RUTHENIUM COMPLEXES AND THEIR USE IN CHEMICAL REACTIONS
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- UNIV OF MANCHESTER
- Filing Date
- 2023-06-20
- Publication Date
- 2026-04-15
AI Technical Summary
Existing cross-coupling reactions in organic chemistry require functionalized starting materials with halides or boronic acids and precious metals like palladium, and existing ruthenium catalysts are not air-stable.
Development of air-stable ruthenium complexes that catalyze the conversion of C-H bonds to C-C bonds at temperatures up to 120°C, using ruthenium complexes of formula (I) with specific ligands and anions, allowing the reaction to proceed in the presence of non-functionalized substrates.
The air-stable ruthenium complexes efficiently convert C-H bonds to C-C bonds under mild conditions, offering a stable and efficient alternative to traditional palladium-based catalysts.
Description
Background
[0001] Cross-coupling reactions are widespread in organic chemistry, such as Suzuki coupling reactions in which a carbon-carbon bond is formed in a Pd catalyst mediated reaction between an aryl halide and an aryl boronic acid, and Heck reactions in which a carbon-carbon bond is formed in a Pd catalyst mediated reaction between an unsaturated compound substituted with a halide and an alkene.
[0002] Such reactions require one or both starting materials to have a functionalised group such as a halide or boronic acid group and require precious metals such as palladium.
[0003] L. Guillemard, N. Kaplaneris, L. Ackermann and M. J. Johansson, "Late-stage C-H functionalization offers new opportunities in drug discovery" Nat. Rev. Chem., 2021, 5, 522-545 discloses late-stage C-H functionalization of drugs and drug-like compounds, and describes how the implementation of this can allow increased efficiency in the drug discovery process.
[0004] Simonetti, M., Cannas, D.M., Just-Baringo, X., Citorica-Yrezabal I.J. and Larossa I. "Cyclometallated ruthenium catalyst enables late-stage directed arylation of pharmaceuticals", Nature Chem 10, 724-731 (2018) discloses a C-H arylation catalyst of formula:
[0005] The benzylamine ligand is included in view of a proposed reaction mechanism in which a substrate having a C-H bond and a nitrogen directing group forms a cyclometalating ligand with Ru(II):
[0006] However, this Ru(II) catalyst is not air-stable.
[0007] Aebischer et al, Inorg. Chem. 1998, 37, 5915-5924, "Mechanism of Complex Formation of Ruthenium(II) Aquacomplexes with H 2 C=CH 2 , MeCN, Me 2 SO, and CO: Metal-Water Bond Rupture as Rate-Determining Step" discloses the in situ formation of complexes having 1, 2 or 3 MeCN ligands formed during reaction of [Ru(H 2 O) 6 ] 2+< with excess acetonitrile.
[0008] It is therefore an object of the invention to provide a catalyst for conversion of a C-H bond of a substrate to a C-C bond. It is a further object of the invention to provide an air-stable catalyst for such conversions.Summary of the Invention
[0009] In a first aspect, the invention provides a compound of formula (I-A): wherein R 1< in each occurrence is selected from H, optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl; R 2< in each occurrence is selected from optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl; p' is 1 and q' is 5 or p' is 2 and q' is 4; p + q = 6; Y is an anion; and n is 1 or 2.
[0010] Optionally, p' is 1 and q' is 5.
[0011] Optionally, each R 1< is H.
[0012] Optionally, n is 2.
[0013] Optionally, Y is a borate, phosphate or perchlorate anion.
[0014] In a second aspect, the invention provides a method of forming a compound according to the first aspect, the method comprising reducing a compound of formula RuZ 3 in the presence of a compound of formula R 2< -CN to form an intermediate and reacting the intermediate with a compound of formula R 1< 2 O, wherein Z is an anionic ligand.
[0015] Optionally, Z is a halide.
[0016] Optionally, the RuZ 3 is reduced by a reducing agent. Optionally, the reducing agent is zinc.
[0017] Optionally, the RuZ 3 is reduced electrochemically.
[0018] In a third aspect, the invention provides a method of forming a compound according to any the first aspect, the method comprising reacting a compound of formula RuZp'(NC-R 2< )q' with a compound of formula R 1< 2 O wherein Z is an anionic group.
[0019] Optionally according to the third aspect, the reaction is performed the presence of a compound of formula M +< Y -< wherein M +< is a cation
[0020] In a fourth aspect, the invention provides a method of forming a compound of formula (C), the method comprising a reaction according to Scheme 1: wherein (A) is a compound or a compound fragment; Ar 1< is an aromatic or heteroaromatic group which is unsubstituted or substituted with one or more substituents; DG is a directing group; R 3< is an aryl, heteroaryl, alkyl, alkenyl or alkynyl group; and X is a leaving group, and wherein the reaction is catalysed by a compound of formula (I): wherein R 1< in each occurrence is selected from H, optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl; R 2< in each occurrence is selected from optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl; p is at least 1; q is at least 1; p + q = 6; Y is an anion; and n is 1 or 2.
[0021] Optionally, the method is according to Scheme 2:
[0022] Optionally, the compound or compound fragment of formula (A) has formula (A-2) or (A-3): wherein R 4< - R 7< , are each independently H or a substituent, R 4< and R 5< may be linked to form an optionally substituted monocyclic or fused ring; and R 6< and R 7< may be linked to form an optionally substituted monocyclic or fused ring.
[0023] Optionally, R 4< , R 6< and R 7< are each independently H, optionally substituted C 1-6 alkyl, optionally substituted C 6-20 aryl or -C(=O)R 11< wherein R 11< is C 1-6 alkyl or optionally substituted C 6-20 aryl.
[0024] Optionally, R 5< is optionally substituted C 1-6 alkyl, optionally substituted C 6-20 aryl or - C(=O)R 11< wherein R 11< is C 1-6 alkyl or optionally substituted C 6-20 aryl.
[0025] Optionally, the compound or compound fragment of formula (A) has formula (A-4): wherein Ar 2< is an optionally substituted monocyclic or fused heteroaromatic ring.
[0026] Optionally, Ar 2< has C and N ring atoms and, optionally, O or S ring atoms.
[0027] Optionally, the compound or compound fragment of formula (A) has formula (A-5) or (A-6): wherein R 6< and R 7< are each independently H or a substituent, and R 6< and R 7< may be linked to form an optionally substituted monocyclic or fused ring.
[0028] Optionally, the compound or compound fragment of formula (A) has formula (A-7): wherein Z 1< , Z 2< and Z 3< are each independently N or CR 8< wherein R 8< is H or a substituent.
[0029] In some embodiments, X is bound to an aromatic carbon atom of R 3< . In these embodiments, R 3< may be an optionally substituted C 6-20 aryl, preferably optionally substituted phenyl, or optionally substituted 5-20 membered heteroaryl group.
[0030] In some embodiments, X is bound to a sp 3< hybridised primary or secondary carbon atom.
[0031] In these embodiments, R 3< is an optionally substituted C 1-12 alkyl.Drawings
[0032] The invention will be described with reference to the drawings in which: Figure 1 is a 1< H NMR spectrum of Compound 2 according to an embodiment of the invention after exposure to air; Figure 2A is a 1< H NMR spectrum of Comparative Compound 1 before exposure to air Figure 2B is a 1< H NMR spectrum of Comparative Compound 1 after exposure to air; and Figure 2C shows stacked spectra of Figures 2A and 2B. Detailed Description
[0033] The present inventors have found that compounds of formula (I) are air-stable and can be used for conversion of one or more C-H bonds of an aromatic carbon atom to one or more corresponding C-C bonds:
[0034] The present inventors have further found that compounds of formula (I) may be capable of catalysing such conversions at temperatures of no more than about 120°C, for example in the range of 0-120°C, optionally in the range of 0-80°C or 0-50°C.
[0035] R 1< in each occurrence may be the same or different and is selected from H, optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl. Preferably, each R 1< is H, i.e. R 1< 2 O is water.
[0036] R 2< in each occurrence is selected from optionally substituted C 1-12 alkyl and optionally substituted C 6-20 aryl.
[0037] Each of p and q is at least 1, and p + q = 6.
[0038] Preferably, p is 1 and q is 5.
[0039] Y is an anion and n is 1 or 2. Preferably, n is 2. Y may be any suitable non-coordinating anion known to the skilled person, for example BF 4 -< ,PF 6 -< or ClO 4 -< .
[0040] A preferred compound of formula (I) is [Ru(OH 2 )(R 2< CN) 5 ] 2Y -< wherein R 2< is preferably a C 1- 6 linear, branched or cyclic alkyl group.
[0041] Without wishing to be bound by any theory, in use the R 1< 2 O ligand is replaced by the compound or compound fragment of formula (A) to form an intermediate which is bound to Ru through a coordinating atom of the directing group DG.Formula (A)
[0042] The compound or compound fragment of formula (A) consists of or comprises a fused or monocyclic aromatic or heteroaromatic ring Ar 1< bound to a directing group DG:
[0043] Ar 1< may be a monocyclic or fused aromatic or heteroaromatic ring, optionally a C 5-20 aromatic ring or a 5-20 membered heteroaromatic ring. A preferred Ar 1< is a benzene ring. In the case where the group of formula (A) is a compound fragment, the group of formula (A) forms part of a larger molecule, e.g. a pharmaceutical compound. It will be appreciated that the structure of the larger molecule is not particularly limited. The molecule may contain only one fragment of formula (A). The molecule may contain two or more fragments of formula (A).
[0044] The directing group DG is a group capable of coordinating to Ru of the catalyst of formula (I) and steering reaction at a carbon atom of a C-H group of Ar 1< . The C atom of the C-H group is preferably ortho or meta to the carbon atom to which DG is bound. The present inventors have found that the Ru catalyst of formula (I) tends to be ortho-selective for reactions with an aromatic halide or a primary or secondary alkyl halide and meta-selective for reactions with a tertiary alkyl halide.
[0045] It will be understood that both DG and Ar 1< may be substituted with a wide range of substituents, which may be selected according to the structure of a desired end-product or intermediate. Optionally, the or each substituent has a molecular weight of less than 1000 Da.
[0046] A preferred compound or compound fragment of formula (A) has formula (A-1):
[0047] DG may comprise a coordinating group comprising a O, S or N coordinating atom, preferably a N atom.
[0048] In some embodiments, the compound or fragment of formula (A) has formula (A-2) or (A-3):
[0049] R 4< , R 5< , R 6< and R 7< are each independently H or a substituent.
