Intramolecular Diels??Alder Reaction with Furan??Diene. 1. A Novel Entry to the BCD??Ring System of 11??Ketosteroids

LA Van Royen, R Mijngheer…

文献索引：Royen, Luc A. Van; Mijngheer, Roelant; Clercq, Pierre J. De Bulletin des Societes Chimiques Belges, 1984 , vol. 93, # 11 p. 1019 - 1036

全文：HTML全文

被引用次数: 23

摘要

Abstract A novel approach for the synthesis of the BCD-ring system in steroids is described. The sequence centers about the intramolecular Diels-Alder reaction of furan 15, which, depending on the reaction conditions, leads predominantly to adduct 26 (kinetic control) or 27 (thermodynamic control). The precursor 15 is obtained from enol ether 2, prepared via dissolved metal reduction of 5. Only in reduced adduct 34 is the oxygen bridge opened ...