Five-co-ordinate nitrosyl thiolato-complexes of molybdenum and tungsten. the preparation and X-ray crystal structures of [nHEt₃][Mo(SPh)₄(NO)],[PPh₄][WCl(SPh) ₃(NO)], and [mo(SC₆H₂Prⁱ₃-2,4,6) ₃(NH₃)(NO)]

Reaction of either [MCl₃(PPh₃)₂(NO)] (M = Mo or W) or '{Mo(NH₂O)(H₂O)_x(NO)}_n' with ^-SR (R = Ph, C₆H₄Me-4, C₆H₄Cl-4, C₆H₂Me₃-2,4,6, or Bu^t) in methanol gives the anionic five co-ordinate complexes [M(SR)₄(NO)]^- (M = Mo; R = Ph, C₆H₄Me-4, C₆H₄Cl-4, or C₆H₂Me₃-2,4,6), [MCl(SR)₃(NO)]^- (M = Mo, R = Bu^t; M = W, R = Ph). Crystal data: for [NHEt₃][Mo(SPh)_4-(NO)], space group P2₁/n with a = 10.996(2), b = 16.127(4), c = 18.845(4) Å, α = 90.00, β = 105.94(1), γ = 90.00°, and Z = 4; 2 786 reflections used in structure solution, giving R = 0.0516; for [PPh₄][WCl(SPh)₃(NO)], space group P2₁/c, a = 10.809(1), b = 19.677(3),c = 19.250(3) Å, α = 90.00, β = 105.85(1), γ = 90.00°, and Z = 4; 1 895 reflections giving R = 0.0375. Both anions have overall trigonal-bipyramidal geometries with apical NO groups. The reaction of the polymeric species '{Mo(NH₂O)(H₂O)_x(NO)}_n' with the sterically hindered thiol 2,4,6-tri-isopropylthiophenol in refluxing methanol affords the ammine complex [Mo(SC₆H₂Prⁱ₃-2,4,6) ₃(NH₃)(NO)]. Crystal data: space group P2₁/n with a = 10.477(3), b = 26.359(5), c = 20.1 24(4) Å, β = 87.21(1)°, and Z = 4; 1 040 reflections giving R = 0.078. The complex againhas trigonal-bipyramidal geometry with apical NO and NH₃ groups. The co-ordinated ammonia ligand arises from reduction of the co-ordinated hydroylamido-group.