Five-co-ordinate complexes [MoH(SC6H2R3-2,4,6)3(PR′Ph2)](R = Me or Pri, R′= Me or Et) and their reactions with nitrogen donors. Crystal structures of [MoH(SC6H2Pri3-2,4,6)3(C5H5N)(PMe2Ph)], [MoH(NC5H4S-2)2(SC6H2Pri3-2,4,6)(PEtPh2)] and [PPh4][MoO(SC6H2Pri3-2,4,6)4]

Abstract

The complexes [MoH(SC₆H₂R₃-2,4,6)₃(PR′Ph₂)]1(R = Me or Prⁱ, R′= Me or Et) have been prepared by reaction of HSC₆H₂R₃-2,4,6 with [MoH₄(PR′Ph₂)₄] or trans-[Mo(N₂)₂(PR′Ph₂)₄]. Compound 1(R = Prⁱ, R′= Me) reacted with N-donor ligands L (C₅H₅N, 3-MeC₅H₄N, 3,5-Me₂C₅H₃N or C₃H₃NS) to give the adducts 2, [MoH(SC₆H₂Prⁱ₃-2,4,6)₃L(PMePh₂)]. The crystal structure of the analogue [MoH(SC₆H₂Prⁱ₃-2,4,6)₃(C₅H₅N)(PMe₂Ph)] showed the compound to have a trigonal girdle of thiolate ligands with the pyridine and PMe₂Ph ligands in essentially apical positions. Reaction of 1(R = Prⁱ, R′= Et) with NC₅H₄SH-2 gave the seven-co-ordinate complex [MoH(SC₆H₂Prⁱ₃-2,4,6)(NC₅H₄S-2)₂-(PEtPh₂)], shown by X-ray crystallography to have an essentially pentagonal-pyramidal geometry with the hydride located in the equatorial plane. Spectroscopic data for the compounds are discussed in terms of their structures. Complex 1(R = Prⁱ, R′= Et) exchanges hydride for deuteride on treatment with deuterium gas in benzene at 20 °C. Treatment of 1(R = Prⁱ, R′= Me) in MeOH with LiBEt₃H, followed by [PPh₄]Cl, gave [PPh₄][MoO(SC₆H₂Prⁱ₃-2,4,6)₄], shown by X-ray crystallography to have an anion with square-pyramidal geometry and an apical oxide-ligand.