Direct vinylogous aldol addition of γ-butyrolactones and γ-butyrolactams
摘要:
Deprotonation of N-benzyl-3-phenylselenylpyrrol-2(5H)-one 3 and furan-2(5H)-one 4 and reaction with aldehydes affords regioselectively 5-(1'-hydroxy)-gamma-butyrolactones and the aza-analogous butyrolactams with good diastereoisomeric excesses. The presence of Lewis acids enhances the diastereoisomeric ratios.This methodology is an alternative to Lewis acid mediated silyloxydiene condensation. (C) 2000 Elsevier Science Ltd. All rights reserved.
Direct vinylogous aldol addition of γ-butyrolactones and γ-butyrolactams
摘要:
Deprotonation of N-benzyl-3-phenylselenylpyrrol-2(5H)-one 3 and furan-2(5H)-one 4 and reaction with aldehydes affords regioselectively 5-(1'-hydroxy)-gamma-butyrolactones and the aza-analogous butyrolactams with good diastereoisomeric excesses. The presence of Lewis acids enhances the diastereoisomeric ratios.This methodology is an alternative to Lewis acid mediated silyloxydiene condensation. (C) 2000 Elsevier Science Ltd. All rights reserved.
Deprotonation of N-benzyl-3-phenylselenylpyrrol-2(5H)-one 3 and furan-2(5H)-one 4 and reaction with aldehydes affords regioselectively 5-(1'-hydroxy)-gamma-butyrolactones and the aza-analogous butyrolactams with good diastereoisomeric excesses. The presence of Lewis acids enhances the diastereoisomeric ratios.This methodology is an alternative to Lewis acid mediated silyloxydiene condensation. (C) 2000 Elsevier Science Ltd. All rights reserved.