Reaction of bulky monosubstituted phosphorus(III) halides with disodium tetracarbonylferrate. Steric and electronic factors in the synthesis of Fe(CO)4 complexes of diphosphene and phosphinidene ligands

Abstract

Reaction of Na/sub 2/Fe(CO)/sub 4/ with a bulky monosubstituted phosphorus(III) halide RPCl/sub 2/ where R = Mes (2,4,6-Me/sub 3/C/sub 6/H/sub 2/), CH/sub 2/SiMe/sub 3/, CH(SiMe/sub 3/)/sub 2/, N(SiMe/sub 3/)/sub 2/, -OC/sub 6/H/sub 2/-2,6-t-Bu/sub 2/-4-Me, or -OC/sub 6/H/sub 2/-2,4,6-t-Bu/sub 3/ yields products in which the phosphorus center behaves as either a diphosphene or a bridging phosphinidene group. The type of product depends on the substituent used. The synthesis of two precursor ligands, 2,4,6,-t-Bu/sub 3/C/sub 6/H/sub 2/OPCl/sub 2/ and 4-Me-2,6-t-Bu/sub 2/C/sub 6/H/sub 2/OPCl/sub 2/, and eight iron carbonyl complexes involving various diphosphene and phosphinidene ligand are described and discussed in the context of the corresponding chromium carbonyl complexes.