Oxidative-addition reactions of Mel or CH2I2 to [M2(µ-pz)(µ-SBut)(CO)2{P(OMe)3}2](M = Rh or Ir) complexes. X-Ray structure of [Ir2(µ-pz)(µ-SBut)(µ-CH2)I2(CO)2{P(OMe)3}2](pz = pyrazolate)

Abstract

The heterobridged binuclear complexes of general formula [M₂(µ-pz)(µ-SBu^t)(CO)₂{P(OMe)₃}₂](pz = pyrazolate; M = Rh, 1; or Ir, 2) react with methyl iodide to give [M₂(µ-pz)(µ-SBu^t)(Me)I(CO)₂{P(OMe)₃}₂](M = Rh, 3; or Ir, 4). Reaction of the diiridium complexes 2 or [Ir₂(µ-dmpz)(µ-SBu^t)(CO)₂{P(OMe)₃}₂](dmpz = 3,5-dimethylpyrazolate) with diiodomethane give [Ir₂(µ-pz)(µ-SBu^t)(µ-CH₂)I₂(CO)₂{P(OMe)₃}₂]5 or [Ir₂(µ-dmpz)(µ-SBu^t)(CH₂I)I(CO)₂{P(OMe)₃}₂] respectively. The crystal and molecular structure of 5 has been determined by X-ray diffraction methods. Crystals are monoclinic, space group P2₁/c, with a= 11.398(1), b= 16.571(2), c= 16.274(2)Å, β= 106.87(1)°, and Z= 4. The molecule is binuclear, with the two metal centres bridged by a pyrazolate anion, a SBu^t group and a methylene carbon atom.