Enantioselective synthesis of naphthopyran derivatives catalyzed by bifunctional thiourea-tertiary amines
摘要:
An efficient bifunctional thiourea catalyzed addition-cyclization reaction of 2-naphthol with alpha,alpha-dicyanoolefins is realized under mild conditions to afford the corresponding naphthopyran derivatives in high yields and moderate enantioselectivities. Additionally, the development of an asymmetric three-component one-pot procedure for the synthesis of naphthopyran derivatives is also reported. (c) 2008 Elsevier Ltd. All rights reserved.