Synthesis and solution multinuclear nuclear magnetic resonance studies of homoleptic copper(I) complexes of Group 15 donor ligands
Abstract
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-Ph2PCHCHPPh2, o-C6H4(PPh2)2, o-C6H4(AsMe2)2, cis-Ph2AsCH
CHAsPh2, o-C6H4(SbMe2)2, Me2Sb(CH2)3SbMe2 or Ph2Sb(CH2)3SbPh2] have been prepared from [Cu(MeCN)4]Y and L or L–L. The 63Cu and, where appropriate, 31P-{1H} NMR spectra, have been recorded from CH2Cl2 solutions of the complexes over the temperature range 300–175 K, including the first reported 63Cu resonances from arsenic and antimony donor ligand compounds. The effects of ligand size and geometry upon the 63Cu 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 P212121, a= 14.775(6), b= 16.991(5), c= 21.027(6)Å, Z= 4. The copper atom is in a distorted tetrahedral environment [Cu–As 2.348(3)–2.358(3)Å].