Facile Transfer Hydrogenation of Azo Compounds to Hydrazo Compounds and Anilines by Using Raney Nickel and Hydrazinium Monoformate

Visible-Light-Promoted Diboron-Mediated Transfer Hydrogenation of Azobenzenes to Hydrazobenzenes

“…Therein, the over-reduction of the azobenzenes to anilines may occur. In addition, toxic hydrazines were used to reduce azobenzenes in the presence of catalytic or stoichiometric amounts of noble transition metals . Recently, some well-designed main-group-elements such as B-, P-, and Bi-based catalysts have been successfully developed for the transfer hydrogenation of azobenzenes with ammonia-borane (NH 3 ·BH 3 ) (Scheme a).…”

Bioreductive molecular probe: fluorescence signalling upon reduction of an azo group

“…The intramolecular heterodimer probe (4) was reduced non-enzymatically by the catalyst RANEY s nickel 14 or sodium dithionite. 15 The diazo bond was rapidly converted to the fluorescent amine derivative (5), presumably through the intermediate formation of the hydrazine derivative.…”

Azobenzenes and catalysis

“…126,[135][136][137] Moreover, rhodium and nickel catalysis was reported in a few papers, including 1,2-addition and azobenzene cleavage into aniline. [157][158][159][160][161][162][163][164][165] Finally, azobenzene was also used as a core for the reaction promoter, especially in photochromic micellar catalysis in water. In this topic, all the works were reported by our group and concerned Tsuji-Trost catalysis or amidation.…”

“…161,162 Diphenylhydrazine can also be obtained depending on the temperature set to the reaction. 163 Instead of Raney nickel, silica gel supported nickel 164 or nickelcontaining mesoporous silicate molecular sieve catalyst can be used. 165 Furthermore, the NiMCM-41 catalyst tested was also found to be reusable, providing good to very good yields of the reaction.…”