Nickel(II) complexes of heterodichalcogenido and monochalcogenido imidodiphosphinate ligands: AACVD synthesis of nickel ditelluride

The reaction of two equivalents of (TMEDA)Li[(EPiPr 2)(TePiPr2)N] (E = S, Se) with NiBr 2(DME) in THF at 23 °C yields homoleptic complexes of heterodichalcogenido PNP ligands Ni[(EPiPr2)(TeP iPr2)N]2 (2, E = S; 3, E = Se). Similarly, the complexes Ni[(PiPr2)(EPiPr2)N] 2 (4, E = Se; 5, E =Te) are obtained by in situ deprotonation of the neutral monochalcogenides EPiPr2NP(H)iPr 2 (E = Se, Te) with nBuLi in THF at -78 °C followed by addition of NiBr2(DME). The complexes 2-5 have been characterised by multinuclear (1H, 31P, 77Se and 125Te) NMR spectroscopy in solution and by X-ray crystallography in the solid state, the results of which show that they all exist as the square planar, trans isomers. Aerosol-assisted chemical vapour deposition (AACVD) of Ni[(SePiPr2)(TePiPr2)N]2 yields crystalline Ni0.51Te films at 450-500 °C, which were analysed by X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS). © 2008 The Royal Society of Chemistry.