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)]

Abstract

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.