Platinum nanoparticles supported on zirconia mediated synthesis of N-acyl and N-(tert-butoxycarbonyl)amines from nitroarenes and azides

Direct Access to Amides from Nitro-Compounds via Aminocarbonylation and Amidation Reactions: A Minireview

The ubiquity of the amide bond in functional molecules including proteins, natural products, pharmaceuticals, agrochemicals and materials provides impetus to design and develop newer strategies for the generation of this linkage. Owing to growing awareness about sustainability and development of benign strategies, the traditional route of synthesis of amides via reaction between carboxylic acids and amines in the presence of stoichiometric amount of coupling reagents is tagged to be harsh and wasteful. In one of the unconventional routes, nitro compounds are used directly as amine surrogates for preparing amides mostly via aminocarbonylation and amidation reactions. Typically, such processes involves nitroarenes owing to their propensity to transform into nitroso, hydroxylamine, diazo, hydrazine or aniline intermediates in situ under the influence of suitable catalyst or oxidant. This short review provides the comprehensive overview of these reactions including insight into the scope and their mechanisms.

Fe-mediated synthesis of N-aryl amides from nitroarenes and acyl chlorides

Amides are prevalent in nature and valuable functional compounds in agrochemical, pharmaceutical, and materials industries. In this work, we developed a selective and mild method for the synthesis of N-aryl amides. Starting from commercially available nitroarenes and acyl halides, N-aryl amides with good yields can be obtained in water. Especially in the process of transformation, Fe dust is the only reductant and additive, and the reaction can be easily performed on a large scale.

Amides are prevalent in nature and valuable functional compounds in agrochemical, pharmaceutical, and materials industries.

Highly efficient Cu(ii)-pyrazoledicarboxylate heterogeneous catalysts for a base-free aerobic oxidation of benzylic alcohol to benzaldehyde with hydrogen peroxide as the oxidant

A Cu(ii)-pyrazoledicarboxylate MOF displayed high activity and selectivity in the base-free oxidation of benzyl alcohol to benzaldehyde combined with H₂O₂.

Tin(ii) chloride dihydrate/choline chloride deep eutectic solvent: redox properties in the fast synthesis of N-arylacetamides and indolo(pyrrolo)[1,2-a]quinoxalines

In this contribution a physicochemical, IR and Raman characterization for the tin(ii) chloride dihydrate/choline chloride eutectic mixture is reported. The redox properties of this solvent were also studied by cyclic voltammetry finding that it can be successfully used as an electrochemical solvent for electrosynthesis and electroanalytical processes and does not require negative potentials as verified by the reduction of nitrobenzene. The potential use of this eutectic mixture as a redox solvent was further explored in obtaining aromatic amines and N-arylacetamides starting from a wide variety of nitroaromatic compounds. In addition, a fast synthetic strategy for the construction of a series of indolo(pyrrolo)[1,2-a]quinoxalines was developed by reacting 1-(2-nitrophenyl)-1H-indole(pyrrole) with aldehydes. This simple protocol offers a straightforward method for the construction of the target quinoxalines in short reaction times and high yields where the key step involves a tandem one-pot reductive cyclization-oxidation.

Physicochemical and redox properties of SnCl₂·2H₂O/ChCl deep eutectic solvent were studied and applied in the synthesis of anilines, N-arylacetamides and indolo(pyrrolo)[1,2-a]quinoxalines starting from nitroaromatic compounds.

Photocatalytic synthesis of anilides from nitrobenzenes under visible light irradiation: 2 in 1 reaction

An efficient method has been developed for the synthesis of a series of anilides via a two in one reaction of nitrobenzenes with anhydride in the presence of TiO2 as a nanocatalyst and photocatalyst under sunlight or blue LED irradiation. In this method simultaneously, nitrobenzenes convert to the corresponding anilines via photocatalytic reduction on the TiO2 surface, and a condensation of aniline with the anhydride performed on the Lewis acid site of the TiO2 surface. Interestingly amidation step leads to the promotion of better reaction and good selectivity in reduction of nitrocompounds. This method is simple, rapid, high yield, and green.

The hydrogenation of nitroarenes mediated by platinum nanoparticles: an overview

This review reports the most recent advances in the synthesis and application of platinum nanoparticles as catalysts in the hydrogenation reaction of nitroaromatics.