Mononuclear bis(dithiolene) Mo(iv) and W(iv) complexes with P,P; S,S; O,S and O,O donor ligands: a comparative reactivity study

Abstract

A new general synthetic strategy for a series of mononuclear bis(maleonitriledithiolato)Mo^IV and W^IV complexes with S,S; S,O and O,O donor ligands is described. The strategy includes the synthesis of two compounds, [M(mnt)₂(dppe)] (M = Mo, 1a; W, 1b; dppe, 1,2-bis diphenylphosphinoethane; mnt, maleonitrile dithiolate), which were then utilized for the synthesis of the complexes [M(mnt)₂(o-O,S-C₆H₄)](X)₂ (M = Mo, X = ‘PNP’, 2a; M = W, X = Ph₄P, 2b), [M(mnt)₂(o-O,O-C₆H₄)](Ph₄P)₂ (M = Mo, 3a; M = W, 3b) and [M (mnt)₂(bdt)](PNP)₂ (M = Mo, 4a; M = W, 4b). A detailed comparative description of the molecular structures, solution stability and redox reactions of these complexes is presented.