Conformational analysis of some β-halohydrins via G3 calculations

Abstract EN

The conformational analysis of fifteen β-halohydrins, XCR1R2CR3R4OH, (X = F, Cl and Br) had been studied by ab initio G3 method.

The enthalpies of formation values were calculated for nine conformers of each β-halohydrin.

The (g-, g+) and (g+, g-) conformers were found to be the most stable due to intramolecular H-bond formation.

These H-bonds are weaker than intermolecular H-bonds formed between alkyl halides and alcohols.

This trend is more obvious in flouro-species.

The rotation of C- X bond of (g-, g+) conformers by 360 ° gives three transition states, this rotation was found to require 6-7 kcal / mol.