The invention of new radical chain reactions. Part 11. A new method for the generation of tertiary radicals from tertiary alcohols

Abstract

A convenient procedure for the radical deoxygenation of tertiary alcohols has been invented using the double half esters of oxalic acid with the t-alcohol and N-hydroxypyridine-2-thione. Decomposition of this type of ester in the presence of 1,1-dimethylethane- or (better) 1,1-diethylpropane-thiol gave the corresponding hydrocarbons in good yield. It has been shown that the oxalate fragmentation is not concerted, but involves a stepwise loss of carbon dioxide. Tertiary alcohols are also a convenient source of radicals for addition to suitable alkenes with formation of quaternary centres.