Rhodium-catalyzed asymmetric anti-Markovnikov hydroformylation of α-substituted acrylates/acrylamides has been developed. By employing the Rh/(S,S)-DTBM-YanPhos complex, a series of β-chiral linear aldehydes were obtained in high yields (up to 94% yield) and high enantioselectivities (up to 96% ee). The utility of this methodology is demonstrated by a gram-scale reaction and a concise synthetic route
Process for preparing optically active 3-azidocarboxylic acid derivatives and 3-aminocarboxylic acid derivatives
申请人:Bohm Andreas
公开号:US20070149794A1
公开(公告)日:2007-06-28
A process for enantioselectively preparing 3-azidocarboxylic acid derivatives comprises reacting 3-sulfonatocarboxylic acid derivatives with an alkali metal azide in a solvent selected from the group comprising certain carboxamides; a solvent mixture which comprises such carboxamides; a solvent mixture of water and a solvent miscible homogeneously with water; water with the proviso that the addition of a phase transfer catalyst is not used in the reaction in water; and DMSO. The resulting products are optionally reduced to 3-aminocarboxylic acid derivatives.