[0050] R 4< and R 5< may be linked to form an optionally substituted monocyclic or fused ring.
[0051] R 6< and R 7< may be linked to form an optionally substituted monocyclic or fused ring.
[0052] - - - - represents a carbon-carbon single bond or carbon-carbon double bond.
[0053] Optionally, R 4< and R 5< are linked to form a non-aromatic, optionally fused ring, for example: wherein R 20< is a C 1-20 hydrocarbyl group, preferably a C 1-12 alkyl group; R 21< in each occurrence is a substituent, optionally a halogen, more preferably Cl; and v is 0, 1, 2, 3 or 4.
[0054] Optionally, R 4< and R 5< are linked to form an optionally substituted monocyclic or fused heteroaryl of formula (A-4):
[0055] Ar 2< is a fused or monocyclic heteroaromatic ring.
[0056] Ar 2< may be a monocyclic or fused heteroaromatic ring, optionally a 5-20 membered heteroaromatic ring. Preferred heteroaromatic rings have C and N ring atoms and, optionally, O or S ring atoms.
[0057] The compound of formula (A) is optionally a compound of formula (A-5) or (A-6):
[0058] Optionally, R 6< and R 7< of (A-5) are linked to form an optionally substituted monocyclic or fused heteroaryl of formula (A-7) wherein Z 1< , Z 2< and Z 3< are each independently N or CR 8< wherein R 8< is H or a substituent.
[0059] Exemplary DG groups include, without limitation: wherein Z 3< is O, S or NR 9< ; R 8< in each occurrence is independently H or a substituent; R 9< is H or a substituent; w is at least 1, optionally 1, 2, 3, 4 or 5; and two R 8< groups bound to the same C atom or bound to adjacent C atoms or an R 8< group and an R 9< group bound to adjacent C and N atoms may be linked to form an unsubstituted or substituted ring.
[0060] Optionally, R 8< in each occurrence is independently selected from H, F, optionally substituted phenyl, optionally substituted C 1-12 alkyl, OR 30< , SR 30< , COOR 30< , C(=O)R 30< , CONR 30< or NR 30< wherein R 30< in each occurrence is H; or an optionally substituted monocyclic or fused C 6-12 aryl, preferably optionally substituted phenyl, or an optionally substituted monocyclic or fused C 5-20 heteroaryl group.
[0061] Optionally, R 9< is H; branched, linear or cyclic C 1-12 alkyl; or optionally substituted C 6-12 aryl or optionally substituted C 5-20 heteroaryl.
[0062] Optional substituents of an optionally substituted alkyl group as described anywhere herein include F, CN, NO 2 , or an optionally substituted aryl or heteroaryl group.
[0063] Optional substituents of an optionally substituted aryl or heteroaryl group as described anywhere herein include F, Cl, CN, NO 2 , or C 1-12 alkyl in which one or more non-adjacent C atoms of the C 1-12 alkyl may be replaced with O, S, COO, C(=O), CONR 31< or NR 31< wherein R 31< in each occurrence is H or a C 1-20 hydrocarbyl group.
[0064] Two R 8< groups linked to adjacent carbon atoms or an R 8< group and an R 9< group bound to adjacent C and N atoms may be linked to form an optionally substituted benzene, or azine ring, such as a pyridine or diazine ring, for example:
[0065] For simplicity, the compound or compound fragment of formula (A) as illustrated above shows only one C-H group, however it will be appreciated that two C-H groups may be available for reaction, for example two ortho C-H groups as illustrated below: Compound B
[0066] Compound B has formula R 3< -X.
[0067] X is bound to a carbon atom of R 3< , preferably an sp 3< -hybridised, primary or secondary carbon atom or an sp 2< -hybridised carbon atom of an aromatic or heteroaromatic ring.
[0068] It will be understood that a wide range of R 3< groups may be used, according to the desired product of the reaction between compounds A and B, and as such other constituent atoms or units of R 3< are not particularly limited.
[0069] It will be appreciated that a wide range of optional substituents may be selected according to the desired product. R 3< may be selected from, without limitation, optionally substituted C 1-40 alkyl; optionally substituted C 2-40 alkenyl; optionally substituted C 2-40 alkynyl; optionally substituted C 6-20 aryl, preferably optionally substituted phenyl; and an optionally substituted 5-20 membered heteroaromatic group, wherein one or more non-adjacent -CH 2 - groups of the C 1-12 alkyl, C 2-12 alkenyl, or C 2-12 alkynyl may be replaced with O, S, COO, CO, CONR 31< or NR 3< . . Where present, the or each substituent preferably has a molecular weight of less than 1000 Da.
[0070] In the case where R 3< is an optionally substituted C 1-12 alkyl group, R 3< -X may be a primary, secondary (including cyclic) or tertiary optionally substituted alkyl group, preferably a primary or secondary optionally substituted alkyl group.
[0071] X is a leaving group, preferably Cl, Br or I, preferably Br; a pseudohalid, preferably a sulfonate, for example tosylate or triflate; or a group of formula -N(R 10< ) 3 +< An -< wherein R 10< in each occurrence is a substituent and An -< is an anion.
[0072] Preferably, each R 10< is independently selected from the group consisting of optionally substituted C 1-12 alkyl, optionally substituted aryl e.g. optionally substituted phenyl, more preferably selected from C 1-12 alkyl and phenyl which is optionally substituted with one or more substituents selected from F, C 1-6 alkyl and C 1-6 fluoroalkyl.
[0073] An -< may be any suitable anion, for example a halide or a sulfonate such as triflate.
[0074] Many known compounds, including but not limited to pharmaceuticals or intermediates thereof, contain an aromatic C-H group adjacent to a group capable of acting as a directing group.
[0075] Examples of Compound B include, without limitation:
[0076] Examples of pharmaceuticals which may be formed by a method as described herein include the following, in which bonds shown with a dashed line extending through them are formed upon functionalisation of a C-H bond as described herein:
[0077] Examples of products of a reaction between a compound having a primary alkyl halide group and a known compound include the following:
[0078] Examples of products of a reaction between a compound having a secondary alkyl halide group and a known compound include the following:
[0079] An optionally substituted C 6-20 aryl group as described herein with reference to a compound of formula (I), a compound of formula (I-A), Compound A or Compound B is preferably a C 6-12 aryl, e.g. phenyl. The C 6-20 aryl group may be, without limitation, a single monocyclic ring; a fused monocyclic aromatic group; or combinations thereof linked by a single bond.Catalyst synthesis
[0080] One method of forming a catalyst as described herein is reduction of a Ru 3+< compound in the presence of R 2< -CN to form an intermediate which is then reacted with a compound of formula R 1< 2 O.
[0081] Reduction of a Ru 3+< compound may be performed electrochemically or by a reducing agent capable of reducing Ru 3+< to Ru 2+< . An exemplary reducing agent is an elemental metal capable of reducing Ru 3+< to Ru 2+< , for example zinc.
[0082] The Ru 3+< compound may be, for example, a Ru (III) halide, e.g. RuBr 3 , RuCl 3 or RuI 3 .
[0083] Another method of forming a catalyst as described herein is replacement of an anionic ligand Z in a compound RuZp'(NC-R 2< )q' with a compound of formula R 1< 2 O. The reaction may be performed in the presence of a compound of formula M +< Y -< for providing a counterion Y -< of the catalyst, wherein M +< is a cation, e.g. a metal ion. In the case where p' is 1 and q' is 5, it will be appreciated that RuZp'(NC-R 2< )q' is cationic and will comprise a suitable anionic counterion.Examples General Information
[0084] All the starting materials and solvents were purchased from Acros (Fisher), Aldrich (Merck), Alfa Aesar (Fisher), Fluorochem and Generon and used without further purification unless otherwise stated. Column chromatography was carried out on silica gel (particle size 40-63 µm) using flash techniques. High resolution mass spectra were performed by the School of Chemistry Mass Spectrometry Service (University of Manchester) employing a Thermo Finnigan MAT95XP spectrometer. IR spectra were recorded using a Thermo Scientific Nicolet iS5 FTIR machine, relevant bands are quoted in cm -1< . 1< H NMR, 19< F NMR and 13C< NMR spectra were recorded at 400 or 500 on Bruker instruments. 1< H NMR are referenced to the residual solvent peak at 7.26 ppm (CDCl 3 ), 5.35 (CD 2 Cl 2 ) or 2.05 ppm ((CD 3 ) 2 CO). ppm values are quoted to 2 decimal places, with coupling constants (J) to the nearest 0.1 Hz. 13< C NMR spectra were recorded at 151, 126 or 100 MHz and quoted in ppm to 1 decimal place with coupling constants (J) to the nearest 0.1 Hz. The spectra were referenced to the residual solvent peak at 77.16 ppm (CDCl 3 ), 5.30 ppm (CD 2 Cl 2 ) or 39.52 ppm ((CD 3 ) 2 CO). 19< F NMR spectra recorded at 471 or 376 MHz in CDCl 3 or CD 2 Cl 2 and quoted in ppm to 2 decimal places with coupling constants (J) to the nearest 0.1 Hz.Preparation of Ruthenium Aqua Complex 2 General Procedure A1
[0085] i) Zn dust, tBuCN, 115 °C, 2 h General procedure for synthesis of ruthenium aqua catalyst 2
[0086] Pivalonitrile was dried over 4 Å molecular sieves and degassed with three freeze-pump-thaw cycles prior to use. In a glove box, RuCl 3 •×H 2 O (Reagent Grade purity ≥ 95%, 1 equiv based on anhydrous molecular weight), glove-boxed stored Zn dust (<10 µm, 3.2 equiv) and pivalonitrile were loaded in an Ace pressure tube which was subsequently wrapped in Teflon tape and parafilm. The sealed tube was then taken out from the glovebox and stirred for 2 h at 115 °C ensuring the solid was being thoroughly stirred. The reaction mixture was cooled to room temperature and the pivalonitrile removed under reduced pressure. The resulting mixture was diluted with HPLC-grade water before being filtered through a small plug of Celite ®< to remove all solids. AgBF 4 (2 equiv) was added and the reaction was vigorously stirred for 1 hour at room temperature. After this time the solution was filtered through a plug of Celite ®< and evaporated to dryness. The residue was dissolved in acetone, filtered through a plug of Celite ®< and evaporated to dryness. Then, it was dissolved in CH 2 Cl 2 , filtered through a plug of Celite ®< and evaporated to dryness. The residue was dissolved in CH 2 Cl 2 and precipitated with Et 2 O affording a light-yellow solid. The solid was collected, dissolved in CH 2 Cl 2 and precipitated with Et 2 O. The last precipitation step was reiterated until the desired complex 2 was obtained as a fluffy light-yellow powder. i) The General Procedure A1 was applied using 1.5 g (7.2 mmol) of RuCl 3 •×H 2 O, 1.5 g (22.9 mmol) of zinc dust and 35 mL of pivalonitrile. After allowing the reaction mixture to stir and removing the pivalonitrile, HPLC grade water (150 mL) and AgBF 4 (2.8 g, 14.5 mmol) were added to and the resulting reaction mixture was allowed to stir at room temperature for 1 hour. The product was precipitated with Et 2 O from a solution in DCM 5 times giving the desired complex 5 as a fluffy light-yellow solid (2.2 g, 42% yield). ii) The General Procedure A1 was applied using 20.0 g (96.0 mmol) of RuCl 3 •×H 2 O, 20.0 g (307.2 mmol) of zinc dust and 460 mL of pivalonitrile. After allowing the reaction mixture to stir and removing the pivalonitrile, HPLC grade water (2 L) and AgBF 4 (37.4 g, 192.0 mmol) were added to and the resulting reaction mixture was allowed to stir at room temperature for 1 hour. The product was precipitated with Et 2 O from a solution in DCM 6 times giving the desired complex 5 as a fluffy light-yellow solid (26.3 g, 38% yield).
