Two homologous series of pnictogen(III) dications, stabilized by 2,6-bis(benzimidazole-2-yl)pyridine ligands have been prepared. Both series contain PnIII-X moieties (Pn = P, As, Sb, Bi; X = Cl or Ph) and have been fully characterized using spectroscopic methods including X-ray crystallography. The Lewis acidity of these compounds has also been probed by computational methods; the results suggest that the dictations are strong Lewis acids, with the PnCl2+ compounds being more acidic than the PnPh2+ compounds, and with Lewis acidity increasing from P to Bi, in both series. The PhP2+-containing compound was also found to be a versatile PIII transfer reagent, leading to new synthetic routes for various PhP-containing compounds. The redox chemistry of all compounds has also been probed using cyclic voltammetry and chemical reductions. In some cases the resulting PnI moieties could be trapped using diazabutadienes.
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