In search of α-eliminations of carbon induced by sixteen electron iron: photolysis and thermolysis of derivatives of phenyl substituted cyclobutanes and cyclopropanes

Article abstract of DOI:10.1016/0022-328X(89)88078-7

Photolysis of dicarbonyl(ε⁵-cyclopentadienyl)(1-phenylcyclobutane-1-carbonyl)iron is proposed to give the hydride complex Ph(cyclobutenyl)Fe(Cp)(CO)H which dissociates to 1-phenylcyclobutene and FpH (Fp = ε⁵-cyclopentadienyldicarbonyliron).The FpH complex can oxidatively add to the sixteen electron acyl or ? complexes (Ph(cyclobutyl)-C(O)FeCp(CO) and Ph(cyclobutyl)FeCp(CO) respectively) to produce phenylcyclobutane and 1-phenylcyclobutane carboxaldehyde.Photolysis of dicarbonyl(ε⁵-cyclopentadienyl)(1-phenylcyclopropyl-1-carbonyl)iron gives a ? complex with no further reaction.Substitution of CO with PPh3 and thermolysis producrally substituted ?-allyl complex.In neither the cyclobutyl nor the cyclopropyl case did the reactions give isolable carbene complexes; apparently the phenyl substituent does not provide adequate stabilization of the carbene complex to allow its detection or isolation.