2.75 (m, 1H), 2.62 – 2.58 (m, 1H), 2.47(s, 1H), 2.34 (s, 1H), 1.75 – 1.61 (m, 10H), 1.53 – 1.40 (m, 6H), 1.27 – 1.19(m, 6H), 1.07 – 0.98 (m, 4H), 0.81 – 0.68 (m, 2H).

[0221] 13 C NMR (101 MHz, Chloroform-d) δ 157.4, 136.7, 129.0, 113.3, 55.4,48.9 (d, J = 2.5 Hz), 47.0 (d, J = 19.9 Hz), 46.3, 42.6 (d, J = 15.5 Hz), 35.5 (d, J = 13.7 Hz), 34.4 (d, J = 14.6 Hz), 34.0 (d, J = 9.5 Hz), 33.3 (d,J = 5.2 Hz), 32.5 (d, J = 18.3 Hz), 31.4 (d, J = 15.9 Hz), 30.2 (d, J = 11.7Hz), 29.53, 29.47, 28.3, 28.02 (d, J = 17.4 Hz), 28.97, 27.5 (d, J = 8.6 Hz), 27.3 (d, J = 10.6 Hz), 26.6 (d, J = 6.9 Hz).

[0222] 31 P NMR (162 MHz, Chloroform-d) δ -10.00.

[0223] HRMS (ESI) [M+H] + Calculated value: 399.2811, Experimental value: 399.2804.

[0224] Examples 4-8: Preparation of ligand L5-BH3

[0225] Dicyclohexyl(2-(4-(trifluoromethyl)phenyl)bicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L5-BH3) (wherein the intermediate used is S2-5, and R 1 and R 2 All are cyclohexyl (Cy)

[0226]

[0227] White solid, 51% yield, melting point 180 – 183 °C.

[0228] 1 H NMR (600 MHz, Chloroform-d) δ 7.57 (d, J = 8.2 Hz, 2H), 7.51 (d, J= 8.2 Hz, 2H), 2.98 – 2.95 (m, 1H), 2.81 (s, 1H), 2.78 – 2.74 (m, 1H), 2.66(s, 1H), 1.80 – 1.46 (m, 20H), 1.26 – 1.10 (m, 4H), 1.05 – 0.93 (m, 3H), 0.85 – 0.79 (m, 1H), 0.49 – 0.22 (m, 3H).

[0229] 13 C NMR (151 MHz, Chloroform-d) δ 147.4, 128.5, 128.4 (q, J = 32.2Hz), 125.0 (q, J = 3.9 Hz), 124.5 (q, J = 271.5 Hz), 47.7, 46.2, 45.4 (d, J =29.3 Hz), 41.7 (d, J = 2.8 Hz), 35.9 (d, J = 33.6 Hz), 34.3, 34.2 (d, J =10.5 Hz), 33.8 (d, J = 30.3 Hz), 29.0 (d, J = 10.8 Hz), 28.0, 27.9, 27.2 (d,J = 6.7 Hz), 27.1, 27.0 (d, J = 7.2 Hz), 26.9, 26.7 (d, J = 10.7 Hz), 26.6, 26.1, 26.0.

[0230] 31P NMR (243 MHz, Chloroform-d) δ 19.69 (d, J = 74.4 Hz).

[0231] 19 F NMR (565 MHz, Chloroform-d) δ -62.28.

[0232] 11 B NMR (128 MHz, Chloroform-d) δ -43.33 (d, J = 58.0 Hz).

[0233] HRMS(ESI) [M+Na] + Calculated value: 473.2727, Experimental value: 437.2721.

[0234] Examples 4-9: Preparation of ligand L5

[0235] Dicyclohexyl(2-(4-(trifluoromethyl)phenyl)bicyclo[2.2.1]heptane-7-yl)phosphine (L5) (wherein the intermediate used is S2-5, and R 1 and R 2 All are cyclohexyl (Cy)

[0236]

[0237] A colorless, oily liquid with a yield of 96%.

[0238] 1 H NMR (600 MHz, Chloroform-d) δ 7.50 (s, 4H), 2.87 – 2.84 (m, 1H), 2.69 – 2.63 (m, 1H), 2.56 – 2.55 (m, 1H), 2.40 – 2.38 (m, 1H), 1.77 – 1.65(m, 12H), 1.57 – 1.44 (m, 6H), 1.24 – 1.16 (m, 4H), 1.03 – 0.98 (m, 4H), 0.76 – 0.70 (m, 2H).

