On the Diels−Alder Reaction of Allenes Bearing a Diphenylphosphoryl or (Trichloromethyl)sulfonyl Substituent
作者:Frank Scheufler、Martin E. Maier
DOI:10.1002/1099-0690(200012)2000:23<3945::aid-ejoc3945>3.0.co;2-6
日期:2000.12
Diels−Alder reactions of two allenes, diphenyl(1,2-propadienyl)phosphane oxide (4) and 1,2-propadienyltrichloromethyl sulfone (7), with cyclic dienes were studied. While 4 only reacted with cyclopentadiene, to provide the endo adduct 5, the allene 7 proved to be much more reactive. Thus, the cycloaddition between 7 and N-Boc-pyrrole gave a mixture of the endo and exo adducts 9. The observed reactivities
研究了两个异戊烯,二苯基(1,2-丙二烯基)膦氧化物(4)和1,2-丙二烯基三氯甲基砜(7)与环状二烯的狄尔斯-阿尔德反应。尽管4仅与环戊二烯反应以提供内加合物5,但事实证明丙二烯7具有更高的反应性。因此,在7和N -Boc-吡咯之间的环加成反应生成了内加合物和外加合物9的混合物。可以通过半经验MO计算合理化观察到的反应性。