Synthesis, Characterization and X-Ray Crystal Structure of {H₂B(Me₂C₃N₂H)₂}Mo^IVO(S₂PPr^I₂)

Abstract

Reaction of MoO (S₂PPrⁱ₂)₂ and K{H₂B(Me₂C₃N₂H)₂} in refluxing toluene produces green, diamagnetic, air-stable {H₂B(Me₂C₃N₂H)₂}Mo^IVO(S₂Pprⁱ₂)(1), which has been characterized by analytical, mass spectrometric, infrared and n.m.r. spectroscopic, and X-ray crystallographic techniques. Crystals of (1) are triclinic and belong to space group Pī , with a 10.289(1), b 13.601(2), c 8.737(1) Ǻ, α 94.31(1), β 107.71(1), γ 79.56(1)°, V 1145.2 Ǻ³ and Z 2. The structure was solved by Patterson and Fourier methods and refined by using 3631 reflections to a final R value of 0.024 ( Rw 0.041). The five-coordinate square pyramidal complex is composed of apical terminal oxo [Mo-O(1) 1.658(2)Ǻ] and bidentate H₂B(Me₂C₃N₂H)₂^- and S₂PPrⁱ₂^- ligands coordinated to molybdenum. Ferrocenium oxidation of (1) produces the mononuclear molybdenum(V) complex [{H₂B(Me₂C₃N₂H)₂}Mo^VO(S₂Pprⁱ₂)]⁺ ( e.p.r .: g 1.964, a(^95,97Mo) 41.7×10^-4cm^-1, a(³¹P) 30.1×10^-4 cm^-1).