605-84-5Relevant academic research and scientific papers
An easy access to aromatic azo compounds under ultrasound/microwave irradiation
Cravotto, Giancarlo,Boffa, Luisa,Bia, Marco,Bonrath, Werner,Curini, Massimo,Heropoulos, Georgios A.
, p. 2605 - 2608 (2008/09/16)
Chemoselective reduction of nitroarenes to azo and azoxy compounds was easily achieved using zinc powder and ammonium chloride in DMF or DMF-water (95:5) under high intensity ultrasound (US) or microwave (MW) irradiation, separately or combined. When carried out under conventional heating the reaction required much higher temperatures and gave lower yields. The addition of a small amount of water caused a dramatic increase in the reactivity, permitting the reduction of hindered nitroarenes at the expense of selectivity. A novel reactor for combined US/MW irradiation was employed which demonstrated additional beneficial effects. Georg Thieme Verlag Stuttgart.
Reduction of Nitroarenes Using an Activated Catalyst Prepared by the Reduction of Nickel Nitrate with Excess Zinc in the Presence of Hydrazine Monohydrate
Yun, Tae Ho,Park, Moon Keu,Han, Byung Hee
, p. 2774 - 2788 (2007/10/02)
An activated catalyst prepared from a mixture of nickel nitrate hexahydrate with zinc in dry ethanol under reflux showed exceptional catalytic activity for the reduction of nitroarenes to the corresponding azoxy compounds exclusively in the presence of hydrazine monohydrate.However when nickel nitrate hexahydrate was replaced by nickel chloride dihydrate with zinc, only the aminoarenes were formed in high yields.With unactivated catalyst, the reduction reaction from a mixture of nitroarenes, nickel nitrate or chloride, excess zinc and hydrazine monohydrate gave the corresponding azo, azoxy and amino compounds in much lower yields.
