Binaphthyls nickel catalysts

The other primary application of asymmetric Grignard coupling reactions has been in the synthesis of axially chiral binaphthyl and biphenyl derivatives. Hayashi performed a binaphthyl synthesis (equation 6) in 95% ee using a nickel catalyst and ligand (7), a P-O chelating analog to (3). For a similar synthesis of chiral biaryls (equation 7) ligand, (8) was found to yield the most successful results (93% ee). ... 

Unsymmetrical binaphthyls were synthesized by photochemically stimulated reaction of naphthyl iodides with naphthoxide ions in an SrnI reaction. " Methyl chloroacetate coupled with aryl iodides under electrolysis conditions, using a nickel catalyst. " " Unsymmetrical biaryls were prepared from two aryl iodides using a Cul catalyst and microwave irradiation. " ... 

Hayashi T, Hayashizaki K, Kiyoi T, Ito Y. Asymmetric synthesis catalyzed by chiral ferrocenylphosphine-transition-metal complexes. 6. Practical asymmetric synthesis of 1,1 -binaphthyls via asymmetric cross-coupling with a chiral [(alkoxyalkyl)ferrocenyl] monophosphine/nickel catalyst. J. Am. Chem. Soc. 1988 110(24) 8153-8156. 

Vinylogous Mukaiyama-Michael additions of 2-trimethylsilyloxyfuran to 3-alkenoyl-2-oxazolidinones to provide 7-butenolides were shown to be /7-selective. The reaction could be rendered enantioselective in the presence of a (T symmetric copper-bisoxazoline complex <1997T17015, 1997SL568> or a l,T-binaphthyl-2,2 -diamine-nickel(ii) complex as catalyst, as depicted in Equation (16) <2004CC1414>. 

Optically active l,l -binaphthols are among the most important chiral ligands of a variety of metal species. Binaphthol-aluminum complexes have been used as chiral Lewis acid catalysts. The l,T-binaphthyl-based chiral ligands owe their success in a variety of asymmetric reactions to the chiral cavity they create around the metal center [107,108]. In contrast with the wide use of these binaphthyls, the polymer-supported variety has been less popular. The optically active and sterically regular poly(l,l -bi-naphthyls) 96 have been prepared by nickel-catalyzed dehalogenating polycondensation of dibromide monomer 95 (Sch. 7) [109] and used to prepare the polybinaphthyl aluminum(III) catalyst 97 this had much greater catalytic activity than the corresponding monomeric catalyst when used in the Mukaiyama aldol reaction (Eq. 29). Unfortunately no enantioselectivity was observed in the aldol reaction. 

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