Diels−Alder Reaction−Aromatization Approach toward Functionalized Ring C Allocolchicinoids. Enantioselective Total Synthesis of (−)-7<i>S</i>-Allocolchicine
作者:Andrei V. Vorogushin、Alexander V. Predeus、William D. Wulff、Hans-Jürgen Hansen
DOI:10.1021/jo034420t
日期:2003.7.1
reported for the synthesis of ring C functionalized allocolchicinoids, which is based on a Diels-Alder reaction-aromatization sequence. This route is complementary to the previously disclosed benzannulation approach involving Fischer carbene complexes and alkynes. Dienes 12 and 14 incorporate the natural substitution pattern on ring A and undergo Diels-Alderreactions with various dienophiles. Subsequent