Asymmetric weitz - scheffer epoxidation promoted by bovine serum albumin
作者:Stefano Colona、Nicoletta Gaggero、Amedea Manfredil、Massimo Spadoni、Luigi Casella、Giacomo Carrea、Piero Pasta
DOI:10.1016/s0040-4020(01)86023-3
日期:1988.1
The epoxidation of 2-substituted naphthoquinones with t-BuOOH in an aqueous buffer solution containing a small amount (up to 5 % molar equiv) of bovine serum albumin (BSA) gives the corresponding epoxides with enantiomeric excess (e.e.) up to 100 %. The enantioselectivity is very sensitive to the addition of water miscible or immiscible cosolvents and to the length of the alkyl chain in position 2
Tetrabutylammonium Iodide Catalyzed Epoxidation of Naphthoquinone Derivatives with tert-Butyl Hydroperoxide as an Oxidant
作者:Bai-Ru Ai、Xu-Ling Chen、Yu Dong、Lei Tang、Ji-Yu Wang
DOI:10.1055/s-0036-1589035
日期:2017.9
reaction time, and broad substrate scope An efficient and environmentally benign procedure has been developed for the epoxidation of naphthoquinone derivatives by using tetrabutylammonium iodide as a catalyst and tert-butyl hydroperoxide as an oxidant in the presence of silicon dioxide. This protocol, which provides a facile base-free methodology for the synthesis of some new naphthoquinone-based epoxides