cis- and trans-Influences in platinum(II) complexes. X-Ray crystal-structure analysis of cis-dichloro(triethylphosphine)(trifluorophosphine)platinum(II)

Abstract

Crystals of cis-[PtCl₂(PEt₃)(PF₃)] are monoclinic, P2₁/n, with a= 11.813(6), b= 17.27(6), c= 6.67(3)Å, β= 91.29(2)°, and Z= 4. Least-squares refinement based on 1 957 reflection intensities has converged at R= 0.038. The co-ordination at platinum is approximately square planar with angle P–Pt–P 101.3(1)° and bond lengths Pt–PEt₃ 2.272(3), Pt–PF₃ 2.141(3), Pt–Cl 2.357(3)(trans to PEt₃), and 2.305(3)Å(trans to PF₃). The shorter Pt–P bond to PF₃ is at least partly due to the effect of electronegative substituents on the phosphorus lone-pair orbital, and the difference in the Pt–Cl lengths can be accounted for by changes in the σ orbitals of the complex. Correlations are noted between the lengths of mutually trans Pt–PX₃ and Pt–Cl bonds and between the lengths of mutually trans Pt–PEt₃ and Pt–Cl bonds in complexes cis-[PtCl₂L(PEt₃)].