在无溶剂条件下,三氟甲磺酸镓(III)催化环氧化物的开环可提供具有高区域选择性和化学选择性的β-羟基硫化物,产率高(84-97%)。另外,首次开发了在单一水中合成β-羟基亚砜的简单,有效且对环境无害的一锅法。通过H 2 O 2 -Ga(OTf)3系统的促进,该过程以高收率(81-94%)和高化学选择性提供了β-羟基亚砜,而没有检测到对β-羟基砜的过度氧化。反应后催化剂可以容易地回收并重新使用而没有明显的活性损失。
ZnCl2 (5 mol%) is an efficient catalyst for the thiolysis of 1,2-epoxides by thiophenol in water at pH 4.0. A variety of β-hydroxy phenylsulfides were obtained in short reaction times and excellent yields. Starting from cyclohexene oxide (1), two one-pot multi-step procedures in sole water (thiolysis/oxidation with H2O2) have been realized, for the chemoselective synthesis of the corresponding β-hydroxysulfoxides 19 or for the related β-hydroxysulfone 20.