[0087] 1< H NMR (500 MHz, CD 2 Cl 2 ): δ 1.43 (s, 36H), 1.38 (s, 9H).
[0088] 13< C NMR (126 MHz, CD 2 Cl 2 ): δ 135.8, 133.8, 30.8, 30.4, 28.3, 27.9.
[0089] 19< F NMR (376 MHz, CD 2 Cl 2 ) : δ -150.02, -149.97.
[0090] IR (neat, cm -1< ): 3394 (OH 2 ), 2279 (CN).
[0091] MS (ESI+ ): 622.2844.
[0092] HRMS (ESI+ ): Calculated for [Ru(OH 2 )(tBuCN) 5 ] +< (BF 4 ): 622.2848, found: 622.2848.
[0093] mp: decomposes at 180-182 °C [recrystallised by slow diffusion of diethyl ether into solution in CH 2 Cl 2 ].Procedure A2: Preparation of Ruthenium Aqua Complex 2
[0094] In a glovebox, an electrosyn ®< vial was charged with RuCl 3 •H 2 O (100 mg, 0.48 mmol, 1 equiv), TBAPF 6 (100 mg, 0.24 mmol, 0.5 equiv) and tBuCN (4 mL). The reaction vessel was sealed, removed from the glovebox, and stirred at 115 °C on an electrosyn ®< at constant voltage (1 V) for 1 hour. The reaction mixture was cooled to room temperature, filtered through a small plug of Celite ®< before washing with HPLC grade water (40 mL). AgBF 4 was added (0.96 mmol, 2 equiv,) and the reaction was vigorously stirred for 1 hour at room temperature under air in darkness before filtering through a small plug of Celite ®< and evaporating to dryness. The residue was dissolved in acetone, filtered through a small plug of Celite ®< and evaporated to dryness. Then, it was dissolved in dichloromethane, filtered through a small plug of Celite ®< and evaporated to dryness. The residue was dissolved in dichloromethane and precipitated with diethyl ether affording a light-yellow solid. The solid was collected, dissolved in dichloromethane, and precipitated with diethyl ether. The last precipitation step was reiterated another 3 times to give the desired aqua ruthenium complex 5 as an off white solid (20 mg, 6% yield).Procedure A3: Preparation of Ruthenium Aqua Complex 2
[0095]
[0096] A reaction vessel fitted with a magnetic stirrer bar was charged with ruthenium chloride intermediate 6 (341 mg, 0.68 mmol, 1 equiv) and AgBF 4 (529.3 mg, 2.72 mmol, 4 equiv). 1.8 mL of DCM and 7 mL of HPLC-grade water were added and the system was allowed to stir at room temperature for 1 hour under air in darkness before filtering through a small plug of Celite ®< and evaporating to dryness. The residue was dissolved in acetone, filtered through a small plug of Celite ®< and evaporated to dryness. Then, it was dissolved in dichloromethane, filtered through a small plug of Celite ®< and evaporated to dryness. The residue was dissolved in dichloromethane and precipitated with diethyl ether affording a light-yellow solid. The solid was collected, dissolved in dichloromethane, and precipitated with diethyl ether. The last precipitation step was reiterated another 3 times to give the desired aqua ruthenium complex 2 as a fine solid (85 mg, 18% yield).
[0097] Replacement of a H atom bound to an aromatic C atom was performed for a wide range compounds as set out in the following examples.General Procedure B: Ru-catalysed arylation of DG-containing arenes with aryl (pseudo)halides
[0098]
[0099] All liquid reagents were degassed with at least 3 freeze-pump-thaw cycles prior to use. KOAc and K 2 CO 3 were dried at 80 °C in a vacuum oven for 48 hours prior to use. Unless otherwise indicated, a 10 mL Schlenk tube equipped with a magnetic stirring bar was charged with ruthenium aqua catalyst 2 (28.4 mg, 0.04 mmol, 10 mol%), KOAc (11.8 mg, 0.12 mmol, 30 mol%), K 2 CO 3 (2-4 equiv), the appropriate DG-containing arene (0.40 mmol, 1 equiv) and the appropriate aryl halide (0.4 mmol, 1 equiv). After addition of the solids, 3 x 5 minute evac-refill cycles were performed before adding any liquid / oil reagents via injection along with the NMP (0.8 mL, 0.5 M with respect to the DG-containing arene). The vial was capped and stirred at the stated temperature for the indicated time. Upon completion, the crude mixture was loaded onto a silica gel column and purified by flash chromatography.
[0100] Data for all compounds following this procedure matches that previously reported by Larrosa et. al.
[0101] M. Simonetti, D. M. Cannas, X. Just-Baringo, I. J. Vitorica-Yrezabal and I. Larrosa, Nature Chem., 2018, 10, 724-731.
[0102] Reactions were performed as set out below following General Procedure B: * NMR yield calculated by 1< H Q NMR using trimethoxy benzene as internal standard.Synthesis of 2-(3,3',5'-trimethyl-[1,1'-biphenyl]-2-yl)pyridine (3a)
[0103]
[0104] The General Procedure B was applied with 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol, 1 equiv), br-m-xylene (74 mg, 0.40 mmol, 1 equiv), K 2 CO 3 (110.6 mg, 0.8 mmol, 2 equiv) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 ] 2 for 3 h at 40 °C. Column chromatography eluting with 5-15% EtOAc in hexane afforded the title product 3a as a colourless oil (100.5 mg, 92% yield).
[0105] 1< H NMR (400 MHz, CDCl 3 ) δ 8.65 (m, 1H), 7.46 (td, J = 7.7, 1.8 Hz, 1H), 7.35 (m, 1H), 7.30 (m, 2H), 7.12 - 7.06 (ppm, 1H), 6.92 (d, J = 7.7 Hz, 1H), 6.77 (s, 1H), 6.72 (s, 2H), 2.21 (s, 3H), 2.16 (s, 6H).
[0106] 13< C NMR (101 MHz, CDCl 3 ) δ 159.9, 148.7, 141.5, 141.5, 139.4, 137.0, 136.6, 135.7, 129.3, 128.0, 127.9, 127.9, 127.6, 125.7, 121.2, 21.2, 20.6.Synthesis of [zolimidine]-[5-m-xylene] (3b)
[0107]
[0108] The General Procedure B was applied with Zolimidine (109.0 mg, 0.40 mmol, 1 equiv), 5-br-m-xylene (109.0 µL, 0.4 mmol, 2 equiv) and K 2 CO 3 (165.8 mg, mmol, 3 equiv) for 72 h at 40 °C. Column chromatography eluting with 80% Et 2 O in hexane afforded the title product 3b as a pale yellow solid (176.8 mg, 95%).
[0109] 1< H NMR (500 MHz, CDCl 3 ) δ 7.95 (s, 2H), 7.83 (dt, J = 6.9, 1.2 Hz, 1H), 7.44 (dd, J = 9.2, 1.1 Hz, 1H), 7.07 - 7.02 (m, 1H), 6.98 (s, 1H), 6.88 (s, 4H), 6.79 (s, 2H), 6.67 - 6.62 (m, 1H), 3.12 (s, 3H), 2.14 (s, 12H).
[0110] 13< C NMR (126 MHz, CDCl 3 ): δ 145.2, 144.0, 142.7, 140.0, 139.8, 137.5, 137.1, 128.8, 127.3, 127.2, 125.4, 124.0, 117.4, 112.3, 112.0, 44.6, 21.1.Synthesis of [2-(o-tolyl)pyridine]-[trazadone] (3c)
[0111]
[0112] The General Procedure B was applied with 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol, 1 equiv), Trazodone • HCl (163.4 mg, 0.40 mmol, 1 equiv) and K 2 CO 3 (165.8 mg, 1.2 mmol, 3 equiv) at 50 °C. Column chromatography eluting with 1-5% MeOH in CH 2 Cl 2 afforded the title product 3c as an off-white solid (166.9 mg, 80%).
[0113] 1< H NMR (500 MHz, CDCl 3 ) δ 8.65 - 8.59 (m, 1H), 7.75 (dt, J = 7.0, 1.2 Hz, 1H), 7.44 (td, J= 7.6, 1.8 Hz, 1H), 7.36 - 7.31 (m, 1H), 7.31 - 7.23 (m, 2H), 7.12 - 7.01 (m, 4H), 6.90 - 6.80 (d, J= 8.9 Hz, 1H), 6.65 (m, 2H), 6.57 - 6.51 (m, 1H), 6.50 - 6.43 (m, 1H), 4.07 (t, J = 7.0 Hz, 2H), 2.92 (s, 4H), 2.55 - 2.40 (m, 6H), 2.17 (s, 3H), 2.04 (p, J = 7.1 Hz, 2H).
