Tungsten-, Molybdenum-, and Cerium-Promoted Regioselective and Stereospecific Halogenation of 2,3-Epoxy Alcohols and 2,3-Epoxy Sulfonamides
摘要:
The first catalytic regioselective and stereospecific halogenation of 2,3-epoxy alcohols and 2,3-epoxy sulfonamides has been developed. Under the catalysis of commercially available W- or Mo-salts, complemented by the method using cerium halides, the C-3 selective ring opening of structurally diverse epoxides with Cl-, Br-, and I-nucleophiles afforded various halohydrins in good yields and high regioselectivities.
Asymmetric, Regioselective Bromohydroxylation of 2-Aryl-2-propen-1-ols Catalyzed by Quinine-Derived Catalysts
作者:Ye Zhang、Hui Xing、Weiqing Xie、Xiaolong Wan、Yisheng Lai、Dawei Ma
DOI:10.1002/adsc.201200782
日期:2013.1.14
The asymmetricbromohydroxylation of 2‐aryl‐2‐propen‐1‐ols catalyzed by quinine‐derived bifunctional catalyst has been developed. The regioselectivity was controlled by employing a boronate ester as tether which was formed in situ and enantioselectivity was introduced by taking advantage of a quinine‐derived bifunctional catalyst which activated the boronate ester and N‐bromosuccinimide (NBS) at the