The crystal structure of two cobalt(I) complexes containing the polyphosphine ligands PhP{(CH₂)_nPPh₂}2 (n = 2, 3)

Abstract

X-ray diffraction analysis of the two complexes [CoPhP{(CH₂)₃PPh₂}₂P(OMe)₃CO] BF₄,thf and [CoPhP{(CH₂)₂PPh₂}₂{P(OMe)₃}₂] BF₄ are reported. Crystals of the first complex are triclinic, space group Pī with a 14.310(1), b 11.080(2), c 16.099(3) Ǻ, α 68.30(2), β 90.78(2), γ 75.04(1)°. The structure analysis has been based on 2964 independent reflection intensities (Cu Kα automatic diffractometry) to give R 0.11. The second complex is monoclinic, space group P2₁/c, with a 13.18(4), b 11.49(3), c 29.66(6) Ǻ, β 101.59(2)°. Refinement by least squares has converged to R 0.093 for the 2256 independent reflection intensities, observed by Mo Kα automatic diffractometry. The preferred stereochemistries of the five-coordinate cobalt complexes are discussed in relation to the bite angle of the chelating phosphine.