<i>N</i>,<i>N</i>-Linked biazoles. III. MNDO calculations on the conformation of <i>N</i>,<i>N</i>-linked biazoles and their quaternary salts

Abstract

A theoretical study of fourteen N,N-linked biazoles has been carried out using the MNDO method with full optimization of the geometries. The variation of energy as a function of the conformation around the central N—N bond shows in all cases the higher stability of the orthogonal or near-orthogonal form. The contribution of the three main types of "ortho" interactions [Formula: see text] and the effect of quaternization have been evaluated. Of the electronic properties calculated, one must emphasize the excellent agreement of dipole moments with experimental values.