Enantioselective synthesis of -amino acid

New optically active bis-quaternary ammonium salts were synthesized and applied to catalytic asymmtric alkylation of tert-butyl glycinate benzophenone Schiff base to provide a chiral α-amino acid derivative with 54% ee.

3p giesumanh 13-11-2018 22 1   Download

Phase-transfer-catalyzed alkylation of glycinate Schiff base with racemic secondary alkyl halides proceeded with excellent levels of synand enantioselectivities under the influence of a chiral quaternary ammonium bromide and 18- crown-6. The alkylation product can be selectively converted to the corresponding anti isomer, allowing the preparation of all the stereoisomers of β-alkyl-α-amino acid derivatives.

12p heoxinhkute 19-07-2010 81 5   Download