Nafion-H-catalyzed Mukaiyama aldol condensations and hetero Diels–Alder reactions using aldehydes and imines. Part 15: General synthetic methods
摘要:
Nafion-H catalyzes the Mukaiyama aldol condensation between aromatic aldehydes and the Danishefsky diene whereas the corresponding imines directly undergo hetero Diels-Alder cyclization to form 2,3-dihydro-gamma -pyridones. Some chiral acetal derived aldehydes were round to undergo Mukaiyama aldol condensation in the presence of Lewis acids but not with Nafion-H. (C) 2001 Elsevier Science Ltd. All rights reserved.