Conversion of Epoxides to 1,3-Dioxolanes Catalyzed by Tin(II) Chloride
摘要:
Anhydrous tin(II) chloride is an efficient catalyst for the reaction of epoxides with acetone to prepare 2,2-dimethyl-1,3-dioxolanes (acetonides) in good to excellent yields. Mono-, di-, and trisubstituted epoxides participate equally well in this diastereospecific reaction. The use of single enantiomer epoxides under the reported conditions results in significant erosion of optical activity.
The readily prepared 2,4-bisperfluorooctylphenyl butylselenide catalyzes the epoxidation of various olefins with hydrogen peroxide in a fluorous biphasic system. The catalyst is selectively soluble in perfluorinated solvents and can easily be recovered simply by phase separation. Furthermore, the catalyst can be reused several times without a decrease of yield and an increase of reaction time.
In the presence of a catalytic amount of dioxo(tetramesitylporphyrinato)ruthenium(VI) complex, nitrousoxide (N2O) oxidized trisubstituted olefins into the corresponding epoxides in good-to-high yields with high selectivities.
Dinitrogen oxide was employed as a clean oxidant for various oxidations in the presence of a catalytic amount of dioxoruthenium tetramesitylporphyrin complex (Ru(tmo)(O) 2 ). A variety of olefins, secondary alcohols, and benzyl alcohols were smoothly oxidized to the corresponding epoxides, ketones, and aldehydes in high yields. In the oxidation of 9,10-dihydroanthracene derivatives, the competitive
Conversion of Epoxides to 1,3-Dioxolanes Catalyzed by Tin(II) Chloride
作者:James R. Vyvyan、Jennifer A. Meyer、Korin D. Meyer
DOI:10.1021/jo035112y
日期:2003.11.1
Anhydrous tin(II) chloride is an efficient catalyst for the reaction of epoxides with acetone to prepare 2,2-dimethyl-1,3-dioxolanes (acetonides) in good to excellent yields. Mono-, di-, and trisubstituted epoxides participate equally well in this diastereospecific reaction. The use of single enantiomer epoxides under the reported conditions results in significant erosion of optical activity.