TITANIUM(II) PORPHYRIN COMPLEXES - VERSATILE ONE-ELECTRON AND 2-ELECTRON REDUCING AGENTS - REDUCTION OF ORGANIC CHLORIDES, EPOXIDES, AND SULFOXIDES

Treatment of the well-defined complexes (TTP)Ti(eta(2)-EtC=CEt) or tra ns-(TTP)Ti(THF)(2) with vicinal dichloroalkanes or dichloroalkenes res ults in the production of alkenes or alkynes and 2 equiv of (TTP)TiCl. This net two-electron redox reaction arises from two formal one-elect ron reduction processes mediated by chlorine atom transfer. Oxygen ato m transfer occurs when the Ti(II) porphyrins are treated with several different sulfoxides or epoxides, resulting in two-electron redox prod ucts, (TTP)Ti=O, the sulfide or alkene, and EtC=CEt or THF. The electr onic properties of the substituents on the sulfoxides or epoxides corr elate with the yield and rate of the deoxygenation reactions.