[0239] 13C NMR (151 MHz, Chloroform-d) δ 149.0, 128.4 (d, J = 4.2 Hz), 127.7(q, J = 271.9 Hz), 124.7 (q, J =10.3 Hz), 124.7, 48.8 (d, J = 4.1 Hz), 47.1,47.0 (d, J = 20.4 Hz), 42.4 (d, J = 14.4 Hz), 35.3 (d, J = 14.0 Hz), 34.6 (d,J = 14.8 Hz), 33.9 (d, J = 9.5 Hz), 33.3 (d, J = 5.3 Hz), 32.1 (d, J = 17.4Hz), 31.4 (d, J = 15.7 Hz), 30.3 (d, J = 11.3 Hz), 29.5 (d, J = 5.4 Hz), 28.6, 28.04, 27.95, 27.93, 27.6 (d, J = 8.6 Hz), 27.3 (d, J = 10.7 Hz), 26.6.

[0240] 31 P NMR (243 MHz, Chloroform-d) δ -10.68.

[0241] 19 F NMR (565 MHz, Chloroform-d) δ -62.14.

[0242] HRMS (ESI) [M+H] + Calculated value: 437.2580, Experimental value: 437.2570.

[0243] Examples 4-10: Preparation of ligand L6-BH3

[0244] Dicyclohexyl(2-(naphth-1-yl)bicyclo[2.2.1]heptane-7-yl)phosphoborane adduct (L6-BH3) (wherein the intermediate used is S2-6, and R 1 and R 2 All are cyclohexyl (Cy)

[0245]

[0246] White solid, 58% yield, melting point 232 – 234 °C.

[0247] 1H NMR (600 MHz, Chloroform-d) δ 7.94 (d, J = 8.4 Hz, 1H), 7.86 (d, J= 8.0 Hz, 1H), 7.80 (d, J = 7.4 Hz, 1H), 7.71 (d, J = 8.0 Hz, 1H), 7.54 –7.51 (m, 1H), 7.49 – 7.45 (m, 2H), 3.45 – 3.42 (m, 1H), 3.04 – 3.00 (m, 1H),2.81 (s, 1H), 2.74 (s, 1H), 1.99 – 1.96 (m, 1H), 1.87 – 1.74 (m, 4H), 1.71 –1.69 (m, 1H), 1.65 – 1.45 (m, 10H), 1.34 – 1.07 (m, 8H), 0.91 – 0.70 (m, 4H),0.30 – 0.24 (m, 1H), 0.08 – 0.01 (m, 1H), -0.27 – -0.33 (m, 1H)。

[0248] 13 C NMR (151 MHz, Chloroform-d) δ 138.1, 134.4, 132.5, 129.0, 127.2,125.6, 125.4, 125.3, 125.2, 124.8, 48.4 (d, J = 2.3 Hz), 45.7 (d, J = 30.0Hz), 44.1, 41.5 (d, J = 3.2 Hz), 36.6 (d, J = 34.3 Hz), 34.2 (d, J = 10.6Hz), 33.5, 33.3, 28.8 (d, J = 10.9 Hz), 27.74, 27.66, 27.2 (d, J = 10.8 Hz),26.9 (d, J = 6.0 Hz), 26.7 (d, J = 12.6 Hz), 26.6 (d, J = 10.8 Hz), 26.25 (d,J = 8.6 Hz), 26.16, 26.0 (d, J = 1.4 Hz), 25.9 (d, J = 1.4 Hz)。

[0249] 31 P NMR (243 MHz, Chloroform-d) δ 18.93 (d, J = 76.5 Hz)。

[0250] 11 B NMR (193 MHz, Chloroform-d) δ -43.26 (d, J = 58.1 Hz).

[0251] HRMS(ESI) [M+Na] + Calculated value: 455.3009, Experimental value: 455.3004.

[0252] Examples 4-11: Preparation of ligand L6

[0253] Dicyclohexyl(2-(naphth-1-yl)bicyclo[2.2.1]heptane-7-yl)phosphine (L6) (wherein the intermediate used is S2-6, and R 1 and R 2 All are cyclohexyl (Cy)

[0254]

[0255] White solid, 99% yield, melting point 156 – 158 °C.

[0256] 1 H NMR (600 MHz, Chloroform-d) δ 7.99 (d, J = 8.5 Hz, 1H), 7.84 (d, J= 8.1 Hz, 1H), 7.75 (d, J = 7.2 Hz, 1H), 7.67 (d, J = 8.1 Hz, 1H), 7.53 –7.50 (m, 1H), 7.47 – 7.45 (m, 1H), 7.42 – 7.40 (m, 1H), 3.39 – 3.37 (m, 1H), 2.99 – 2.95 (m, 1H), 2.57 (s, 1H), 2.43 (s, 1H), 1.85 – 1.65 (m, 9H), 1.39 –1.18 (m, 12H), 0.93 – 0.87 (m, 1H), 0.83 – 0.76 (m, 2H), 0.36 – 0.29 (m, 1H), 0.21 – 0.11 (m, 3H).