[0114] 13< C NMR (126 MHz, CDCl 3 ) δ 160.0, 150.5, 148.8, 148.7, 142.4, 141.8, 141.6, 139.3, 136.8, 136.0, 129.9, 129.4, 128.5, 128.1, 127.6, 125.7, 123.9, 121.4, 121.0, 118.2, 115.5, 114.1, 110.6, 55.7, 53.2, 49.0, 44.6, 26.2, 20.6Synthesis of [2-(o-tolyl)pyridine]-[Bupropion] (3d)
[0115]
[0116] General procedure B was applied. 2-(o-tolyl)pyridine (67.8 mg, 0.4 mmol, 1 equiv), bupropion HCl (110.5 mg, 0.4 mmol, 1 equiv), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (165.8 mg, 1.2 mmol, 3 equiv) were reacted in NMP (0.8 mL) at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as an internal standard indicated conversion to product 3d of 93%.Synthesis of [2-(o-tolyl)pyridine]-[chlormezanone] (3e)
[0117]
[0118] General procedure B was applied. 2-(o-tolyl)pyridine (67.8 mg, 0.4 mmol, 1 equiv), chlormezanone (109.0 mg, 0.4 mmol, 1 equiv), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3e of 90%.Synthesis of [2-(o-tolyl)pyridine]-[chlorpropham] (3f)
[0119]
[0120] The General Procedure B was applied with 2-(o-tolyl)pyridine 1 (67.8 mg, 0.40 mmol, 1 equiv), Chlorpropham (85.4 mg, 0.40 mmol, 1 equiv) and K 2 CO 3 (110.6 mg, 0.4 mmol, 2 equiv) allowing the reaction mixture to stir for 24 hours at 40 °C. Column chromatography eluting with 50% Et 2 O in hexane afforded the title product 3f as a white solid (117.7 mg, 85%).
[0121] 1< H NMR (400 MHz, CDCl 3 ) δ 8.65 - 8.60 (m, 1H), 7.46 (td, J = 7.7, 1.8 Hz, 1H), 7.37 - 7.23 (m, 4H), 7.09 (ddd, J = 7.7, 4.9, 1.2 Hz, 1H), 7.06 - 6.99 (m, 2H), 6.91 (d, J = 7.8 Hz, 1H), 6.68 (d, J = 7.6 Hz, 1H), 6.36 (bs, 1H), 4.98 (hept, J = 6.2 Hz, 1H), 2.17 (s, 3H), 1.28 (d, J = 6.2 Hz, 6H).
[0122] 13< C NMR (126 MHz, CDCl 3 ) δ 159.6, 153.2, 149.0, 142.7, 140.9, 139.4, 137.7, 136.8, 135.9, 129.7, 128.4, 128.2, 127.7, 125.7, 125.0, 121.5, 119.8, 116.6, 68.8, 22.2, 20.6.Synthesis of [2-(o-tolyl)pyridine]-[δ-tocopherol] (3g)
[0123]
[0124] The General Procedure B was applied with 2-(o-tolyl)pyridine (33.9 mg, 0.20 mmol, 1 equiv), δ-Tocopherol-OTf (106.9 mg, 0.20 mmol, 1 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol, 10 mol%) and K 2 CO 3 (55.3 mg, 0.4 mmol, 2 equiv) allowing the reaction mixture to stir for 24 hours at 40 °C. Column chromatography eluting with 10% Et 2 O in hexane afforded the title product 3g as a colourless oil (86.4 mg, 90%).
[0125] 1< H NMR (400 MHz, CDCl 3 ) δ 8.64 (d, J = 4.6 Hz, 1H), 7.46 (td, J = 7.7, 2.0 Hz, 1H), 7.35 - 7.27 (m, 2H), 7.23 (d, J = 7.2 Hz, 1H), 7.08 (dd, J = 8.0, 4.3 Hz, 1H), 6.89 (d, J = 7.7 Hz, 1H), 6.66 (s, 1H), 6.55 (s, 1H), 2.58 - 2.47 (m, 2H), 2.17 (s, 3H), 1.96 (s, 3H), 1.60-1.76 (m, 2H), 1.59 - 0.97 (m, 24H), 0.80-0.91 (m, 12H).
[0126] 13< C NMR (101 MHz, CDCl 3 ) δ 160.5, 151.0, 148.9, 141.6, 139.6, 136.8, 135.9, 132.4, 130.1, 129.0, 128.6, 128.2, 127.8, 126.0, 125.5, 121.3, 119.9, 76.3, 40.4, 39.7, 37.8, 37.6, 33.1, 33.0, 31.6, 28.3, 25.1, 24.8, 24.4, 23.1, 23.0, 22.5, 21.3, 20.9, 20.1, 20.0, 16.2.Synthesis of [2-(o-tolyl)pyridine]-[Haloperidol] (3h)
[0127]
[0128] General procedure B was applied. 2-(o-tolyl)pyridine (67.8 mg, 0.4 mmol, 1 equiv), haloperidol (149.6 mg, 0.4 mmol, 1 equiv), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as an internal standard indicated conversion to product 3h of 87%.Synthesis of [2-(o-tolyl)pyridine]-[fenofibrate] (3i)
[0129]
[0130] General procedure B was applied. 2-(o-tolyl)pyridine (67.8 mg, 0.4 mmol, 1 equiv), fenofibrate (144.4 mg, 0.4 mmol, 1 equiv), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 40 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3i of >99%.Synthesis of [2-(o-tolyl)pyridine]-[diazoxide] (3j)
[0131]
[0132] The General Procedure B was applied with 2-(o-tolyl)pyridine (97.8 mg, 0.40 mmol, 1 equiv), Diazoxide (92.2 mg, 0.40 mmol, 1 equiv) and K 2 CO 3 (110.6 mg, 0.8 mmol, 2 equiv) allowing the reaction mixture to stir at 40 °C for 48 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3j of 87%.Synthesis of [2-(o-tolyl)pyridine]-[meclizine] (3k)
[0133]
[0134] The General Procedure B was applied with 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol, 1 equiv), Meclizine • 2HCl (195.6 mg, 0.40 mmol, 1 equiv) and K 2 CO 3 (221.2 mg, 1.6 mmol, 4 equiv) at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3k of >99%.Synthesis of [diazepam]-[5-m-xylene] (3l)
[0135]
[0136] The General Procedure B was applied with diazepam (57.0 mg, 0.2 mmol, 1 equiv), I-m-xylene (58 µL mg, 0.40 mmol, 2 equiv) and K 2 CO 3 (82.9 mg, 0.6 mmol, 3 equiv) allowing the reaction mixture to stir at 40 °C for 72 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3l of 95%.Synthesis of 2-(3,3',5'-trimethyl-[1,1'-biphenyl]-2-yl)pyrimidine (3m)
[0137]
[0138] General procedure B was applied setting the reaction up in a microwave vial inside an argon filled glovebox. 2-(o-tolyl)pyrimidine (67.8 mg, 0.4 mmol, 1 equiv), br-m-xylene (74.0 mg, 0.4 mmol, 1 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol, 5 mol %), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 40 °C for 5 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3m of 97%.Synthesis of 2-(3,3",5,5"-tetramethyl-[1,1':3',1"-terphenyl]-2'-yl)benzo[d]thiazole (3n)
[0139]
[0140] General procedure B was applied setting the reaction up in a microwave vial inside an argon filled glovebox. 2-phenylbenzo[d]thiazole (42.2 mg, 0.2 mmol, 1 equiv), br-m-xylene (74.0 mg, 0.4 mmol, 1 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (7.1 mg, 0.01 mmol, 5 mol %), KOAc (5.9 mg, 0.06 mmol, 30 mol %) and K 2 CO 3 (55.3 mg, 0.4 mmol, 2 equiv) were reacted in NMP (0.4 mL) at 40 °C for 16 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3n of 75%.Synthesis of 1-(3,3',5'-trimethyl-[1,1'-biphenyl]-2-yl)-1H-pyrazole (3o)
[0141]
[0142] General procedure B was applied setting the reaction up in a microwave vial inside an argon filled glovebox. 1-(o-tolyl)-1H-pyrazole (31.6 mg, 0.2 mmol, 1 equiv), br-m-xylene (37.0 mg, 0.2 mmol, 1 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (7.1 mg, 0.01 mmol, 5 mol %), KOAc (5.9 mg, 0.06 mmol, 30 mol %) and K 2 CO 3 (55.3 mg, 0.4 mmol, 2 equiv) were reacted in NMP (0.4 mL) at 40 °C for 16 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3o of >99%.Synthesis of 2-(3',5'-dimethyl-[1,1'-biphenyl]-2-yl)-3-methylpyridine (3p)
[0143]
[0144] General procedure B was applied setting the reaction up in a microwave vial inside an argon filled glovebox. 3-methyl-2-phenylpyridine (67.8 mg, 0.4 mmol, 1 equiv), br-m-xylene (73.2 mg, 0.4 mmol, 1 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol, 5 mol %), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 40 °C for 5 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3p of 40%.Synthesis of 3',5'-dimethyl-6-(pyridin-2-yl)-[1,1'-biphenyl]-3-ol (3q)
[0145]
[0146] General procedure B was applied setting the reaction up in a microwave vial inside an argon filled glovebox. 4-(pyridin-2-yl)phenol (68.5 mg, 0.4 mmol, 1 equiv), 1-bromo-3,5-dimethylbenzene (146.4 mg, 0.4 mmol, 2 equiv), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 (2 , 14.2 mg, 0.02 mmol, 5 mol%), KOAc (11.8 mg, 0.12 mmol, 30 mol %) and K 2 CO 3 (110.5 mg, 0.8 mmol, 2 equiv) were reacted in NMP (0.8 mL) at 40 °C for 5 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 3q of 63%.General Procedure C: Ru-catalysed secondary alkylation of DG-containing arenes with secondary alkyl bromides
[0147] R 12< and R 13< are substituents which may be linked to form a ring.General procedure for the secondary alkylation of DG-containing arenes
[0148] All liquid reagents were degassed with at least 3 freeze-pump-thaw cycles prior to use. A 10 mL Schlenk tube equipped with a magnetic stirring bar was charged with ruthenium aqua catalyst 2 (14.2 mg, 0.02 mmol, 5 mol%), K 2 CO 3 (3.0 equiv), the appropriate DG-containing arene (0.40 mmol, 1 equiv) and the appropriate alkyl halide (1-2 equiv). After addition of the solids, 3 x 5 minute evac-refill cycles were performed before adding any liquid / oil reagents via injection along with the NMP (2 mL, 0.2 M with respect to the DG-containing arene). The vial was then stirred at 50 °C for the indicated time. The reaction was then allowed to cool to room temperature before being quenched with H 2 O (20 mL) and extracted with Et 2 O (3 × 20 mL). The organic extracts were combined, washed with brine (15 mL), dried over MgSO 4 , filtered and concentrated in vacuo. The residue was purified by column chromatography under the conditions noted to yield the desired product.
