Reactions of metal carbonyl derivatives. Part XVIII. Synthesis and redox properties of some binuclear derivatives of iron bridged by both carbonyl and alkylthio-groups

Abstract

The metal-containing sulphide RSMR′[R = Et or Bu^t, MR′= Fe(CO)₂(cp)] reacts with [Fe(cp)(CO)₂(OCMe₂)]⁺ to afford [{Fe(cp)(CO)₂}₂(SR)]⁺, in which the two iron atoms are linked through the alkylthio-group (cp =η-cyclopentadienyl). U.v. irradiation of [{Fe(cp)(CO)₂}₂(SR)][SbF₆] in tetrahydrofuran effects the loss of a carbonyl group and rearrangement of the resulting species to [Fe₂(cp)₂(CO)₃SR][SbF₆] containing both a bridging carbonyl and a bridging alkylthio-ligand. Similar treatment of [{Fe(cp)(CO)₂}₂(SEt)][BPh₄] results in extraction of a phenyl group from the tetraphenylborate anion and formation of [Fe(cp)(CO)₂Ph]. The cation [Fe₂(cp)₂(CO)₃SEt]⁺ is readily reduced by sodium amalgam to [Fe₂(cp)₂(CO)₃SEt] and [Fe₂(cp)₂(CO)₃SEt]^–.