A novel carbanion-olefin intramolecular cyclization: synthesis of substituted 2-aroyl-3,4-dihydro-2H-benzopyrans from salicylaldehydes
摘要:
Utilization of a novel carbanion-olefin intramolecular 6-endo-trig cyclization reaction to provide 2-aroyl-3,4-dihydro-2H-benzopyrans is described. Through a sequence of a Wittig reaction, O-alkylation, and carbanion-olefin intramolecular cyclization, salicylaldehydes were converted into a series of new 2-aroyl-3,4-dihydro-2H-benzopyrans in two steps or in one-pot reaction. (C) 2009 Elsevier Ltd. All rights reserved.