[0149] Reactions were performed as set out below following General Procedure C.
[0150] Data for all compounds following this procedure matches that previously reported by Larrosa et. al.
[0151] G.-W. Wang, M. Wheatley, M. Simonetti, D. M. Cannas and I. Larrosa, Chem, 2020, 6, 1459-1468. * NMR yield calculated by 1< H Q NMR using trimethoxy benzene as internal standard.Synthesis of 2-(2-cyclohexylphenyl)-3-methylpyridine (4a)
[0152]
[0153] Obtained using General procedure C employing 3-methyl-2-phenylpyridine (67.8 mg, 0.40 mmol) and bromocyclohexane (73.8 µL, 0.60 mmol). The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4a of 77%.Synthesis of 1-(2-(tetrahydro-2H-pyran-4-yl)phenyl)isoquinoline (4b)
[0154]
[0155] Obtained using General procedure C employing 1-phenylisoquinoline (94.4 mg, 0.40 mmol) and 4-bromotetrahydro-2H-pyran (47.4 µL, 0.42 mmol). The reaction was stirred at 50 °C for 24 hours. The crude mixture was purified by column chromatography eluting with 50% EtOAc in hexane to yield the title compound 4b (98.4 mg, 89%) as a colourless oil.
[0156] 1< H NMR (400 MHz, CDCl 3 ) δ 8.61 (d, J = 5.7 Hz, 1H), 7.91 (d, J = 8.3 Hz, 1H), 7.74 - 7.66 (m, 2H), 7.63 (d, J = 7.6 Hz, 1H), 7.55 - 7.40 (m, 3H), 7.42 - 7.14 (m, 1H), 7.28 (s, 1H), 3.95 - 3.87 (m, 1H), 3.88 - 3.77 (m, 1H), 3.15 (td, J = 11.4, 3.7 Hz, 1H), 3.03 - 2.93 (m, 1H), 2.50 (m, 1H), 1.90 - 1.71 (m, 3H), 1.41 - 1.33 (m, 1H).
[0157] 13< C NMR (101 MHz, CDCl 3 ) δ 161.2, 144.3, 142.1, 138.3, 136.3, 130.2, 129.9, 128.9, 128.0, 127.4, 127.2, 126.9, 126.4, 125.9, 120.0, 68.4, 68.2, 38.0, 34.1, 33.3.Synthesis of 3-methyl-2-(2-(tetrahydro-2H-pyran-4-yl)phenyl)pyridine (4c)
[0158]
[0159] Obtained using General procedure C employing 3-methyl-2-phenylpyridine (67.8 mg, 0.40 mmol) and 4-bromotetrahydro-2H-pyran (47.4 µL, 0.42 mmol). The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4c of 75%.Synthesis of 2-(2-cyclopentylphenyl)-3-methylpyridine (4d)
[0160]
[0161] Obtained using General procedure C employing 3-methyl-2-phenylpyridine (67.8 mg, 0.40 mmol) and bromocyclopentane (64.0 µL, 0.6 mmol). The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4d of 60%.Synthesis of (4-(3-methyl-2-(pyridin-2-yl)phenyl)piperidin-1-yl)(thiophen-2-yl)methanone (4e)
[0162]
[0163] Obtained using General procedure C employing 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol) and (4-bromopiperidin-1-yl)(thiophen-2-yl)methanone (120.0 mg, 0.44 mmol. The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4e of 92%.Synthesis of tert-butyl 4-(3-methyl-2-(pyridin-2-yl)phenyl)piperidine-1-carboxylate (4f)
[0164]
[0165] Obtained using General procedure C employing 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol) and (tert-butyl 4-bromopiperidine-1-carboxylate (132.0 mg, 0.50 mmol). The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4f of 92%.Synthesis of 2-(2-methyl-6-(tetrahydro-2H-pyran-4-yl)phenyl)pyridine (4g)
[0166]
[0167] Obtained using General procedure C employing 2-(o-tolyl)pyridine (64.0 µL, 0.40 mmol) and 4-bromotetrahydro-2H-pyran (47.4 µL, 0.42 mmol). The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4g of 88%.Synthesis of 2-(2-fluoro-6-(tetrahydro-2H-pyran-4-yl)phenyl)pyridine (4h)
[0168]
[0169] General Procedure C was applied. 2-(2-fluorophenyl)pyridine (69.2 mg, 0.40 mmol) and 4-bromotetrahydro-2H-pyran (47.4 µL, 0.42 mmol) were employed. The reaction was stirred at 50 °C for 24 hours. The crude mixture was purified by column chromatography eluting with 10% EtOAc in hexane to yield the title compound 4h (98.0 mg, 90%) as a colourless oil.
[0170] 1< H NMR (400 MHz, CDCl 3 ) δ 8.66 (d, J = 5.0 Hz, 1H), 7.70 (m, 1H), 7.34 - 7.15 (m, 3H), 7.11 (d, J = 7.9 Hz, 1H), 6.93 (m, 1H), 3.95-3.80 (m, 2H), 3.20-3.10 (t, J = 11.8 Hz, 2H), 2.75-2.60 (m, 1H), 1.80-1.65 (m, 2H), 1.63-1.50 (m, 2H).
[0171] 13< C NMR (101 MHz, CDCl 3 ) δ 13< C NMR (101 MHz, CDCl 3 ) δ 160.2 (d, J = 245.5 Hz), 154.3, 149.8, 146.8 (d, J = 2.0 Hz), 136.4, 130.1 (d, J = 8.8 Hz), 128.2 (d, J = 15.6 Hz), 125.9 (d, J= 2.0 Hz), 122.7, 122.1 (d, J = 3.4 Hz), 113.5 (d, J = 22.5 Hz), 68.5, 37.7 (d, J = 2.4 Hz), 33.9.
[0172] 19< F NMR (376 MHz, CDCl 3 ) δ -115.42.Synthesis of 2-(2-methyl-6-(tetrahydro-2H-pyran-4-yl)phenyl)pyrimidine (4i)
[0173]
[0174] General Procedure C was applied. 2-(2-methyl-6-(tetrahydro-2H-pyran-4-yl)phenyl)pyrimidine (68.0 mg, 0.40 mmol and 4-bromotetrahydro-2H-pyran (47.4 µL, 0.42 mmol) were employed. The reaction was stirred at 50 °C for 18 hours. The crude mixture was purified by column chromatography eluting with 50% EtOAc in hexane to yield the title compound 2i (82.3 mg, 81%) as a colourless solid.
[0175] 1< H NMR (400 MHz, CDCl 3 ) δ 8.83 (d, J = 5.0 Hz, 2H), 7.31 - 7.22 (m, 2H), 7.19 (d, J = 7.7 Hz, 1H), 7.09 (d, J= 7.3 Hz, 1H), 4.09 - 3.78 (m, 2H), 3.32 - 3.00 (m, 2H), 2.31 (tt, J= 11.9, 3.8 Hz, 1H), 1.98 (s, 3H), 1.87 - 1.70 (m, 2H), 1.72 - 1.54 (m, 2H).
[0176] 13< C NMR (101 MHz, CDCl 3 ) δ 168.7, 157.3, 143.1, 138.8, 135.7, 129.0, 128.3, 123.8, 119.3, 68.6, 38.8, 33.9, 20.2.Synthesis of [diazepam]-[4-bromotetrahydro-2H-pyran] (4j)
[0177]
[0178] General Procedure C was applied. Diazepam (85.4 µL, 0.30 mmol), 4-bromotetrahydro-2H-pyran (74.2 mg, 0.45 mmol), K 2 CO 3 (124.4 mg, 3 equiv) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol) were employed. The reaction was stirred in NMP (1 mL, 0.5 M with respect to the DG-containing arene) at 50 °C for 48 hours. The crude mixture was purified by column chromatography eluting with 65% EtOAc in hexane to yield the title compound 4j (35.0 mg, 34%) as a colourless oil.
[0179] 1< H NMR (500 MHz, CDCl 3 ) δ 7.44 - 7.34 (m, 2H), 7.31 - 7.15 (m, 4H), 6.97 (d, J = 2.6 Hz, 1H), 4.80 (d, J = 10.8 Hz, 1H), 3.97 - 3.67 (m, 3H), 3.42 (s, 3H), 3.11 (t, J = 11.7 Hz, 1H), 2.90 (t, J = 12.2 Hz, 1H), 2.33 (t, J = 12.1 Hz, 1H), 1.76 - 1.56 (m, 2H), 1.48 (d, J = 13.4 Hz, 1H), 1.06 (d, J = 13.4 Hz, 1H).
[0180] 13< C NMR (126 MHz, CDCl 3 ) δ 170.8, 169.8, 143.7, 141.3, 138.1, 132.1, 131.5, 130.1, 129.6, 129.4, 129.2, 126.8, 126.3, 122.3, 68.6, 68.3, 56.8, 38.4, 35.0, 33.9, 33.0.3-(4,5-diphenyloxazol-2-yl)-1-(4-(3-methyl-2-(pyridin-2-yl)phenyl)piperidin-1-yl)propan-1-one (4k) from oxaprozin derivative
[0181]
[0182] General Procedure C was applied. 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol) and 1-(4-bromopiperidin-1-yl)-3-(4,5-diphenyloxazol-2-yl)propan-1-one (194.0 mg, 0.44 mmol) were employed. The reaction was stirred at 50 °C for 48 hours. The crude mixture was purified by column chromatography eluting with 65% EtOAc in hexane to yield the title compound 4k (146.0 67%mg, 67%) as a colourless oil.
[0183] 1< H NMR (400 MHz, CDCl 3 ) δ 8.72 (d, J = 5.0 Hz, 1H), 7.78 - 7.73 (m, 1H), 7.63 - 7.58 (m, 2H), 7.57 - 7.52 (m, 2H), 7.39 - 7.27 (m, 7H), 7.25 (t, J = 7.7 Hz, 2H), 7.12 - 7.04 (m, 2H), 4.68 (d, J = 13.0 Hz, 1H), 3.96 - 3.87 (m, 1H), 3.34 - 3.09 (m, 2H), 3.04 - 2.68 (m, 3H), 2.49 - 2.21 (m, 2H), 2.00 (s, 3H), 1.93 - 1.75 (m, 1H), 1.75 - 1.46 (m, 3H).
