METAL ATOM SYNTHESIS OF IRON DIENE PHOSPHITE COMPLEXES

Complexes of the type Fe(η4-diene)L3(where L are phosphorus ligands) have been prepared for a variety of simple cyclic and acyclic dienes by metal atom evaporation techniques. In addition, complexes of the type Fe(η4-diene)2L have been prepared for acyclic dienes. The Fe(diene)L3complexes show temperature-dependent31P{1H} NMR behavior; analysis of these spectra yields mechanistic information concerning the nature of the rearrangement process. Iron atom evaporation syntheses with cyclohexadiene and trimethyl phosphite give the additional complexes Fe(η4-1,3-C6H8)(η2-1,4-C6H8)L2, Fe(η6-C6H6)L2, Fe(η6-C6H6)Fe(η4-1,3-C6H8), and FeP2(η5-cyclohexadienyl)(hydride). Species related to the latter compound are cited as intermediates in proposed mechanisms for several observed hydrogen-transfer reactions including the conversion of cyclohexadiene to benzene and cyclohexene. © 1979, American Chemical Society. All rights reserved.