Studies in Sigmatropic Rearrangement: Synthesis of a [6,6]Pyranothiopyran Ring System by Sequential Claisen Rearrangement and Pyridine Hydrotribromide Mediated Regioselective “6-Endo” Cyclization
作者:K. C. Majumdar、U. K. Kundu、S. K. Ghosh
DOI:10.1021/ol020088g
日期:2002.8.1
afford 4-aryloxymethylthiopyrano[3,2-c][1]benzopyran-5(2H)-ones which are subsequently subjected to heating in o-dichlorobenzene in the presence of N,N-diethylaniline and then treated with pyridinehydrotribromide to give [6,6]pyranothiopyrans in almost quantitative yield.