Traceless Silylation of β-C(sp~3)-H Bonds of Alcohols via Perfluorinated Acetals

摘要

We report the silylation of primary C–H bonds located β to secondary and tertiary alcohols by exploiting perfluorinated esters as traceless directing groups. The conversion of a secondary or tertiary alcohol to a perfluoroalkyl ester and conversion of the ester to the corresponding silyl acetals by hydrosilylation allows for selective β-C(sp~(3))–H silylation catalyzed by the combination of [Ir(cod)OMe]_(2) and Me_(4)Phen (3,4,7,8-tetramethyl-1,10-phenanthroline) to form 6-membered dioxasilinane. Tamao-Fleming oxidation of these dioxasilinane leads to 1,2 diols. The developed sequence was applied to a series of natural products containing hydroxyl groups.