The Invention of Radical Reactions. 32. Radical Deoxygenations, Dehalogenations, and Deaminations with Dialkyl Phosphites and Hypophosphorous Acid as Hydrogen Sources

Reagents, containing a P-H bond, such as dimethyl phosphite, diethyl phosphite, hypophosphorous acid and various salts of hypophosphorous acid are effective radical reducing agents for organic halides, thionoesters, and isocyanides affording high yields of the corresponding hydrocarbons. Reduction of tertiary phenyl selenides and tertiary nitro compounds are not efficient under these conditions. Olefination of 1,2-diols is also accomplished via the corresponding thiocarbonyl derivatives using hypophosphorous acid and triethylamine in the presence of a suitable “sacrificial olefin” in moderate to good yields.