Protection of Alcohols through Radical Coupling

A variety of alcohols can be readily protected with the 2-tetrahydrofuranyl group by using bis(tetra-n-butylammonium) peroxydisulfate (1) in THF.^1a) This is accomplished through the coupling of a 2-tetrahydrofuranyl radical with an alkoxy radical, under nearly neutral conditions. Therefore, 1 permits the protection of alcohols containing functional groups such as olefins, sulfides, acetals, etc.

Similarly, when tetrahydropyran is used, hydroxyl groups are protected with the 2-tetrahydropyranyl group.^1b)