[0257] 13C NMR (151 MHz, Chloroform-d) δ 139.2, 134.2, 132.8, 128.9, 126.6,125.5, 125.2, 125.1, 124.6, 124.4, 48.7 (d, J = 1.6 Hz), 47.5 (d, J = 19.9Hz), 44.0, 42.8 (d, J = 17.0 Hz), 35.9 (d, J = 13.1 Hz), 34.4 (d, J = 14.8Hz), 33.31 (d, J = 15.5 Hz), 33.29, 32.1 (d, J = 18.3 Hz), 31.4 (d, J = 15.8Hz), 30.3 (d, J = 12.9 Hz), 29.5 (d, J = 6.1 Hz), 27.9, 27.8 (d, J = 13.7Hz), 27.7 (d, J = 3.9 Hz), 27.4 (d, J = 9.1 Hz), 27.1 (d, J = 10.5 Hz), 26.6 (d, J = 1.1 Hz), 26.5 (d, J = 0.8 Hz).

[0258] 31 P NMR (243 MHz, Chloroform-d) δ -10.04.

[0259] HRMS (ESI) [M+H] + Calculated value: 419.2862, Experimental value: 419.2856.

[0260] Examples 4-12: Preparation of ligand L7-BH3

[0261] Dicyclohexyl(2-(3,5-di-tert-butylphenyl)bicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L7-BH3) (wherein the intermediate used is S2-7, and R 1 and R 2 All are cyclohexyl (Cy)

[0262]

[0263] White solid, 40% yield, melting point 128 – 131 °C.

[0264] 1H NMR (400 MHz, Chloroform-d) δ 7.27 (s, 1H), 7.20 (s, 2H), 2.97 – 2.93 (m, 1H), 2.77 – 2.74 (m, 2H), 2.65 (s, 1H), 1.78 – 1.43 (m, 18H), 1.34 (s, 18H), 1.26 – 0.78 (m, 10H), 0.62 – 0.15 (m, 3H).

[0265] 13 C NMR (101 MHz, Chloroform-d) δ 150.4, 142.2, 121.9, 120.8, 48.6,46.8, 45.6 (d, J = 30.4 Hz), 41.5, 35.7 (d, J = 33.5 Hz), 35.1, 34.7 (d, J =10.7 Hz), 34.1, 33.2 (d, J = 30.3 Hz), 31.7, 29.0 (d, J = 10.6 Hz), 28.0,27.32, 27.26, 27.13, 27.03, 26.9, 26.73 (d, J = 7.6 Hz), 26.66, 26.61, 26.0.

[0266] 31 P NMR (243 MHz, Chloroform-d) δ 19.78 (d, J = 56.7 Hz).

[0267] 11 B NMR (128 MHz, Chloroform-d) δ -43.52.

[0268] HRMS(ESI) [M+Na] + Calculated value: 517.4105, Experimental value: 517.4099.

[0269] Examples 4-13: Preparation of ligand L7

[0270] Dicyclohexyl(2-(3,5-di-tert-butylphenyl)bicyclo[2.2.1]heptane-7-yl)phosphine (L7) (wherein the intermediate used is S2-7, and R 1 and R 2 All are cyclohexyl (Cy)

[0271]

[0272] White solid, 91% yield, melting point 118 – 121 °C.

[0273] 1 H NMR (600 MHz, Chloroform-d) δ 7.21 (s, 2H), 7.19 (s, 1H), 2.84 –2.81 (m, 1H), 2.75 – 2.71 (m, 1H), 2.48 – 2.47 (m, 1H), 2.33 – 2.31 (m, 1H),1.76 – 1.55 (m, 10H), 1.49 – 1.38 (m, 6H), 1.33 (s, 18H), 1.25 – 1.16 (m,6H), 1.01 – 0.92 (m, 4H), 0.68 – 0.61 (m, 2H).

[0274] 13 C NMR (151 MHz, Chloroform-d) δ 149.7, 143.3, 122.5 (d, J = 4.0 Hz), 119.6, 49.8 (d, J = 3.1 Hz), 47.6, 46.9 (d, J = 21.1 Hz), 42.6 (d, J = 15.9Hz), 35.3 (d, J = 15.3 Hz), 35.0, 34.5 (d, J = 16.0 Hz), 33.9 (d, J = 5.3Hz), 33.3 (d, J = 10.4 Hz), 32.1 (d, J = 17.0 Hz), 31.8, 31.6 (d, J = 16.6Hz), 30.3 (d, J = 11.6 Hz), 29.4 (d, J = 5.6 Hz), 28.6, 27.9, 27.83, 27.80,27.6 (d, J = 8.4 Hz), 27.4 (d, J = 10.8 Hz), 26.7 (d, J = 9.5 Hz).

[0275] 31 P (243 MHz, Chloroform-d) δ -10.53.