[0184] 13< C NMR (101 MHz, CDCl 3 ) δ 169.3, 162.9, 159.7, 149.8, 145.4, 142.9, 140.0, 136.4, 136.2, 135.2, 132.7, 129.1, 128.7, 128.7, 128.5, 128.5, 128.2, 128.1, 128.1, 126.5, 124.7, 123.5, 122.0, 46.3, 42.7, 39.4, 33.8, 32.8, 30.1, 24.0, 20.6.Synthesis of [2-(2-fluorophenyl)pyridine]-[epiandrosterone] 4l
[0185]
[0186] Obtained by using General procedure C. 1d (34.6 mg, 0.20 mmol), 3α-21 (106 mg, 0.30 mmol), K 2 CO 3 (124.4 mg, 3 equiv) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol) were employed. The reaction was stirred at 50 °C for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 4l of 80%.General Procedure D: Ru-catalysed secondary alkylation of DG-containing arenes with primary alkyl bromides
[0187] General procedure for the primary alkylation of DG-containing arenes
[0188] All liquid reagents were degassed with at least 3 freeze-pump-thaw cycles prior to use. Tribasic potassium phosphate (K 3 PO 4 ) and potassium phenylphosphonate (PhP(O)O 2 K 2 ) were dried at 80 °C in a vacuum oven for at least 48 hours prior to use. Unless otherwise indicated, a 10 mL Schlenk tube was charged with ruthenium aqua catalyst 2 (28.4 mg, 0.04 mmol, 10 mol%), K 3 PO 4 (254.7 mg, 1.2 mmol, 3 equiv), and potassium phenylphosphonate (29.0 mg, 0.12 mmol, 30 mol), the appropriate DG-containing arene (0.40 mmol, 1 equiv) and the appropriate alkyl halide (1-2 equiv). After addition of the solids, 3 x 5 minute evac-refill cycles were performed before adding any liquid / oil reagents via injection along with the NMP (2 mL, 0.2 M with respect to the DG-containing arene). The reaction mixture was then stirred at 50 °C for 24 hours. Upon completion, the reaction mixture was diluted with water and washed with Et 2 O, before being dried over MgSO 4 , filtered, and concentrated in vacuo. The crude mixture was then loaded onto a silica gel column and purified using flash chromatography.
[0189] Reactions were performed as set out below following General Procedure D.
[0190] Data for all compounds following this procedure matches that previously reported by Larrosa et. al.
[0191] M. Wheatley, M. T. Findlay, R. López-Rodríguez, D. M. Cannas, M. Simonetti and I. Larrosa, Chem Catalysis, 2021, 1, 691-703. * NMR yield calculated by 1< H Q NMR using trimethoxy benzene as internal standard.Synthesis of 2-(2-methyl-6-octylphenyl)pyridine (5a)
[0192]
[0193] The reaction was carried out following General Procedure D with 2-(o-tolyl)pyridine (67.8 mg, 0.40 mmol) and 1-bromooctane (138.7.0 µL, 0.80 mmol) allowing the reaction mixture to stir for 72 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5a of 89%.Synthesis of 3-methyl-2-(2-octylphenyl)pyridine (5b)
[0194]
[0195] The reaction was carried out following General Procedure D with 3-methyl-2- phenylpyridine (67.8 mg, 0.40 mmol) and 1-bromooctane (138.7.0 µL, 0.80 mmol) stirring for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5b of 75%.Synthesis of (3-octyl-4-(pyridine-2-yl)phenyl)methanol (5c)
[0196]
[0197] The reaction was carried out following General Procedure D. (4-(pyridine-2-yl)phenyl)methanol (74.1 mg, 0.40 mmol) and 1-bromooctane (138.7.0 µL, 0.80 mmol) were used allowing the reaction mixture to stir for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5c of 51%.Synthesis of 2-(2-methyl-6-octylphenyl)pyrimidine (5d)
[0198]
[0199] The reaction was carried out following General Procedure D. 2-phenylpyrimidine (68.1 mg, 0.40 mmol) and 1-bromooctane (138.7.0 µL, 0.80 mmol) were used allowing the reaction mixture to stir for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5d of 72%.Synthesis of 3-methyl-2-(2-(3-phenylpropyl)phenyl)pyridine (5e)
[0200]
[0201] The reaction was carried out following General Procedure D, with the use of 3-methyl-2-phenylpyridine (67.8 mg, 0.40 mmol) and (3-bromopropyl)benzene (159.3 mg, 0.40 mmol). The crude reaction mixture was purified by column chromatography eluting with 0-10% EtOAc-DCM mixture (1:1) in hexane to give the named compound 5e (105.8 mg, 92%) as a colourless oil.
[0202] 1< H NMR (500 MHz, CDCl 3 ) δ 8.43 (d, J = 4.7 Hz, 1H), 7.47 (d, J = 7.8 Hz, 1H), 7.29 - 7.22 (m, 2H), 7.29 - 7.24 (m, 1H), 7.17 - 7.04 (m, 5H), 6.96 (d, J = 7.0 Hz, 2H), 2.50 - 2.45 (m, 4H), 2.02 (s, 3H), 1.77 - 1.61 (m, 2H).
[0203] 13< C NMR (126 MHz, CDCl 3 ) δ 159.5, 146.6, 142.2, 140.1, 140.0, 137.7, 131.5, 129.4, 128.9, 128.3, 128.2, 128.1, 125.9, 125.6, 122.2, 35.6, 32.6, 32.2, 19.3.Synthesis of tert-butyl 4-(2-(3-methylpyridin-2-yl)benzyl)piperidine-1-carboxylate (5f)
[0204]
[0205] The reaction was carried out following General Procedure D, with the use of 3-methyl-2-phenylpyridine (67.8 mg, 0.40 mmol) and tert-butyl 4-(bromomethyl)piperidine-1-carboxylate (222.5 mg, 0.80 mmol). The crude reaction mixture was purified by column chromatography eluting with 0-10% EtOAc-DCM mixture (1:1) in hexane to give the named compound 5f (108.5 mg, 74%) as a light yellow oil.
[0206] 1< H NMR (400 MHz, CDCl 3 ) δ 8.42 (dd, J = 4.8, 1.8 Hz, 1H), 7.50 (d, J = 7.7 Hz, 1H), 7.27 - 7.14 (m, 3H), 7.14 - 7.06 (m, 2H), 3.87 (s, 2H), 2.57 - 2.16 (m, 4H), 2.01 (s, 3H), 1.49 - 1.30 (s, 12H), 0.84 (qd, J = 12.5, 4.4 Hz, 2H).
[0207] 13< C NMR (126 MHz, CDCl 3 ) δ 159.5, 146.6, 142.2, 140.0, 137.7, 131.5, 129.4, 128.9, 128.3, 128.2, 128.1, 125.9, 125.6, 122.2, 35.6, 32.6, 32.2, 19.3.Synthesis of 2-(5-methoxy-2-octylphenyl)pyridine (5g)
[0208]
[0209] The reaction was carried out following General Procedure D, with the use of 2-(3-methoxyphenyl)pyridine (72.3 mg, 0.40 mmol) and 1-bromooctane (138.6 µL, 0.80 mmol). The crude reaction mixture was purified by column chromatography eluting with 0-10% EtOAc-DCM mixture (1:1) in hexane to give the named compound 5g (50.0 mg, 56%) as a colourless oil.
[0210] 1< H NMR (500 MHz, CDCl 3 ) δ 8.71 - 8.66 (m, 1H), 7.70 (app. Td, J = 7.6, 2.3 Hz, 1H), 7.30 - 7.18 (m, 3H), 6.91 - 6.87 (m, 1H), 6.79 (d, J = 8.2 Hz, 1H), 3.67 (s, 3H), 2.38 - 2.30 (m, 2H), 1.44 - 1.36 (m, 2H), 1.28 - 1.04 (m, 10H), 0.83 (t, J = 7.2 Hz, 3H).
[0211] 13< C NMR (126 MHz, CDCl 3 ) δ 157.1, 157.0, 149.3, 142.8, 135.7, 129.6, 128.9, 125.8, 121.7, 121.6, 108.3, 55.7, 33.0, 31.9, 31.0, 29.5, 29.2, 29.1, 22.7, 14.2.Synthesis of 1-(2-octylphenyl)ethan-1-one (5h)
[0212]
[0213] The reaction was carried out following General Procedure D, with the use of (E)-N,N-dimethyl-4-((1- phenylethylidene)amino)aniline (95.3 mg, 0.4 mmol) and 1-bromooctane (138.2 µL, 0.8 mmol) allowing the reaction mixture to stir for 72 hours. K 2 CO 3 (110.5 mg, 2 equiv) was used as the base and KOAc (11.8 mg, 30 mol%) as the additive. After 72 hours, HCl (aq. 3M, 2 mL) was added to the reaction mixture, and stirred for a further 1 hour, before being washed with ether. The crude reaction mixture was purified by column chromatography eluting with 0-5% EtOAc in hexane to give the named product 5h as a colourless oil (84.0 mg, 90%).
[0214] 1< H NMR (500 MHz, CDCl 3 ) δ 7.61 (dd, J= 8.3, 1.3 Hz, 1H), 7.38 (td, J = 7.2, 1.4 Hz, 1H), 7.28 - 7.21 (m, 2H), 2.87 - 2.79 (m, 2H), 2.57 (s, 3H), 1.61 - 1.50 (m, 2H), 1.40 - 1.21 (m, 10H), 0.94 - 0.80 (m, 3H).
[0215] 13< C NMR (101 MHz, CDCl 3 ) δ 202.3, 142.9, 138.1, 131.2, 131.1, 128.9, 125.6, 34.0, 31.9, 30.0, 29.8, 29.5, 29.3, 27.2, 22.7, 14.1.Synthesis of 1-(2-octylphenyl)-1H-pyrazole 5i
[0216]
[0217] The reaction was carried out following General Procedure D, with the use of 1-phenyl-1H-pyrazole (57.7 mg, 0.4 mmol) and 1-bromooctane (138.2 µL, 0.8 mmol) allowing the reaction to stir for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5i of 80%.Synthesis of 1-(2-octylphenyl)isoquinoline (5j)
[0218]
[0219] The reaction was carried out following General Procedure D, with the use of 1-phenylisoquinoline (82.1 mg, 0.4 mmol) and 1-bromooctane (138.2 µL, 0.8 mmol) allowing the reaction to stir for 24 hours. After this time, quantitative 1< H NMR using 1,3,5-trimethoxy benzene as internal standard indicated conversion to product 5j of 88%.Synthesis of [diazepam]-[n-octyl] (5k)
[0220]
[0221] The reaction was carried out following General Procedure D, with the use of diazepam (57.0 mg, 0.2 mmol), K 3 PO 4 (127.4 mg, 2 equiv), PhP(O)O 2 K 2 (14.3 mg, 30 mol%), [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol, 10 mol%) and 1-bromooctane (35.0 µL, 0.4 mmol). The crude reaction mixture was purified by column chromatography eluting with 0-30% EtOAc in hexane to give the named product 5k (37.1 mg, 47%) as a colourless oil.
