Molecular polarisability. Quinoxaline and some of its derivatives

Abstract

The anisotropies of polarisability of pyridine, quinoxaline, and phenazine are compared with those for benzene, naphthalene, and anthracene. Replacement of CH– by N– appears to reduce all principal molecular axes in each case, but no stereospecificity of this diminution can be discerned among the three structural pairs considered. For 2,3-diphenylquinoxaline present measurements indicate a conformation in which the two phenyl rings are rotated in the same sense by ca. 39° out of the heterocyclic plane.