[0276] HRMS (ESI) [M+H] + Calculated value: 481.3958, Experimental value: 481.3948.

[0277] Examples 4-14: Preparation of ligand L8-BH3

[0278] Dicyclohexyl(2-(3,5-dimethoxyphenyl)bicyclo[2.2.1]heptane-7-yl)phosphorboane adduct (L8-BH3) (wherein the intermediate used is S2-8, and R 1 and R 2 All are cyclohexyl (Cy)

[0279]

[0280] White solid, yield 36%, melting point 133 – 136 °C.

[0281] 1 H NMR (400 MHz, Chloroform-d) δ 6.55 (s, 2H), 6.29 (s, 1H), 3.81 (s,6H), 2.91 – 2.87 (m, 1H), 2.78 (s, 1H), 2.68 – 2.63 (m, 2H), 1.79 – 1.43 (m,20H), 1.27 – 0.95 (m, 8H), 0.74 – 0.26 (m, 3H).

[0282] 13 C NMR (101 MHz, Chloroform-d) δ 160.7, 146.0, 106.2, 98.6, 55.6,50.5, 48.0, 46.5, 45.6 (d, J = 29.4 Hz), 42.1, 41.6, 35.8 (d, J = 33.6 Hz),34.5, 34.2 (d, J = 10.7 Hz), 33.3 (d, J = 30.0 Hz), 28.9 (d, J = 10.8 Hz),28.5, 28.0 (d, J = 11.2 Hz), 27.3, 27.2 (d, J = 10.2 Hz), 27.0, 26.8 (d, J =9.6 Hz), 26.7, 26.1 (d, J = 24.6 Hz).

[0283] 31 P NMR (162 MHz, Chloroform-d) δ 19.81 (d, J = 57.0 Hz).

[0284] 11B NMR (128 MHz, Chloroform-d) δ -43.34.

[0285] HRMS(ESI) [M+Na] + Calculated value: 465.3064, Experimental value: 465.3058.

[0286] Examples 4-15: Preparation of ligand L8

[0287] Dicyclohexyl(2-(3,5-dimethoxyphenyl)bicyclo[2.2.1]heptane-7-yl)phosphine (L8) (wherein the intermediate used is S2-8, and R 1 and R 2 All are cyclohexyl (Cy)

[0288]

[0289] White solid, 79% yield, melting point 68 – 70 °C.

[0290] 1 H NMR (600 MHz, Chloroform-d) δ 6.57 (s, 2H), 6.24 (s, 1H), 3.78 (s,6H), 2.76 – 2.73 (m, 1H), 2.57 – 2.53 (m, 2H), 2.34 (s, 1H), 1.75 – 1.49 (m,14H), 1.44 – 1.37 (m, 3H), 1.26 – 1.17 (m, 5H), 1.11 – 1.00 (m, 4H), 0.91 –0.83 (m, 2H).

[0291] 13C NMR (151 MHz, Chloroform-d) δ 160.4, 147.5, 106.4, 97.6, 55.4,48.3, 47.3, 46.9 (d, J = 21.0 Hz), 42.3 (d, J = 14.8 Hz), 35.4 (d, J = 14.9Hz), 34.7, 34.6, 34.5, 33.4 (d, J = 5.4 Hz), 32.2 (d, J = 17.9 Hz), 31.4 (d,J = 15.9 Hz), 30.2 (d, J = 11.5 Hz), 29.4 (d, J = 5.4 Hz), 28.7, 28.1 (d, J =13.0 Hz), 28.0 (d, J = 4.7 Hz), 27.6 (d, J = 8.4 Hz), 27.4 (d, J = 10.5 Hz), 26.7 (d, J = 11.8 Hz).

[0292] 31 P NMR (243 MHz, Chloroform-d) δ -10.4.

[0293] HRMS (ESI) [M+H] + Calculated value: 429.2917, Experimental value: 429.2904.

[0294] Example 5: Preparation of palladium complex L7-Pd-G6

[0295]

[0296] In an argon-atmospheric glove box, ligand L7 (82.0 mg, 0.17 mmol), precursor S3 (59.3 mg, 1.0 equivalence; prepared according to the method of Ryan R. King et al.), 2-(trimethylsilyl)ethyl-4-bromobenzoate (54.0 mg, 1.05 equivalence; purchased from Anhui Zesheng Technology Co., Ltd.), and 2 mL of dry n-hexane (Hex) were added to the sample vial. After sealing the vial, it was removed from the glove box and heated at 60 °C for 12 hours. The reaction mixture was purified by silica gel column chromatography, eluting with a gradient of petroleum ether / ethyl acetate (50:1 → 10:1) to give the target product L7-Pd-G6 (yellow solid, 145 mg, yield 96%, melting point 129–131 °C).

