Cyclodextrin acts as a restricting nanovessel to enhance regioselectivity in bromination of substituted phenols such as 3-nitrophenol, 2-chlorophenol, 3-chlorophenol, and 4-chlorophenol. In contrast to solution bromination, cyclodextrin facilitates regioselectivemonobromination and formation of polybrominated products are substantially reduced. Selectivities in brominations are also observed in water
环糊精充当限制性纳米容器,以增强取代酚(例如3-硝基苯酚,2-氯苯酚,3-氯苯酚和4-氯苯酚)的溴化反应中的区域选择性。与溶液溴化相反,环糊精促进区域选择性单溴化,多溴化产物的形成大大减少。在水中和固态下也观察到溴化反应的选择性。观察到的结果是根据环糊精腔内取代酚的特定包容模式进行合理化的,并从能量最小化研究和1 H– 1 H NOESY中获得了有力的支持。
CCCIX.—The replacement of bromine in bromophenols by the nitro-group. Part I. 2 : 4 : 6-Tribromo-3-nitrophenol and -3-chlorophenol. Some cases of group migration