Stochastic Search for Isomers of the sec-Butyl Cation

Valerije Vrček; Olga Kronja; Martin Saunders

doi:10.1021/ct600308b

Stochastic Search for Isomers of the sec-Butyl Cation

J Chem Theory Comput. 2007 May;3(3):1223-30. doi: 10.1021/ct600308b.

Authors

Valerije Vrček¹, Olga Kronja¹, Martin Saunders¹

Affiliation

¹ Faculty of Pharmacy and Biochemistry, University of Zagreb, A. Kovačića 1, 10000 Zagreb, Croatia, and Department of Chemistry, Yale University, New Haven, Connecticut 06520.

PMID: 26627441
DOI: 10.1021/ct600308b

Abstract

A stochastic search procedure for locating energy minimum structures was applied to the sec-butyl cation. A previously unreported structure 3' with strong H-hyperconjugative stabilization of the carbocation center was found at several levels of theory (HF, B3LYP, and MP2). The theoretical equilibrium isotope effect (EIE) for the monodeutero isotopomer of 3' (Keq = 1.4; t = -130 °C) indicates that the new structure is likely to be largely responsible for the experimentally observed EIE.