An Azocine Anion Radical and Heats of Formation of Azocine Dianions

Article abstract of DOI:10.1021/ja00357a019

3,8-Dimethyl-2-methoxyazocine was reduced to its anion radical in hexamethylphosphoramide (HMPA).The ESR spectrum of the DMMA anion radical resembles one recorded from a monosubstituted cyclooctatetraene anion radical where the substituent is an electron-withdrawing group.Calorimetric techniques were utilized to study the thermodynamic stability of the DMMA dianion.This dianion is more stable relative to the metal and neutral molecule than is either the cycloocatetraene (COT) or tert-butoxycycloocatetraene dianion.The unexpected stability of DMMA^2- is attributed to strong interactions between the cation (Na⁺) with the oxygen and/or nitrogen atoms.This same interaction shifts the disproportionation of DMMA^-. to the right in solvents where ion association is prevalent.