[0297] 1H NMR (600 MHz, Dichloromethane-d2) δ 7.50 – 7.41 (m, 3H), 7.26 –7.22 (m, 1H), 7.10 – 7.02 (m, 3H), 4.30 (brs, 2H), 2.96 (brs, 1H), 2.86 (brs,1H), 1.94 – 0.86 (m, 50H), 0.05 (s, 9H).

[0298] 13 C NMR (151 MHz, Dichloromethane-d2) δ 167.9, 161.5, 151.3, 143.8,136.7, 128.1, 127.1, 125.8, 121.1, 63.0, 47.0, 38.5, 35.3, 33.1, 32.5, 31.9,31.8, 31.3, 30.2, 29.9, 29.5, 28.0, 27.2, 27.0, 26.6, 26.2, 23.3, 21.6, 19.7,17.8, 17.7, 14.5, -1.2.

[0299] 31 P NMR (243 MHz, Dichloromethane-d2) δ 36.52, 35.14.

[0300] HRMS(ESI) [M-Br] + Calculated value: 807.3912, Experimental value: 807.3907.

[0301] Example 6: Preparation of palladium complex L4-Pd-G6

[0302] Following the same procedure as in Example 5, except that the ligand is changed to L4, the target complex L4-Pd-G6 is obtained:

[0303]

[0304] Yellow solid, 89% yield, melting point 112 – 113°C.

[0305] 1H NMR (600 MHz, Dichloromethane-d2) δ 7.54 – 7.38 (m, 5H), 6.88 (s,2H), 4.31 (brs, 2H), 3.73 (s, 3H), 2.88 (brs, 2H), 2.28 – 2.19 (m, 2H), 1.99– 1.97 (m, 1H), 1.80 – 1.67 (m, 8H), 1.59 – 1.40 (m, 11H), 1.25 – 1.23 (m,4H), 1.08 – 1.06 (m, 4H), 0.66 (brs, 1H), 0.06 (s, 9H).

[0306] 13 C NMR (151 MHz, Dichloromethane-d2) δ 167.9, 161.0, 158.7, 137.7,136.2, 129.2, 128.0, 126.5, 125.8, 114.5, 63.0, 55.8, 47.3, 46.2, 46.1, 45.8,41.3, 39.2, 37.0, 36.5, 34.6, 32.3, 31.4, 31.3, 30.2, 29.4, 29.3, 29.2, 28.2,28.1, 28.0, 27.53, 27.46, 27.0, 26.71, 26.67, 17.7, -1.2.

[0307] 31 P NMR (243 MHz, Dichloromethane-d2) δ 31.16, 29.37.

[0308] HRMS(ESI) [M-Br] + Calculated value: 725.2766, Experimental value: 725.2762.

[0309] Application Example 1: Palladium complex (L-Pd-G6) as a catalyst in the Buchwald-Hartwig reaction for the synthesis of triarylamines.

[0310]

[0311] In an argon-filled glove box, sodium tert-butoxide (96.1 mg, 1 mmol), 4A molecular sieve (50 mg, used to remove moisture from the reaction system), dried o-xylene (1 mL), diphenylamine (0.5 mmol), and bromobenzene (0.65 mmol) were added sequentially to the sample vials. Then, the corresponding palladium [Pd] catalysts listed in Table 1 were added (all in 0.01 mg / mL o-xylene solution, the amount added being such that the concentration of palladium in the reaction system was the corresponding concentration in Table 1), and L7-BH3 (1 mg / mL o-xylene solution; 24 μL). The sample vials were sealed and removed from the glove box, then heated to reflux for 48 h. After the reaction was complete, the mixture was filtered, the solvent was removed by vacuum distillation, and the residue was purified by silica gel chromatography (eluent: petroleum ether / ethyl acetate) to obtain the final product. The yields obtained by gas chromatography (GC) are shown in Table 1.

[0312] 1 H NMR (600 MHz, Chloroform-d) δ 7.24 – 7.21 (m, 6H), 7.08 (d, J =8.7 Hz, 6H), 6.99 (t, J = 7.4 Hz, 3H).

[0313] 13 C NMR (151 MHz, Chloroform-d) δ 148.0, 129.3, 124.3, 122.8.

[0314] Table 1

[0315]

[0316] As can be seen from the data in Table 1, compared with existing palladium catalysts, the palladium complex of the present invention, combined with the adduct of the present invention L-BH3, exhibits significantly higher catalytic activity and achieves better catalytic effect in the Buchwald-Hartwig reaction at the same or lower palladium concentration.

[0317] Application Example 2: Effect of the amount of adduct L7-BH3 on the yield of triarylamine synthesis in the Buchwald-Hartwig reaction using palladium complex (L7-Pd-G6) as a catalyst.

