The deoxygenation of secondary alcohols via thionoesters with the use of 5,10-dihydrosilanthrene as the radical reducing agent has been studied in detail. The ability of hydrogen donation of this silane has been measured using the one-carbon ring expansion of 1-(2-oxocyclopentyl)ethyl radical as a timing device.

A number of nucleoside substrates has been reduced under free radical conditions with tris(trimethylsilyl)silane. In one case a novel type of a $\beta$-(acyloxy)alkyl radical rearrangement has been observed, which leads through the generation of a C-1' radical species to the stereoselective preparation of an $\alpha$-ribonucleoside. The rate of the above 1,2-migration has been estimated, and a comparison with previously reported results has been made.

A number of nucleoside substrates has been reduced under free radical conditions with tris(trimethylsilyl)silane. In one case a novel type of a beta-(acyloxy)alkyl radical rearrangement has been observed, which leads through the generation of a C-1' radical species to the stereoselective preparation of an alpha-ribonucleoside. The rate of the above 12-migration has been estimated, and a comparison with previously reported results has been made.