The reaction of (Z)- or (E)-1,2-bis(phenylsulfanyl)ethene (1) with an excess of lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 2.5 mol%) in the presence of a carbonyl compound as electrophile (Barbier conditions) in THF at −78 °C leads, after hydrolysis with water at temperatures ranging between −78 °C and rt, to a mixture of the corresponding (Z/E)-unsaturated 1,4-diols 2, the
(Z)-或(E)-1,2-双(
苯硫基)
乙烯(1)与过量的
锂和催化量的4,4'-二叔丁基
联苯(DT
BB,2.5 mol% )在-78°C的温度下用
水水解后,在-78°C的THF中存在亲电的羰基化合物(Barbier条件)的情况下,导致相应的(Z / E)-不饱和1,4
-二醇2,非对映异构体比例与起始原料的立体
化学无关。
烯丙醇3是整个过程中某些
锂化
中间体上的
锂-
氢交换产生的主要副产物。给出了对所观察到的行为的机械解释。