Steric effects induced by ferrocenyl in tertiary organophosphines: crystal structure of trans-chloromethylbis(ferrocenyldiphenylphosphine)palladium(II) benzene disolvate

Abstract

The structure determination of the title compound, trans-[PdMeCl(PPh 2Fc) 2]·2C 6H 6, (PPh 2Fc=C 22H 19FeP) shows the Pd(II) moiety to have a square planar geometry with the bulky phosphine ligands in a trans orientation. The compound crystallises in the triclinic space group P1̄ with 1 mole per unit cell accompanied by two benzene solvent molecules. A 50% statistical disorder was observed in the methyl and chloride positions. Bond distances and angles of the coordination polyhedron are PdP=2.3328(10) Å, PdCl=2.378(3) Å, PdC(10)=2.108(10) Å, PPdCl=92.70(9)° and PPdC(10)=86.8(4)°. The structure is compared with the isomorphous trans-[Pt(Cl) 2(PPh 2Fc) 2]·2C 6H 6 and other relevant structures of Pt(II) and Pd(II) described in the literature. The steric demand of the PPh 2Fc ligand was estimated from all known structures to be approximately 155° using the Tolman model.