Carbon-Oxygen Hydrogen Bonding in Dehydrohalogenation Reactions: PM3 Calculations on Polyhalogenated Phenylethane Derivatives

Han Zuilhof; Gerrit Lodder; Heinz F. Koch

doi:10.1021/jo962154w

Carbon-Oxygen Hydrogen Bonding in Dehydrohalogenation Reactions: PM3 Calculations on Polyhalogenated Phenylethane Derivatives

J Org Chem. 1997 Oct 17;62(21):7457-7463. doi: 10.1021/jo962154w.

Authors

Han Zuilhof¹, Gerrit Lodder, Heinz F. Koch

Affiliation

¹ Laboratory of Organic Chemistry, Department of Biomolecular Sciences, Wageningen Agricultural University, Dreijenplein 8, 6703 HB Wageningen, The Netherlands, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands. and Department of Chemistry, Ithaca College, Ithaca, New York 14850.

PMID: 11671864
DOI: 10.1021/jo962154w

Abstract

The dehydrohalogenation reactions of PhCH(2)-CH(2)Cl and PhCHCl-CX(2)LG (X = H, F; LG = F, Cl) with methoxide have been studied using PM3 quantum chemical calculations in vacuo and within a dielectric medium. For PhCH(2)-CH(2)Cl and PhCHCl-CH(2)Cl the loss of HCl is predicted to occur via an E2 mechanism, while for the other three compounds loss of hydrogen halide occurs via a two-step mechanism, with a hydrogen-bonded carbanion as an intermediate. The mechanistic implications of these calculations are discussed in comparison with experimental data.