Bi- and ter-molecular electron donor–acceptor complex formation between hexamethylbenzene and 1,3,5-trinitrobenzene, and also between NNN′N′-tetramethyl-p-phenylenediamine and 1,3,5-trinitrobenzene in solution

Abstract

The dependence of the line position in the ¹H n.m.r. spectra of dilute solutions of the electron acceptor (A) 1, 3, 5-trinitrobenzene on the concentration of excess of the electron donor (D) hexamethylbenzene in various paraffinic solvents has been interpreted in terms of equilibria involving the complex species DA and D₂A. The equilibrium quotients have been evaluated on several concentration scales.

The same interpretation provides a satisfactory explanation for similar observations involving the interaction of NNN′N′-tetramethyl-p-phenylenediamine with 1, 3, 5-trinitrobenzene. The results are in accord with those obtained from optical measurements.

Activity coefficient effects in themselves appear to be too small to provide an alternative explanation of the observed behaviour.