The synthesis of (S)-(+)-pantolactone and its analogues from an ephedrine-derived morpholinone
摘要:
An efficient general route for the enantioselective synthesis of (S)-(+)-pantolactone and its analogues has been developed from an ephedrine-derived chiral morpholin-3-one. Selective dialkylation of an ephedrine-derived chiral template without epimerization is the key step in this synthesis. (C) 2004 Elsevier Ltd. All rights reserved.
Kinetic Resolution of Racemic 2-Hydroxy-γ-butyrolactones by Asymmetric Esterification Using Diphenylacetic Acid with Pivalic Anhydride and a Chiral Acyl-Transfer Catalyst
Various optically active 2-hydroxy-γ-butyrolactone derivatives are produced via the kineticresolution of racemic 2-hydroxy-γ-butyrolactones with diphenylacetic acid using pivalic anhydride and (R)-benzotetramisole ((R)-BTM), a chiral acyl-transfer catalyst. Importantly, the substrate scope of this novel protocol is fairly broad (12 examples, s-value; up to over 1000). In addition, we succeeded in