Regio- and stereoselectivity in reactions of gem-difluorinated vinyloxiranes with heteronucleophiles were successfully controlled. Halogen atoms were introduced regioselectively at the allylic epoxide carbon with an inversion in stereochemistry using MgBr2·Et2O or Li2CuCl4 to produce anti-vic-halohydrine. The other diastereomers were obtained selectively using LiBr/AcOH or BCl3, and SN2‘ type products
宝石-二
氟乙烯基环氧乙烷与杂多亲核试剂反应的区域选择性和立体选择性已得到成功控制。卤原子物在使用MgBr在立体
化学的反转烯丙基环氧碳区域选择性地引入2 ·的Et 2 O或栗2的CuCl 4,以产生抗- VIC -halohydrine。使用LiBr / AcOH或BCl 3选择性地获得其他非对映异构体,并且通过改变反应温度以优异的E偏爱选择性地形成S N 2'型产物。此外,进一步的研究使我们发现区域和立体选择性S几种布朗斯台德酸的N 2'加入取决于酸的p K a值。在强酸性条件下,我们完全获得Ë
烯丙醇。