The aldol reaction of seven-membered ketene silyl acetal (9) with cobalt-complexed propynals afforded the erythro isomer in a highly stereoselective manner, while the high threo selectivity could be realized with uncomplexed simple propynals.
七元酮
硅基
缩醛(9)与
钴络合的
丙炔醛发生醛醇反应,以高度立体选择性的方式得到赤式异构体,而与未络合的简单
丙炔醛发生醛醇反应,则可实现高度的赤式选择性。