Highly Selective Catalytic Reduction of Nitro- to Azoarenes under Ambient Conditions

Abstract

Catalytic system of Au nanoparticles supported on metal oxides has been developed to produce azoarenes in one-step directly from nitroarenes under mild conditions (30°C, 1 bar of N 2) using 2-propanol as solvent and reducing agent. Close to 100 % chemoselectivity to substituted azoarenes with different functional groups left intact and close to quantitative yields make this procedure promising for the production of azoarenes.

Design, Synthesis, and Biological Evaluation of Axitinib Derivatives

“…There are a lot of synthetic methods to make aromatic azo compounds, but for asymmetric aromatic azo compounds, diazo-reaction, and nitroso-amino coupling reaction are the main choices [ 10 , 11 , 12 ]. Nitroso compounds are usually unstable because of easily oxidized, and it is also difficult to obtain through oxidizing amino compounds or reducing nitro-compounds.…”

“…Nitroso compounds are usually unstable because of easily oxidized, and it is also difficult to obtain through oxidizing amino compounds or reducing nitro-compounds. The diazo-reaction has the advantages of reacting rapidly, high yield, wide application range, easy operating and so on, so diazo-reaction was adopted to build target compounds [ 10 , 11 ].…”

Synthesis of Pd/SBA-15 catalyst employing surface-bonded vinyl as a reductant and its application in the hydrogenation of nitroarenes

“…Owning to their unique structures and high activity, the synthesis of supported palladium nanoparticles is of great signicance in heterogeneous catalysis. [1][2][3] Numerous methods have been developed to prepare these catalysts, which have been widely used in hydrogenation, [4][5][6][7][8] hydrogenolysis, [9][10][11][12] decarbonylation, 13,14 coupling reactions, [15][16][17][18] oxidation, 19 and so on. [20][21][22][23] The synthesis of supported palladium nanoparticles usually involves a palladium salt as the palladium source to be reduced to palladium(0) by a reducing agent, such as H 2 , formic acid or glycol.…”

Microbial Synthesis of Gold Nanoparticles and Their Applications as Catalysts

“…In a report by Carlos et al gold nanoparticles supported on hydrotalcite (magnesiumaluminum hydroxycarbonate) prepared for the hydrogenation of nitroaromatic compounds were obtained by the coprecipitation procedure. During this multistep process, heating (80°C), isopropanol (solvent), and nitrogen atmosphere were employed [42].…”

“…Different support matrices, namely, magnesium oxide, rutile (TiO 2 ), SiO 2 coated branched polyethyleneimine, and chitosan-grafted graphene oxide, are used for the preparation of heterogeneous catalysts for the hydrogenation of nitroarenes. Recent methodologies reported to synthesize aryl amines show the requirement of toxic metal catalysts [48], inflammable toxic solvents [49][50][51], heating [52,53], and inert conditions [41,42] which are not environmentally benign.…”