[0222] 1< H NMR (500 MHz, CDCl 3 ) δ 7.47 - 7.42 (m, 1H), 7.37 - 7.30(m, 2H), 7.25 (d, J = 8.7 Hz, 2H), 7.18 (d, J = 7.8 Hz, 1H), 7.03 (d, J = 2.7 Hz, 1H), 4.83 (d, J = 10.8 Hz, 1H), 3.78 (d, J = 10.8 Hz, 1H), 3.41 (s, 3H), 2.37 - 2.26 (m, 1H), 2.20 - 2.06 (m, 1H), 1.38 - 0.92 (m, 12H), 0.83 (t, J = 7.1 Hz, 3H).
[0223] 13< C NMR (126 MHz, CDCl 3 ) δ 171.1, 169.8, 141.64, 141.3, 138.5, 132.0, 131.5, 130.1, 130.0, 129.9, 129.6, 129.3, 126.1, 122.5, 56.9, 35.0, 33.6, 31.9, 31.1, 29.9, 29.5, 29.3, 22.8, 14.2.(3S,8S,9S,10R,13R,14S,17R)-10,13-dimethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl 6-(2-(3-methylpyridin-2-yl)phenyl)hexanoate (5l) from cholesterol derivative
[0224]
[0225] The reaction was carried out following General Procedure D, with the use of 3-methyl-2-phenylpyridine (33.9 mg, 0.2 mmol), (3S,8S,9S,10R,13R,14S,17R)-10,13-dimethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1Hcyclopentala]phenanthren-3-yl 2-bromoacetate (225.5, 0.40 mmol), K 3 PO 4 (127.4 mg, 2 equiv), PhP(O)O 2 K 2 (14.3 mg, 30 mol%) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (14.2 mg, 0.02 mmol, 10 mol%). The crude reaction mixture was purified by column chromatography eluting with 0-10% EtOAc-DCM mixture (1:1) in hexane to give the named compound 5l (97.8 mg, 75%) as a light brown oil.
[0226] 1< H NMR (400 MHz, CDCl 3 ) δ 8.46 (dd, J = 4.8, 1.9 Hz, 1H), 7.54 (dd, J = 7.7, 1.8 Hz, 1H), 7.31 - 7.18 (m, 3H), 7.15 (dd, J = 7.7, 4.8 Hz, 1H), 7.13 - 7.08 (m, 1H), 5.33 (d, J = 4.9 Hz, 1H), 4.63 - 4.52 (m, 1H), 2.49 - 2.29 (m, 2H), 2.24 (d, J = 8.3 Hz, 2H), 2.12 (t, J = 7.6 Hz, 2H), 2.07 (s, 3H), 2.02 - 1.88 (m, 2H), 1.86 - 1.73 (m, 3H), 1.59 - 1.02 (m, 24H), 1.02 - 0.90 (m, 6H), 0.88 (d, J = 6.6 Hz, 3H), 0.83 (dd, J = 6.6, 1.8 Hz, 6H), 0.65 (s, 3H).
[0227] 13< C NMR (101 MHz, CDCl 3 ) δ 173.2, 159.7, 146.7, 140.2, 140.0, 139.8, 137.8, 131.6, 129.4, 128.8, 128.1, 125.8, 122.7, 122.3, 73.7, 56.8, 56.2, 50.1, 42.4, 39.8, 39.6, 38.3, 37.1, 36.7, 36.3, 35.9, 34.6, 32.8, 32.0, 32.0, 30.3, 28.9, 28.4, 28.1, 27.9, 24.8, 24.4, 23.9, 22.9, 22.7, 21.1, 19.4, 19.4, 18.8, 12.0.General Procedure E: Ru-catalysed methylation of DG-containing arenes with ammonium salt
[0228]
[0229] All liquid reagents were degassed with at least 3 freeze-pump-thaw cycles prior to use. To an oven-dried 10 mL Schlenk tube containing a magnetic stirring bar was added ruthenium aqua catalyst 2 (5 mol%, 0.015 mmol, 10.6 mg), NaI (89.9 mg, 2 equiv., 0.6 mmol), the methylating ammonium salt (1 equiv., 0.3 mmol, 56.0 mg), Na 2 CO 3 (31.8 mg, 1 equiv., 0.3 mmol,) and the DG-containing arene (1 equiv., 0.3 mmol) before performing 3 x 5 minute evac-refill cycles. NMP (1.5 mL, 0.2 M with respect to the DG-containing arene) was then added. The reaction mixture was stirred at 40 °C for 24 hours. Upon completion, the crude reaction mixture was diluted with water (30 mL) and extracted with Et 2 O (3 x 30 mL) before being loaded onto a silica gel column and purified by flash column chromatography under the conditions noted to afford pure product.
[0230] The following reactions were performed following General Procedure E:
[0231] Yields were calculated using 1< H QNMR with nitromethane as an internal standard. Isolated yields are given in brackets.Synthesis of 2-(2-methyl-5-(trifluoromethyl)phenyl)pyridine (6a)
[0232]
[0233] The title compound was synthesised as outlined in General Procedure E, using 2-(3-(trifluoromethyl)phenyl)pyridine (71.1 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol) for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6a of 98%.Synthesis of 2-(o-tolyl)pyridine (6b)
[0234]
[0235] The title compound was synthesised as outlined in General Procedure E, using 2-phenylpyridine (46.5 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol) for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6b of 75%.Synthesis of 3-methyl-2-(o-tolyl)pyridine (6c)
[0236]
[0237] The title compound was synthesised as outlined in General Procedure E, using 3-methyl-2-phenylpyridine (50.7 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol) for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6c of 80%.Synthesis of 1-(o-tolyl)isoquinoline (6d)
[0238]
[0239] The title compound was synthesised as outlined in General Procedure E, using 1-phenylisoquinolie (61.5 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol) for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6d of 82%.Synthesis of 2-(4-(tert-butyl)-2-methylphenyl)pyridine (6e)
[0240]
[0241] The title compound was synthesised as outlined in General Procedure E, using 2-(4-(tert-butyl)phenyl)pyridine (63 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol, 5 mol%). The reaction was allowed to stir for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6e of 72%. Purification using flash column chromatography eluting with 0-10% EtOAc in hexane afforded the named compound 6e as a yellow oil (43.2 mg, 64 %).
[0242] 1< H NMR (400 MHz, CDCl 3 ) δ 8.59 - 8.51 (m, 1H), 7.59 (td, J = 7.7, 1.8 Hz, 1H), 7.27 (m, 1H), 7.22 (d, J = 8.7 Hz, 1H), 7.17 (d, J = 2.8 Hz, 2H), 7.08 (m, 1H), 2.25 (s, 3H), 1.22 (s, 9H).
[0243] 13< C NMR (101 MHz, CDCl 3 ) δ 160.1, 151.2, 149.2, 137.7, 136.0, 135.2, 129.4, 127.8, 124.0, 122.9, 121.4, 34.5, 31.4, 20.6.Synthesis of 2-(2-fluoro-6-methylphenyl)pyridine (6f)
[0244]
[0245] The title compound was synthesised as outlined in General Procedure E, using 2-(2-fluorophenyl)pyridine (52 mg, 0.3 mmol and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol, 5 mol%). The reaction was allowed to stir for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6f of 88%. Purification using flash column chromatography eluting with 0-10% EtOAc in hexane afforded the named compound 6f as a yellow oil (33.7 mg, 73 %) 1< H NMR (400 MHz, CDCl 3 ) δ 8.73 (m, 1H), 7.76 (td, J = 7.7, 1.8 Hz, 1H), 7.40 - 7.32 (m, 1H), 7.32 - 7.19 (m, 2H), 7.07 (d, J = 7.6 Hz, 1H), 6.98 (t, J = 8.8 Hz, 1H), 2.21 (s, 3H).
[0246] 13< C NMR (101 MHz, CDCl 3 ) δ 160.2 (d, J = 245.0 Hz), 154.4, 149.6, 139.0 (d, J = 2.4 Hz), 136.2, 129.4 (d, J = 8.8 Hz), 128.4 (d, J = 15.2 Hz), 125.9 (d, J = 3.4 Hz), 125.5 (d, J = 2.4 Hz), 122.3, 113.0 (d, J = 22.5 Hz), 19.74 (d, J = 2.4 Hz).
[0247] 19< F NMR (376 MHz, CDCl 3 ) δ -117.15.(8R,9S,13S,14S)-13-methyl-17-oxo-7,8,9,11,12,13,14,15,16,17-decahydro-6H-cyclopenta[a]phenanthren-3-yl 4-methyl-3-(pyridin-2-yl)benzoate (6g) from estrone derivative
[0248]
[0249] The title compound was synthesised as outlined in General Procedure E, estrone derivative (135.5 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol, 5 mol%) were employed. The reaction was allowed to stir for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6g of 92%. Purification using flash column chromatography eluting with 15-25% EtOAc in hexane afforded the named compound 6g as a colourless oil (113.0 mg, 81%).
[0250] 1< H NMR (400 MHz, CDCl 3 ) δ 8.74 - 8.71 (m, 1H), 8.22 (d, J = 2.0 Hz, 1H), 8.11 (dd,J = 7.9, 2.0 Hz, 1H), 7.79 (td, J = 7.7, 1.8 Hz, 1H), 7.46 (dt, J = 7.8, 1.1 Hz, 1H), 7.42 (d, J = 7.9 Hz, 1H), 7.35 - 7.27 (m, 2H), 6.98 (dd, J = 8.8, 2.9 Hz, 1H), 6.94 (d, J = 2.6 Hz, 1H), 2.97 - 2.89 (m, 2H), 2.56 - 2.39 (m, 5H), 2.37 - 2.27 (m, 1H), 2.21- 1.94 (m, 4H), 1.70 -1.41 (m, 6H), 0.93 (s, 3H).
