Lewis base catalysis proved to be more efficient, and the highest asymmetric induction for allylation of ortho-fluorobenzaldehyde reached 82 % ee, which is comparable to other used catalytic conditions. In cases of ortho-vinylbenzaldehyde, the Keck allylation provided the product in 88 % ee. An enantioenriched homoallylicalcohol was used as the starting material for the synthesis of a sertraline
我们报告了在路易斯碱(N,N-二氧化物)、路易斯酸(凯克烯丙基化)和布朗斯台德酸催化下邻位取代苯甲醛烯丙基化的系统研究。邻-卤代苯甲醛被用作醛底物,并特别关注邻-乙烯基和炔基苯甲醛,它们可能作为有趣的合成子用于制备更复杂的手性化合物。在催化条件下实现了类似的对映选择性。在邻卤苯甲醛的情况下,路易斯碱催化被证明更有效,邻氟苯甲醛烯丙基化的最高不对称诱导达到 82% ee,与其他使用的催化条件相当。在邻乙烯基苯甲醛的情况下,Keck 烯丙基化提供 88% ee 的产物。
Silver-Catalyzed, Manganese-Mediated Allylation and Benzylation Reactions of Aldehydes and Ketones