The length, strength and polarity of metal–carbon bonds: dialkylzinc compounds studied by density functional theory calculations, gas electron diffraction and photoelectron spectroscopy

Abstract

The molecular structures and thermodynamic functions of seven dialkyl zinc compounds, R2Zn, R = Me, Et, i-Pr, t-Bu, n-Pr, neopentyl and the silaneopentyl Me3SiCH2, of the parent hydrocarbons RH and of the radicals R have been determined by density functional theory calculations at the B3LYP/SDD level. The molecular structures of the i-Pr, t-Bu, neo-Pe and Me3SiCH2 derivatives have been determined by gas electron diffraction. Me2Zn, Et2Zn, t-Bu2Zn and neo-Pe2Zn have been studied by photoelectron spectroscopy and the ionisation energies calculated. Both experimental and calculated Zn-C bond distances were found to increase in the order Me2Zn ≈ (Me3SiCH2)2Zn < Et2Zn ≈ n-Pr2Zn ≈ neo-Pe2Zn < i-Pr2Zn < t-Bu2Zn.