[0318]

[0319] Following the same procedure as in Application Example 1, except that an appropriate amount (eq.) of the ligand borane adduct (L7-BH3) from Table 3 was added, and the product yields obtained by gas chromatography (GC) are shown in Table 3 below.

[0320] Table 2

[0321]

[0322] As can be seen from Table 2, even in very low amounts, the adduct L-BH3 of the present invention enhances the catalytic activity of the complex of the present invention as a catalyst in the Buchwald-Hartwig reaction, with a turnover number (TON) as high as 49,000.

[0323] Application Example 3: Palladium complexes as catalysts for the synthesis of diarylamines from primary amines and haloaromatics via the Buchwald-Hartwig reaction.

[0324]

[0325] In an argon-filled glove box, sodium tert-butoxide (96.1 mg, 1 mmol), 4A molecular sieve (50 mg), dried o-xylene (1 mL), aniline (0.5 mmol), and bromobenzene (0.65 mmol) were added sequentially to the sample vial. Then, palladium [Pd] catalyst L4-Pd-G6 (0.1 mg / mL o-xylene solution, 72.5 μL) and L4-BH3 (1 mg / mL o-xylene solution, 21.4 μL) were added. The sample vial was sealed and removed from the glove box, then heated to reflux for 24 h. After the reaction was complete, the mixture was filtered, the solvent was removed by vacuum distillation, and the residue was purified by silica gel chromatography (eluent: petroleum ether / ethyl acetate) to obtain the final product in 99% yield.

[0326] 1 H NMR (600 MHz, Chloroform-d) δ 7.33 – 7.26 (m, 4H), 7.12 (d, J =7.4 Hz, 4H), 6.98 (t, J = 7.4 Hz, 2H), 5.72 (brs, 1H).

[0327] 13 C NMR (151 MHz, Chloroform-d) δ 143.2, 129.5, 121.1, 117.9.

[0328] As can be seen from the above data, compared with existing palladium catalysts, the palladium complex of the present invention has significantly higher catalytic activity in the Buchwald-Hartwig reaction at the same or lower palladium concentration.

[0329] Application Example 4: Palladium complexes as catalysts for the synthesis of aryl cyclic amines from cyclic secondary amines and haloaromatics via the Buchwald-Hartwig reaction.

[0330]

[0331] In an argon-filled glove box, sodium tert-butoxide (96.1 mg, 1 mmol), 4A molecular sieve (50 mg), dried o-xylene (1 mL), morpholine (43.5 mg, 0.5 mmol), and chlorobenzene (73.1 mg, 0.65 mmol) were added sequentially to the sample vial. Subsequently, the corresponding palladium [Pd] catalyst (0.01 mg / mL o-xylene solution, 16 μL) and L7-BH3 (1 mg / mL o-xylene solution; 24 μL) from Table 5 were added. The sample vial was sealed and removed from the glove box, then heated to reflux for 24 h. After the reaction was complete, the mixture was filtered, the solvent was removed by vacuum distillation, and the residue was purified by silica gel rapid chromatography (eluent: petroleum ether / ethyl acetate) to obtain the final product in 99% yield.

[0332] 1 H NMR (600 MHz, Chloroform-d) δ 7.31 – 7.28 (m, 2H), 6.93 (d, J =7.7 Hz, 2H), 6.90 (t, J = 7.3 Hz, 1H), 3.87 (d, J = 4.8 Hz, 4H), 3.17 (d, J =4.8 Hz, 4H).

[0333] 13 C NMR (151 MHz, Chloroform-d) δ 151.4, 129.3, 120.2, 115.8, 67.1, 49.5.

[0334] Application Example 5: Application of palladium complexes as catalysts in the synthesis of triarylamine-based OLED material molecules

[0335]

[0336] In an argon-filled glove box, L7-BH3 (2.5 mg, 0.005 mmol), sodium tert-butoxide (9.61 g, 100 mmol), 4A molecular sieve (5 g), dried mesitylene (100 mL), 4,4'-dibromo-1,1'-biphenyl (7.80 g, 25 mmol), 3-methyl-N-phenylaniline (9.35 g, 51 mmol), and 444 μL of a mesitylene solution of L7-Pd-G6 (concentration 1 mg / mL, containing 0.0005 mmol Pd) were added sequentially to a 350 mL pressure-resistant reaction vessel. The reaction vessel was sealed, removed from the glove box, and heated at 195 °C for 48 h. After the reaction was complete, the reaction mixture was filtered and washed with dichloromethane. After the filtrate was concentrated under reduced pressure to remove the solvent, the product was obtained by recrystallization from ethanol, and finally 12.5 g of the target product p-TPD (24.2 mmol, yield 97%) was obtained.

