摘要:
[GRAPHICS]Enolates of a new camphor-derived lactam auxiliary are shown to monoalkylate with very high diastereoselectivity. A second alkylation occurs with reactive alkylating agents to afford quaternary centers also with high diastereoselectivity, In accord with a proposed model for diastereoselection, lithium and sodium enolates provide products with an opposite sense of asymmetric induction.