Coordination chemistry of a new P,Te-centred ligand: synthesis, NMR spectra and X-ray structures of M(TePPri2NPPri2)2 (M = Zn, Cd, Hg)

Abstract

The lithiation of the monotelluride TePPrⁱ₂NP(H)Prⁱ₂ (2) with BuⁿLi at −78 °C results in the formation of the reagent [LiTePPrⁱ₂NPPrⁱ₂] (5), which was characterized by ³¹P NMR spectroscopy but not isolated due to disproportionation upon solvent removal. Salt metathesis reactions of 5, generated in situ, with group 12 metal chlorides produce the complexes M(TePPrⁱ₂NPPrⁱ₂)₂ (6, M = Zn; 7, M = Cd; 8, M = Hg), which were characterized by single crystal X-ray diffraction, multinuclear NMR spectroscopy and thermal analyses. The X-ray structures reveal distorted tetrahedral structures with two P,Te-chelating anionic ligands [TePPrⁱ₂NPPrⁱ₂]⁻. The ³¹P NMR spectra exhibit second order behaviour that arises from an AA′XX′ spin system; the spectra were simulated to determine the ³¹P, ³¹P spin–spin coupling constants.