[0337] 1 H NMR (600 MHz, Chloroform-d) δ 7.46 (d, J = 8.7 Hz, 4H), 7.28 –7.25 (m, 4H), 7.18 – 7.15 (m, 2H), 7.13 – 7.11 (m, 8H), 7.02 (t, J = 7.3 Hz,2H), 6.97 (s, 2H), 6.94 (d, J = 7.7 Hz, 2H), 6.86 (d, J = 7.7 Hz, 2H), 2.28(s, 6H).

[0338] 13 C NMR (151 MHz, Chloroform-d) δ 147.9, 147.8, 146.9, 139.3, 134.7,129.3, 129.2, 127.4, 125.2, 124.3, 124.2, 124.0, 122.8, 121.8, 21.6.

[0339] Application Example 6: Following the same procedure as in the previous application examples, the following OLED material molecules were synthesized:

[0340] 2,2',7,7'-Tetra(diphenylamino)-9,9'-spirodifluorene (spiro-TAD):

[0341]

[0342] The product was purified by recrystallization using a mixed solvent of ethanol and tetrahydrofuran (403.9 mg, yield 82%).

[0343] 1 H NMR (600 MHz, Chloroform-d) δ 7.46 (d, J = 8.3 Hz, 4H), 7.22 –7.19 (m, 16H), 7.01 – 6.96 (m, 24H), 6.93 (d, J = 8.3 Hz, 4H), 6.71 (s, 4H).

[0344] 13 C NMR (151 MHz, Chloroform-d) δ 150.1, 147.9, 146.9, 136.9, 129.2, 125.2, 123.5, 122.4, 120.6, 120.4, 66.6.

[0345] N,N'-Di(naphthyl-2-yl)-N,N'-Di(phenyl)biphenyl-4,4'-diamine (NPB):

[0346]

[0347] The product was purified by recrystallization using a mixed solvent of ethanol and tetrahydrofuran (285.6 mg, 97% yield).

[0348] 1 H NMR (600 MHz, Chloroform-d) δ 7.77 (d, J = 8.1 Hz, 2H), 7.74 (d, J= 8.8 Hz, 2H), 7.61 (d, J = 8.1 Hz, 2H), 7.50 – 7.48 (m, 6H), 7.42 – 7.39 (m,2H), 7.37 – 7.35 (m, 2H), 7.33 (d, J = 8.8 Hz, 2H), 7.31 – 7.28 (m, 4H), 7.19– 7.18 (m, 8H), 7.07 (t, J = 7.3 Hz, 2H).

[0349] 13 C NMR (151 MHz, Chloroform-d) δ 147.8, 146.8, 145.5, 135.1, 134.6,130.2, 129.5, 129.1, 127.7, 127.5, 127.1, 126.4, 124.67, 124.63, 124.58,124.46, 123.2, 120.5.

[0350] 9,9-Dimethyl-N,N'-diphenyl-N,N'-di-m-tolylfluorene-2,7-diamine (DMFL-TBD):

[0351]

[0352] The product was purified by recrystallization using a mixed solvent of ethanol and tetrahydrofuran (270.6 mg, 97% yield).

[0353] 1 H NMR (600 MHz, Chloroform-d) δ 7.49 (d, J = 8.0 Hz, 2H), 7.26 –7.24 (m, 4H), 7.16 – 7.11 (m, 8H), 7.01 – 6.99 (m, 4H), 6.96 (s, 2H), 6.93 (d, J = 8.0 Hz, 2H), 6.84 (d, J = 7.4 Hz, 2H), 2.27 (s, 6H), 1.35 (s, 6H).

[0354] 13 C NMR (151 MHz, Chloroform-d) δ 155.1, 148.2, 148.1, 146.8, 139.1,134.1, 129.3, 129.1, 124.8, 124.0, 123.7, 123.6, 122.4, 121.3, 120.1, 118.9,46.9, 27.1, 21.6.

[0355] 4,4',4''-Tris(diphenylamino)triphenylamine (NATA):

[0356]

[0357] The product was purified by recrystallization using a mixed solvent of ethanol and tetrahydrofuran (313.7 mg, yield 84%).

[0358] 1 H NMR (600 MHz, Benzene-d6) δ 7.13 (d, J = 8.8 Hz, 12H), 7.06 – 7.03(m, 18H), 6.97 (d, J = 8.8 Hz, 6H), 6.83 (t, J = 7.3 Hz, 6H).

[0359] 13C NMR (151 MHz, Benzene-d6) δ 148.5, 143.5, 143.1, 129.6, 126.1, 125.2, 124.2, 122.8.

[0360] The above description is merely a preferred embodiment of the present invention. However, the scope of protection of the present invention is not limited thereto; any equivalent substitutions or modifications made by those skilled in the art within the technical scope of the present invention, based on the technical solution and its improved concepts, should be covered within the scope of protection of the present invention.

