135517-12-3Relevant articles and documents
Catalytic, asymmetric, and stereodivergent synthesis of non-symmetric β,β-Diaryl-α-Amino Acids
Molinaro, Carmela,Scott, Jeremy P.,Shevlin, Michael,Wise, Christopher,Mnard, Alain,Gibb, Andrew,Junker, Ellyn M.,Lieberman, David
, p. 999 - 1006 (2015/01/30)
We report a concise, enantio- and diastereoselective route to novel nonsymmetrically substituted N-protected β,β-diaryl-α-amino acids and esters, through the asymmetric hydrogenation of tetrasubstituted olefins, some of the most challenging examples in the field. Stereoselective generation of an E- or Z-enol tosylate, when combined with stereoretentive Suzuki-Miyaura cross-coupling and enantioselective hydrogenation catalyzed by (NBD)2RhBF4 and a Josiphos ligand, allows for full control over the two vicinal stereogenic centers. High yields and excellent enantioselectivities (up to 99% ee) were obtained for a variety of N-acetyl, N-methoxycarbonyl, and N-Boc β,β-diaryldehydroamino acids, containing a diverse and previously unreported series of heterocyclic and aryl substituted groups (24 examples) and allowing access to all four stereoisomers of these valuable building blocks.
