Structural studies of steric effects in phosphine complexes. Part 4. Synthesis and crystal and molecular structure of trans-di-iodobis(tri-o-tolylphosphine)platinum(II)–dichloromethane (1/1)

Abstract

The title complex has been synthesized and crystallizes in a 1 : 1 ratio with dichloromethane in the monoclinic space group C2/c with a= 22.100(3), b= 9.961 (3), c= 21.516(3)A, β= 113.19(1)°, and Z= 4. The structure has been solved by Patterson and Fourier methods and refined by full-matrix least-squares techniques to a final R of 0.036 for 3 073 observed reflections measured by diffractometer. The dichloromethane is disordered over three equally populated sites around the crystallographic two-fold axis. The trans-[Ptl2{P(C6H4Me-o)3}2] molecule resides on a crystallographic centre of symmetry with Pt–I and Pt–P distances of 2.622(1) and 2.348(2)A respectively. The failure of this complex to undergo intramolecular metallation can be explained by the steric effects of the P(C6H4Me-o)3 ligand, which are described by cone-angle calculations (θ= 183°) and a ‘ligand profile’.