Claims

1. A palladium complex modified with a norbornene skeleton monophosphine ligand L, characterized in that, The palladium complex has a structure represented by the formula L-Pd-G6: Where L is a group consisting of... The structure represents a norbornene skeleton monophosphine ligand, and the ligand L is connected to the palladium complex via a P atom to form the complex, wherein Ar is selected from C. 6-10 Aryl or C 6-10 heteroaryl; R 1 and R 2 Each is independently selected from C that is arbitrarily substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 2-8 Alkenyl, C substituted with one or more halogens 2-8 Alkyne group, C group optionally substituted with one or more halogens 3-8 cycloalkyl, C 6-10 Aryl or C 6-10 heteroaryl, of which the C mentioned above 6-10 Aryl or C 6-10 Each heteroaryl group is independently selected from 1 to 5 C 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Alkoxy, halogen, hydroxyl, amino, C 1-8 Alkylamino, diC 1-8 Alkylamino, C 1-8 Acyl group, C 2-8 Acyloxy group, C 2-8 ester group or C 1-8 The acylamino group is substituted, and the C 6-10 The heteroaryl group contains 1-3 heteroatoms selected from N, S or O; and TMS is trimethylsilyl.

2. The palladium complex according to claim 1, characterized in that, In the ligand L, Ar is selected from phenyl or naphthyl, wherein each of the phenyl or naphthyl groups is independently and optionally composed of 1-3 C-terminal groups. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

3. The palladium complex according to claim 1, characterized in that, In the ligand L, R 1 and R 2 Each is independently selected from C that is arbitrarily substituted with one or more halogens. 1-8 Alkyl groups, C substituted with one or more halogens 3-8 Cycloalkyl or phenyl, wherein the phenyl group is optionally composed of 1-3 C16 atoms. 1-8 Alkyl, Halogenated C 1-8 Alkyl, C 1-8 Substitution with alkoxy, halogen, hydroxyl, or amino groups.

4. The palladium complex according to claim 1, characterized in that, The palladium complex has a structure represented by the formula L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6 or L8-Pd-G6, or a racemic or enantiomer thereof: L1, L2, L3, L4, L5, L6, L7, and L8 are the norcamphorane skeleton monophosphine ligands of complexes L1-Pd-G6, L2-Pd-G6, L3-Pd-G6, L4-Pd-G6, L5-Pd-G6, L6-Pd-G6, L7-Pd-G6, or L8-Pd-G6, respectively.

5. A method for preparing the palladium complex according to claim 1, the method comprising: In the presence of an organic solvent and a palladium catalyst, halogenated norbornene or its analogues are subjected to a hydroarylation reaction with aryl halides or aryl sulfonates to obtain aryl-substituted halogenated norbornene intermediate S2. Make the intermediate S2 and R 1 R 2 PCl undergoes a substitution reaction to yield the norcamphorane skeleton monophosphine ligand L; The norbornene skeleton monophosphine ligand L is reacted with palladium precursor S3 and 2-(trimethylsilyl)ethyl-4-bromobenzyl ester to obtain the desired palladium complex. , where cod represents 1,5-cyclooctadiene.

6. The method according to claim 5, characterized in that, The ligand L obtained from the substitution reaction is reacted with a borane solution to give the borane adduct L-BH3 of the ligand L: Furthermore, if necessary, the adduct L-BH3 can be deprotected from its borane protecting group in the presence of an organic base deprotecting agent to obtain the norcamphorane skeleton monophosphine ligand L.

7. The method according to claim 5, characterized in that, The hydrogen arylation reaction is carried out in the presence of a negative hydrogen source, preferably triethylamine and formic acid; preferably the hydrogen arylation reaction is carried out at 0-150°C; preferably the organic solvent is one or more selected from dimethyl sulfoxide, benzene, toluene, tetrahydrofuran, ethyl acetate and acetonitrile.

8. The method according to claim 5, characterized in that, In relation to R 1 R 2 Before the substitution reaction of PCl, the intermediate S2 is subjected to a lithium halide exchange reaction with alkyl lithium; preferably, the alkyl lithium is tert-butyl lithium or n-butyl lithium.

9. An adduct L-BH3 of a norbornene skeleton monophosphine ligand L and borane for preparing palladium complexes according to any one of claims 1-4, characterized in that, The adduct has the following structure: 。 10. The application of the palladium complex according to any one of claims 1-4 as a catalyst in promoting CN coupling reactions in organic synthesis, preferably the palladium complex is used in combination with the adduct L-BH3 according to claim 9.

11. An organic compound, preferably a pharmaceutical, pesticide, or functional material compound, characterized in that, The organic compound contains a CN structural unit formed by a CN coupling reaction promoted by using a palladium complex as a catalyst according to any one of claims 1-4, preferably the palladium complex is used in combination with the adduct L-BH3 according to claim 9.

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