[0251] 13< C NMR (101 MHz, CDCl 3 ) δ 220.8, 165.3, 159.0, 149.4, 148.9, 142.3, 140.8, 138.1, 137.4, 136.4, 131.4, 131.2, 129.9, 127.4, 126.5, 124.3, 122.1, 121.8, 118.9, 50.5, 48.0, 44.2, 38.0, 35.9, 31.6, 29.5, 26.4, 25.8, 21.6, 20.7, 13.9.2,8-dimethyl-2-(4,8,12-trimethyltridecyl)chroman-7-yl-4-methyl-3-(pyridin-2-yl)benzoate (6h) from δ-tocopherol derivative
[0252]
[0253] The title compound was synthesised as outlined in General Procedure E, using the δ-tocopherol-DG-containing-derivative-arene (175.2 mg, 0.3 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (10.6 mg, 0.015 mmol, 5 mol%). The reaction was allowed to stir for 24 hours. After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 6h of 78%. Purification using flash column chromatography eluting with 0-10% EtOAc in hexane afforded the named compound as a colourless oil (90.7 mg, 56%).
[0254] 1< H NMR (400 MHz, CDCl3) δ 8.75 - 8.71 (m, 1H), 8.22 (d, J = 1.9 Hz, 1H), 8.11 (dd, J = 7.9, 1.9 Hz, 1H), 7.78 (td, J = 7.7, 1.8 Hz, 1H), 7.45 (dt, J = 7.8, 1.1 Hz, 1H), 7.41 (d, J = 8.0 Hz, 1H), 7.28 (ddd, J = 7.5, 4.9, 1.1 Hz, 1H), 6.81 (dd, J = 2.8, 0.9 Hz, 1H), 6.75 (d, J = 2.8 Hz, 1H), 2.82 - 2.69 (m, 2H), 2.46 (s, 3H), 2.18 (s, 3H), 1.89 - 1.69 (m, 2H), 1.67 - 0.99 (m, 24H), 0.87 (m, 12H).
[0255] 13< C NMR (101 MHz, CDCl3) δ 166.0, 159.3, 150.1, 149.6, 143.0, 142.4, 141.0, 136.7, 131.6, 131.4, 130.1, 128.0, 127.6, 124.4, 122.4, 121.6, 121.3, 119.5, 76.4, 40.4, 39.7, 37.8, 37.7 (2C), 37.6, 33.1, 33.0, 31.3, 28.3, 25.1, 24.8, 24.5, 23.0, 22.9, 22.8, 21.3, 20.9, 20.1, 20.0, 16.5.7-chloro-1-methyl-5-(o-tolyl)-1,3-dihydro-2H-benzo[e][1,4]diazepin-2-one (6i) from diazepam
[0256]
[0257] The title compound was synthesised as outlined in General Procedure E, using diazepam (57.0 mg, 0.2 mmol) and [Ru(OH 2 )(tBuCN) 5 ](BF 4 ) 2 2 (21.2 mg, 0.03 mmol, 10 mol%). After this time, quantitative 1< H NMR using nitromethane as internal standard indicated conversion to product 4i of 77%. Purification using flash column chromatography eluting with 25-35% EtOAc in hexane afforded the title product as a white solid (45.0 mg, 75 %).
[0258] 1< H NMR (400 MHz, CDCl 3 ) δ 7.47 (dd, J = 8.7, 2.5 Hz, 1H), 7.39 - 7.31 (m, 2H), 7.30 - 7.23 (m, 2H), 7.18 (d, J = 7.1 Hz, 1H), 7.05 (d, J = 2.6 Hz, 1H), 4.86 (d, J = 11.0 Hz, 1H), 3.81 (d, J = 11.0 Hz, 1H), 3.43 (s, 3H), 1.98 (s, 3H).
[0259] 13< C NMR (101 MHz, CDCl 3 ) δ 170.9, 170.0, 141.8, 138.8, 136.4, 131.9, 131.6, 131.5, 131.0, 129.9, 129.8, 129.1, 126.1, 122.7, 56.9, 34.9, 20.1.General Procedure F: Ru-catalysed meta-alkylation of DG-containing arenes with tertiary alkyl halides
[0260]
[0261] Each R 14< is independently a substituent, e.g. an optionally substituted C 1-12 alkyl group.
[0262] The blue light has a wavelength of 440 nm.General Procedure G: Ru-catalysed H / D exchange
[0263] General Procedure H: Oxidative alkene cleavage
[0264] ● = C atom of the cleaved C=C bond
[0265] Each R 15< is independently a substituent, e.g. an optionally substituted C 1-12 alkyl or optionally substituted aryl (e.g. phenyl) or heteroaryl and two or more R 15< groups may be linked to form a monocyclic or polycyclic ring.General Procedure I: Transfer hydrogenation
[0266]
[0267] Each R 16< is independently a substituent, e.g. an optionally substituted C 1-12 alkyl or optionally substituted aryl (e.g. phenyl) or heteroaryl.Intramolecular cyclisation
[0268] Compounds of Formula (I) may catalyse intramolecular cyclisation by reaction between a C-H of an sp 2< -hybridised aromatic or non-aromatic carbon atom and a primary, secondary or tertiary alkyl halide. Preferably, the cyclisation forms a 5- or 6-membered carbocyclic or heterocyclic ring.
[0269] An exemplary intramolecular cyclisation is: Alkene isomerisation
[0270] Compounds of Formula (I) may catalyse alkene isomerisation, for example: Alkene isomerisation
[0271] Compounds of Formula (I) may catalyse hydroalkynylation of an alkyne, for example: C(sp 3< )-H oxidation
[0272] Compounds of Formula (I) may catalyse oxidation by an oxidising agent of C-H to C-OH for a C-H group having an sp 3< -hybridised carbon atom, for example: C(sp 3< )-H amidation
[0273] Compounds of Formula (I) may catalyse intramolecular or intermolecular amidation of a C-H group having an sp 3< -hybridised carbon atom, for example: Air stability
[0274] The 1< H NMR spectrum of Ru complex 2 following several weeks of storage in an ambient environment is shown in Figure 1. No significant change in the spectrum or the visible appearance of this complex was observed upon air exposure. The ability of this complex to catalyse C-H bond to C-C bond conversion as described herein was unaffected by air exposure.
[0275] Figures 2A and 2B show the 1< H NMR spectra of Comparative Compound 1, illustrated below, before and after exposure to air. Significant differences in the spectra are apparent following air exposure, as can be seen from the stacked spectra of Figure 2C. The appearance of Comparative Compound 1 changed from an off white solid to a black solid upon exposure to the ambient environment. Attempts to convert a C-H bond to a C-C bond catalysed by Comparative Compound 1 after air exposure were unsuccessful.
[0276] Comparative Compound 1 is disclosed as "Ru9" in Simonetti, M., Cannas, D.M., Just-Baringo, X., Citorica-Yrezabal I.J. and Larossa I. "Cyclometallated ruthenium catalyst enables late-stage directed arylation of pharmaceuticals", Nature Chem 10, 724-731 (2018).
Claims
1. A compound of formula (I-A): wherein R1 in each occurrence is selected from H, optionally substituted C1-12 alkyl and optionally substituted C6-20 aryl; R2 in each occurrence is selected from optionally substituted C1-12 alkyl and optionally substituted C6-20 aryl; p' is 1 and q' is 5 or p' is 2 and q' is 4; p + q = 6; Y is an anion; and n is 1 or 2.
2. The compound according to claim 1 wherein p' is 1 and q' is 5.
3. The compound according to claim 1 or 2 wherein each R1 is H.
4. The compound according to any one of the preceding claims wherein n is 2, optionally wherein Y is a borate, phosphate or perchlorate anion.
5. A method of forming a compound according to any one of the preceding claims, the method comprising reducing a compound of formula RuZ3 in the presence of a compound of formula R2-CN to form an intermediate and reacting the intermediate with a compound of formula R12O, wherein Z is an anionic ligand and wherein the RuZ3 may be reduced by a reducing agent or RuZ3 may be reduced electrochemically.
6. The method according to claim 5 wherein Z is a halide.
7. The method according to claim 5 or 6 wherein the reducing agent is zinc.
8. A method of forming a compound according to any one of claims 1-4, the method comprising reacting a compound of formula RuZp'(NC-R2)q' wherein Z is an anionic ligand with a compound of formula R12O.
9. The method according to claim 8 wherein the reaction is performed the presence of a compound of formula M+Y- wherein M+ is a cation.
10. A method of forming a compound of formula (C), the method comprising a reaction according to Scheme 1: wherein (A) is a compound or a compound fragment; Ar1 is a monocyclic or fused aromatic or heteroaromatic ring which is unsubstituted or substituted with one or more substituents; DG is a directing group; X is a leaving group; R3 is a group comprising a carbon atom bound to which X is bound, and wherein the reaction is catalysed by a compound of formula (I): wherein R1 in each occurrence is selected from H, optionally substituted C1-12 alkyl and optionally substituted C6-20 aryl; R2 in each occurrence is selected from optionally substituted C1-12 alkyl and optionally substituted C6-20 aryl; p is at least 1; q is at least 1; p + q = 6; Y is an anion; and n is 1 or 2.
11. The method according to claim 10 according to Scheme 2:
12. The method according to claim 10 or 11 wherein: (a) the compound or compound fragment of formula (A) has formula (A-2) or (A-3): wherein R4-R7 are each independently H or a substituent, and R4 and R5 may be linked to form an optionally substituted monocyclic or fused ring, or (b) the compound or compound fragment of formula (A) has formula (A-4): wherein Ar2 is an optionally substituted moncyclic or fused heteroaromatic ring, or (c) the compound or compound fragment of formula (A) has formula (A-5) or (A-6): wherein R6 and R7 are each independently H or a substituent, and R6 and R7 may be linked to form an optionally substituted monocyclic or fused ring, or (d) the compound or compound fragment of formula (A) has formula (A-7): wherein Z1, Z2 and Z3 are each independently N or CR8 wherein R8 is H or a substituent.
13. The method according to claim 12 wherein Ar2 of the compound of formula (A-4) has C and N ring atoms and, optionally, O or S ring atoms.
14. The method according to any one of claims 11-13 wherein X is bound to an aromatic carbon atom of an aromatic or heteroaromatic ring of R3, wherein R3 may be an optionally substituted phenyl.
15. The method according to any one of claims 11-13 wherein X is bound to an sp3 hybridised primary or secondary carbon atom of R3, wherein R3 may be an optionally substituted C1-12 alkyl.