Regioselective Diels–Alder addition to 2-benzopyran-3-ones; a route to aromatic steroids
作者:David A. Bleasdale、David W. Jones
DOI:10.1039/c39850001027
日期:——
2-Benzopyran-3-one (1; X = H) undergoes strongly regioselective Diels–Alder additions to buta-1,3-diene, isobutene, but-1-ene, and the olefin (6); the adducts derived from (6) and either (1; X = H) or (1; X = OMe) are readily transformed into the aromatic steroids: (9), (10), (17), (18), 9-epi-(10), 9-epi-(18), the naphthalene (14), and the dihydronaphthalene (15).
2-苯并吡喃-3-酮(1; X = H)在丁1,3-二烯,异丁烯,丁1-烯和烯烃中具有强烈的区域选择性Diels-Alder加成反应(6);由(6)和(1 ; X = H)或(1 ; X = OMe)衍生的加合物很容易转化为芳族类固醇:(9),(10),(17),(18),9- epi-(10),9- epi-(18),萘(14)和二氢萘(15)。