81572-30-7Relevant academic research and scientific papers
The reaction of triorganophosphorus diiodides, R3PI2, with zinc metal powder; Dependency of product on R; The X-ray crystal structures of dimeric {ZnI2[P(NMe2)3]}2 and monomeric ZnI2(PPh2Me)2
Godfrey, Stephen M.,McAuliffe, Charles A.,Pritchard, Robin G.,Sheffield, Joanne M.
, p. 213 - 219 (2008/10/08)
Seventeen zinc(II) tertiary phosphine complexes have been synthesised directly from elemental zinc by reaction with the reagents R3PI2. The complexes have been characterised by elemental analysis and 31P{H} NMR spectroscopy. The present work represents the first comprehensive study of a wide variety of zinc(II) tertiary phosphine complexes containing different parent tertiary phosphines and the majority of the complexes are reported for the first time. In most cases, reaction of R3PI2 with zinc metal powder in diethyl ether in a 1:1 stoichiometric ratio, produces the dimeric complexes [ZnI2(PR3)]2, analogous to the previously reported [ZnI2(PEt3)]2. In contrast, reaction of R3PI2 (R=Ph3, Ph2Et, Ph2Me) with zinc metal powder produces the monomeric bis complexes ZnI2(PR3)2 and an equimolar quantity of zinc(II) iodide, the latter product being identified by X-ray powder diffraction. The X-ray crystal structures of dimeric {ZnI2[P(NMe2)3]}2 and monomeric ZnI2(PPh2Me)2 are also described. The formation of the bis complexes ZnI2(PR3)2 (R3=Ph3, Ph2Me, Ph2Et) is surprising and cannot be due to steric factors since complexes containing less bulky tertiary phosphines are shown to be dimeric and the adoption of a monomeric zinc(II) centre increases steric crowding at the metal atom. The existence of the bis complexes is therefore reasoned to be due to favourable Π-Π interactions on the ligands and crystal packing forces.
Reinvestigation of tricyclohexylphosphine complexes of zinc(II) and cadmium(II) halides. Preparation, characterization, and phosphorus-31 nuclear magnetic resonance and vibrational spectroscopic studies
Goel, Ram G.,Henry, William P.,Jha, Narendra K.
, p. 2551 - 2555 (2008/10/08)
Zinc(II) halides form isolable 1:1 complexes with tricyclohexylphosphine. Previously reported 1:2 complexes, ZnX2[P(cy)3]2, are indicated to be ZnX2P(cy)3[OP(cy)3] by 31P{1H} NMR spectral measurements. Cadmium(II) halides form isolable 1:1 as well as 1:2 complexes with tricyclohexylphosphine. Molecular weight data show that the 1:1 complexes of both zinc(II) and cadmium(II) halides exist in solution as dimeric molecular species, M2X4[P(cy)3]2. The far-infrared and Raman spcectra for these complexes, in the solid state, are consistent with a dimeric structure of C2v skeletal symmetry. Vibrational spectra of the CdX2[P(cy)3]2 complexes, in the solid state, are consistent with a pseudotetrahedral structure of C2v skeletal symmetry. Phosphorus-31 NMR spectral measurements at 306 ± 2 K show that the 1:2 complexes, CdX2[P(cy)3]2, dissociate extensively in solution into the 1:1 complexes and P(cy)3; no such dissociation is evident at 213 K. Phosphorus-31 NMR spectra of the Zn2X4[P(cy)3]2 and Cd2X4[P(cy)3]2 complexes have also been examined at 306 ± 2 K and at 183 or 213 K.
