SYNTHESIS AND SOLUTION MULTINUCLEAR NUCLEAR-MAGNETIC-RESONANCE STUDIES OF HOMOLEPTIC COPPER(I) COMPLEXES OF GROUP-15 DONOR LIGANDS

The homoleptic complexes [CuL4]Y (L = PMe3, PMe2Ph, PMePh2, PPh3, PPh2H, PPhH2, AsMe3, AsMe2Ph, AsMePh2, AsPh3, SbMe3, SbEt3 or SbPh3; Y = PF6 or BF4) and [Cu(L-L)2]Y [L-L = Me2P(CH2)2PMe2, o-C6H4(PMe2)2, Ph2P(CH2)nPPh2 (n = 1-4), cis-Ph2PCH=CHPPh2, o-C6H4(PPh2)2, o-C6H4(AsMe2)2, cis-Ph2AsCH=CHAsPh2, o-C6H4(SbMe2)2, MeSb(CH2)3SbMe2 or Ph2Sb(CH2)3SbPh2] have been prepared from [Cu(MeCN)4]Y and L or L-L. The Cu-63 and, where appropriate, P-31{H-1} NMR spectra, have been recorded from CH2Cl2 solutions of the complexes over the temperature range 300-175 K, including the first reported Cu-63 resonances from arsenic and antimony donor ligand compounds. The effects of ligand size and geometry upon the Cu-63 NMR spectra are discussed and typical copper chemical-shift ranges for Group 15 donor ligand compounds established. The structure of [Cu(cis-Ph2AsCH=CHAsPh2)2]PF6 has been established by X-ray crystallography: orthorhombic, space group P2(1)2(1)2(1), a = 14.775(6), b = 16.991(5), c = 21.027(6) angstrom, Z = 4. The copper atom is in a distorted tetrahedral environment [Cu-As 2.348(3)-2.358(3) angstrom].