undertaken. The reactions proceeded with high enantio- and diastereoselectivities with slightly better asymmetric induction observed in the case of N,N′-dioxide catalysis. The formed enantioenriched chiral unsaturated haloalcohols could be considered general building blocks, as they could be used in the syntheses of more complex natural products possessing substituted 1,3-diene fragments. This was exemplified
对路易斯碱(手性 N,N'-二氧化物)和布朗斯台德酸(手性
磷酸)对 (E)- 和 (Z)-卤代
丙烯醛的催化烯丙基化和
巴豆化进行了比较研究。反应以高对映选择性和非对映选择性进行,在 N,N'-二氧化物催化的情况下观察到稍好的不对称诱导。形成的富含对映体的手性不饱和卤代醇可以被认为是一般的构建单元,因为它们可以用于合成更复杂的具有取代 1,3-二烯片段的
天然产物。蝶呤酮和抗霉毒素的正式全合成就是例证。