Nonhomogeneous Phase Effect on the Generation of Carbene Radical Anions in the Birch-Type Reduction of Bis(gem-dihalocyclopropyl) Compounds

Article abstract of DOI:10.1021/jo00152a047

The reduction of 1,2-bis(gem-dichlorocyclopropyl)ethane (5) with sodium metal (4 molar equiv with respect to 5) in a mixed solution of NH3-THF-EtOH, which separated a metallic liquid phase on mixing, gave the parent hydrocarbon product predominantly.On the other hand, analogous reduction of 5 with lithium metal, which produced a homogeneous colored solution, predominantly gave the di- and trichloro intermediate products.The unusual results of the reduction with a nonhomogeneous reductant mixture are explained in terms of a rapid and consecutive electron transfer tothe molecule which is taken into or located in the vicinity of the reductant phase. 3,3,8,8-Tetrachlorotricyclo<5.1.0.0^2,4>octane behaved analogously.