The synthesis and single-crystal X-ray structures of palladium(II) and platinum(II) complexes of the difluorovinyl and 1-chloro-2-fluorovinyl-substituted phosphines, PPh2(Z-CFCFH) and PPh2(E-CClCFH)

The coordination chemistry of the fluorovinyl substituted phosphines PPh2(Z-CFCFH) and PPh2(E-CClCFH) with K2MX4 (M = Pd, Pt; X = Cl, Br, and I) salts has been investigated resulting in the first reported palladium(II) and platinum(II) complexes of phosphines containing partially fluorinated vinyl groups. The complexes have been characterised by a combination of multinuclear [1H, 13C{1H}, 19F, 31P{1H}] NMR spectroscopy, and IR/Raman spectroscopy. The single-crystal X-ray structures of trans-[PdX2{PPh2(CFCFH)}2], X = Cl (1), Br (2), I (3), trans-[PdCl2{PPh2(CClCFH)}2] (4), cis-[PtX2{PPh2(CFCFH)}2], X = Cl (5), Br (6), trans-[PtI2{PPh2(CFCFH)}2] (7), and both cis- and trans-[PtCl2{PPh2(CClCFH)}2] (8), have been determined. Results obtained from spectroscopic and crystallographic data suggest that replacement of a β-fluorine by hydrogen, whilst reducing the steric demand of the ligand, has little effect on the electronic character of the ligand. The presence of a proton in the vinyl group results in short proton–halide secondary interactions in the solid state (d(H⋯X) = 2.72(3) for 1, and 2.92(5) Å for 2) forming an infinite chain ribbon motif.