CONFORMATIONAL ANALYSIS OF SUBSTITUTED 1,3,2–OXAZABORINANES

Abstract

The empirical (MM2) and semiempirical (AM1, MNDO) methods were used to calculate the energy of unsubstituted and 2-, 3-, 5-, 3,5-, and 2,3,5-substituted 1,3,2-oxazaborinanes with complete geometrical optimization. The major minimum on the potential energy surface corresponds to the sofa conformation. The number of other local minima relates to the half-chair and 1,4-, 3,6-, and 2,5-twist conformations. The experimental ΔG⁰ value for 5-methyl group on the C₍₅₎ carbon atom was determined by comparison of calculated and experimental spin-spin coupling constants.

Author: V. V. Kuznetsov.

English Translation in Chemistry of Heterocyclic Compounds, 1999, 35 (8), pp 928-934

http://link.springer.com/article/10.1007/BF02252160