G. Dyer et J. Roscoe, DEVELOPMENT OF A SYNTHETIC ROUTE TO UNSYMMETRICAL TRIPHOSPHINE LIGANDS AND AN INVESTIGATION OF THEIR COORDINATION CHEMISTRY WITH NICKEL ANDPALLADIUM, Inorganic chemistry, 35(14), 1996, pp. 4098-4102
Chiral tridentate phosphines, R(2)P(CH2)(3)PPh(CH2)(2)PPh(2) where E =
C6H5, p-ClC6H4, and p-FC6H4, can be prepared from simple starting mat
erials, (R(3)P, I(CH2)(3)I, and Ph(2)P(CH2)(2)PPh(2)), in a few stages
involving phosphonium salts and phosphine oxides as intermediates. Cr
ystalline diamagnetic complexes of nickel(II) and palladium(II) have b
een isolated. In solution these show first-order 12 line P-31 NMR spec
tra consistent with three nonequivalent phosphorus nuclei coupled to o
ne another in a square planar geometry. A single X-ray crystallographi
c study of NiI2{P(CH2)(3)PPh(CH2)(2)PPh(2)} showed that this was squar
e pyramidal in the solid state with a weakly held apical iodo ligand.