C2-Symmetric Pyrrolidine-Based Chiral Ammonium Salts as a Phase-Transfer Catalyst
摘要:
Chiral pyrrolidinium salts having substituents at the alpha, alpha' positions were synthesized to develop a chiral phase-transfer catalyst which have more simplified structure. The catalytic function of these synthesized catalysts was evaluated using asymmetric benzylation of N-(diphenylmethylene)glycine tert-butyl ester, and alpha,alpha'-disubstituded pyrrolidinium salts having an alkyl chain with a hydroxyl group at a chiral center were found to afford moderate enantioselectivity.