Solution chemistry and reactivity of tris(N,N-dialkyldithiocarbamato)oxomolybdenum(VI) cationic complexes

Abstract

The preparation of the orange diamagnetic compounds [MoO(S₂CNR₂)₃]X (R = Me or Et, X = BF₄^–, PF₆^–, or ClO₄^–; R = Prⁱ, X = BF₄^–) from the reaction of cis-[MoO₂(S₂CNR₂)₂] complexes and HX in acetone is described. Details of the ¹H and ¹³C-{¹H} n.m.r., i.r., and electronic spectra of the complexes are presented. The monomeric complex cations possess a rigid pentagonal-bipyramidal geometry in solution at room temperature. The complex [MoO(S₂CNEt₂)₃]⁺ catalytically converts PPh₃ into OPPh₃ in air, gives [Mo(NPh)(S₂CNEt₂)₃]}⁺ with PhNCO, undergoes replacement of one S₂CNEt₂^– ligand with Cl^– and S₂^2–, and yields [MoO(S₂CNEt₂)₂] upon reduction.