THE FIRST SUCCESSFUL DIRECT AZOCOUPLING OF NITROAROMATIC ANION-RADICAL

Article abstract of DOI:10.1016/S0040-4020(01)86026-9

o-Dinitrobenzene dianion reacts with p-N,N-dimethylaminobenzenediazonium cation, forming 2-nitro-4'-N,N-dimethylaminoazobenzene. o-Dinitrobenzene anion-radical, interacting with benzenediazonium cations that contain N,N'-dimethylamino or nitro group in para-position, yields 3-nitro-4-hydroxy-4'-N,N-dimethylaminoazobenzene and 3,4'-dinitro-4-hydroxyazobenzene, respectively.The above compounds are formed in media promoting the stability of ion pairs between o-dinitrobenzene dianions or anions-radicals and potassium cations.With the dissociation of ion pairs, only the electron-transfer reaction products are observed.