Studies on sulfenamides. XI. Electron spin resonance spectra of radical cations electrochemically generated from N,N-disubstituted 2-nitrobenzenesulfenamides.
作者:HIROTERU SAYO、TAKASHI MICHIDA、HIROMI HATSUMURA
DOI:10.1248/cpb.34.558
日期:——
The paramagnetic species formed by in situ electrochemical oxidation of N-(2-nitrophenyl-thio)dibenzylamine (1) and three N-methyl-4'-substituted 2-nitrobenzenesulfenanilides (4'-CH3 (2), 4'-C(CH3)3 (3), 4'-COOC2H5 (4)) have been identified as the radical cations derived from the parent sulfenamides by one-electron transfer. On the other hand, the radicals generated from three 4'-unsubstituted N-alkyl-2-nitrobenzenesulfenanilides (N-CH3 (5), N-C2H5 (6), N-CH2C6H5 (7))have been identified as the radical cations of N, N-dialkyl-diphenoquinone-diimines formed by dimerization of the sulfenanilide radical cations and further oxidation of the dimers. From the voltammetric data, it is proposed that the dimerization takes place before the cleavage of the S-N bond in the sulfenanilide radical cations.
N-(2-硝基苯硫基)二苄胺 (1) 和三个 N-甲基-4'-取代的 2-硝基苯磺酰苯胺 (4'-CH3 (2), 4'-C( CH3)3 (3)、4'-COOC2H5 (4)) 已被确定为通过单电子转移衍生自母体次磺酰胺的自由基阳离子。另一方面,由三个 4'-未取代的 N-烷基-2-硝基苯磺酰苯胺 (N-CH3 (5)、N-C2H5 (6)、N-CH2C6H5 (7)) 生成的自由基已被确定为自由基阳离子通过亚磺酰苯胺自由基阳离子的二聚和二聚体的进一步氧化而形成的N,N-二烷基-二苯醌-二亚胺。根据伏安数据,推测二聚发生在亚磺酰苯胺自由基阳离子中的S-N键断裂之前。