Regioselective Synthesis of 3‐(Aryloxyacetyl)‐2,3‐dihydrothieno[2,3‐b][1]benzothiopyran‐4‐ones via Tandem Cyclization
摘要:
2-[4-Aryloxybut-2-ynylthio][1]benzothiopyran-4-ones on treatment with m-chloroperoxy benzoic acid in chloroform at 0degreesC to room temperature afforded 3-(aryloxyacetyl)-2,3-dihydrothieno[2,3-b]benzothiopyrans in 65-70% yield. The sigmatropic [2,3] followed by [3,3] rearrangement, are attributed to this transformation.
STUDIES IN SIGMATROPIC REARRANGEMENT: REGIOSELECTIVE SYNTHESIS OF THIENO[2,3-<i>b</i>]- THIOCHROMEN-4-ONE DERIVATIVES
作者:K. C. Majumdar、S. K. Ghosh
DOI:10.1081/scc-120003620
日期:2002.1
Thermal rearrangement of a number of 2-(4'-aryloxybut-2'-ynylthio)-thiochromen-4-ones in refluxing chlorobenzene in the presence of catalytic amounts of 4-toluenesulfonic acid afforded 3-aryloxymethyl-2-methylthieno[2,3-b]thiochromen-4-ones in 55-62% yields.