Molybdenum, rhenium, and tungsten complexes with bi- and tri-dentate phosphinothiolato-ligands; structures of [Mo{PhP(CH2CH2S)2}2] and [Mo(NNMe2){PhP(CH2CH2S)2}2]

Abstract

[ReOCl₃(PPh₃)₂] reacts with two equivalents of Ph₂PCH₂CH₂SH in tetrahydrofuran to give [ReOCl(Ph₂PCH₂CH₂S)₂]. An excess of tridentate PhP(CH₂CH₂SH)₂ reacts with [ReOCl₃(PPh₃)₂] to yield [Re{PhP(CH₂CH₂S)₂}{PhP(CH₂CH₂S)(CH₂CH₂SH)}] containing a pendant unto-ordinated SH group. This complex reacts reversibly with CO to form [Re{PhP(CH₂CH₂S}{PhP(CH₂-CH₂S)(CH₂CH₂SH)}(CO)][ν(CO) at 1 980 Cm^–1]. The M^IV complexes [MCl₄L₂][M = MO or W, L = PPh₃ or MeCN) react with PhP(CH₂CH₂SH)₂ in MeOH to give [M(PhP(CH₂CH₂S)2)2]. An X-ray crystal-structure determination for the complex with M = MO showed a distorted octahedral structure with an average MO–S distance of 2.44 Å. The complex crystallises in the triclinic space group p, with a= 10.601(7), b= 10.867(4), c= 12.347(1)Å, α= 66.98(3), β= 85.60(4), γ= 63.70(4)°, and Z= 2. 1 337 Unique reflections with I₀ 3σ(I₀) used in the solution converged at R= 0.0979. The hydrazido(2–) complexes [MCl(NNMe₂)₂(PPh₂)₂]Cl react with PhP(CH₂CH₂SH)₂ in MeOH to give [M(NNMe₂){PhP(CH₂CH₂S)₂}₂](M = MO or W). An X-ray crystal-structure determination of the complex with M = MO revealed a distorted pentagonal-bipyramidal structure with a linear apical NNMe₂ ligand. The complex crystallises in the monoclinic space group P2₁/n, with a= 11.349(2), b= 12.403(3), c= 19.302(4)Å, β= 104.28(2)°, and Z= 4. 2 796 Unique reflections with I₀ > 3σ(I₀) used in the solution converged at R= 0.605.