Synthetic route to vanadium(III) dichalcogenidophosphinate complexes, V(S${}_2$PPh${}_2$)${}_3$ and V(Se${}_2$PPh${}_2$)${}_3$. A spectroscopic and structural comparative study with analogous complexes of Chromium(III), Cr(E${}_2$PPh${}_2$)${}_3$ (E=S, Se)

Addition of the potassium dichalcogenidodiphenylphosphinate salts, KE${}_2$PPh${}_2$ (E=S, Se), to either the THF solvate of vanadium(III) chloride or unsolvated chromium(III) chloride results in rapid ligand substitution and the formation of a series of closely-related trivalent, neutral mononuclear complexes, M(E${}_2$PPh${}_2$)${}_3$ (M=V, Cr; E=S, Se), isolated in modest to good yield. The metal dichalcogenidophosphinate complexes reported herein were characterized by IR, UV-vis, and ${}^1$H NMR spectroscopies, and their solid-state molecular structures were determined by single-crystal X-ray crystallography. Importantly, the comparative analysis includes the structural and spectroscopic studies of two rare V(III) dithio- and diseleno-phosphinate VE${}_6$ cores, as well as, two previously known CrE${}_6$ analogues. In the solid-state the title complexes exhibit trigonal distortion from octahedral with torsion angles ranging from 43(2) to 50.3(6)° and structural parameters consistent with ligation of progressively 'softer' chalcogen-donors. (© 2020 Wiley‐VCH GmbH)