Electron spin resonance studies of irradiated succinamic acid. I. Triclinic single crystals

Abstract
The products formed by x‐irradiation of single crystals of triclinic succinamic acid have been studied by electron spin resonance in the temperature range from 77° to 300°K. The primary product observed at 77°K is the oxidation radical, CONH2CH2ĊH2, (I), formed by decarboxylation. The two α‐hydrogens in I are exchanging rapidly and are equivalent at all orientations. Radical I decays by either an intermolecular or an intramolecular process to give two other products, CONH2CH2ĊHCOOH (II) or CONH2ĊHCH3 (III), respectively. Both II and III are stable at room temperature, however, III predominates in crystals irradiated at 300°K, whereas II predominates in crystals irradiated at 77°K and warmed to 300°K.