The reactions of CH(3)CH(2)NH and (CH(3)CH(2))(2)N radicals with NO have been studied using quantum chemistry methods. The results show that formation of the nitrosamines CH(3)CH(2)NHNO and (CH(3)CH(2))(2)NNO is similar and that both isolated molecules are thermally stable. The nitrosamine formation reaction is highly exothermic, and the hot CH(3)CH(2)NHNO may undergo isomerization and subsequent reaction with O(2) to form the corresponding imine, CH(3)CH═NH. Time-dependent density functional theory (TDDFT) calculations show little difference of the vertical excitation energy between the π* ← n transitions in CH(3)CH(2)NHNO and (CH(3)CH(2))(2)NNO, and both will readily photolyze under sunlight conditions.