An efficient, green, and sustainable synthesis of new hybrid molecules containing flavanone with triazole by merging the Michael addition and Click reaction using a copper oxide/reduced graphene oxide nanocomposite in one pot is reported. The catalyst can easily be recycled and reused in seven consecutive runs without compromising the product yields. Other notable advantages include using water as a reaction medium and obtaining good to excellent yields, low catalyst loading, high atom efficiency, high substrate variation, and good results in the gram scale reaction.

We report a sustainable and metal free carbocatalyst, graphite oxide, for the synthesis of 1,5-benzodiazepines under room temperature and solvent free heating conditions.

Visible‐light‐induced reactions have allowed researchers to attain unorthodox bond formation and elusive chemical processes under mild and inherently safe reaction conditions. However, these methods have relied heavily on Ru‐ and Ir‐based complexes or metal‐free chromophores. While the heavy transition metal complexes are limited by their high cost, toxicity, and adverse environmental effects. Metal‐free photo‐redox catalysts are restricted due to their poorer photo‐stability. In order to overcome these shortcomings, extensive research aimed towards utilizing 3d‐transition metals has come to the forefront. Manganese, in this regard, holds great promise as a versatile and economically sustainable 3d‐transition metal catalyst. Hence, it is not surprising that recent years have witnessed several advances in visible‐light‐mediated manganese catalysis in areas of organic, polymer, and materials chemistry. Manganese‐based heterogeneous systems have also been utilized to effect dimerization and oxygenation reactions showcasing the versatility of manganese. Moreover, manganese has enabled late‐stage functionalization of valuable medicinal compounds and natural products, which are all important from the viewpoint of medicinal and pharmaceutical chemistry. In the present review, comprehensive discussions on the advances, significance, approaches, and mechanistic aspects have been added for each photochemical reaction process. Further, the reaction scope, limitations, and future prospects of visible‐light‐induced manganese catalysis have also been reviewed.

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Graphite oxide, a green metal-free carbocatalyst, has been successfully exploited for the library synthesis of biologically active pyrimidine derivatives. Reaction was carried out under solvent-free reaction conditions (SFRC) thereby reducing the application of hazardous chemicals and solvents. The present catalytic system eliminates the risk of metal contamination in the product which is viable for pharmaceutical industries and showed better catalytic activity under sustainable conditions compared to other classical catalytic systems. The catalyst, being heterogeneous in nature, can be easily recycled and reused up to nine consecutive runs without much decrease in catalytic activities thereby increasing sustainability of the procedure. Diversity in the formation of pyrimidine moieties has been exhibited with the tolerance of a large number of functional groups establishing the generality of this reaction. A few other cutting edge advantages of the present one-pot multicomponent methodology are high atom economy, low catalyst loading, milder reaction conditions, higher yield of the desired product, simple work up procedure, easy handling of the catalyst, etc. The present methodology showed good results in gram scale conditions thereby indicating its applicability in academic as well as industrial settings in the near future.

Nano-organocatalyzed one-pot four-component reactions for the synthesis of phthalazine-trione/dione derivatives have been devised for the first time from easily accessible starting materials under solvent-free conditions.

Graphite oxide was synthesized and subsequently decorated with Ru-ferrite NPs which was characterized properly. The graphite oxide was reduced upon embedding of Ru-ferrite NPs, which is reflected in powder XRD, TGA, FT-IR, and Raman analyses. The paramagnetic nature of RuFG was confirmed from VSM analysis which particularly makes it a recyclable candidate in catalysis. The prepared RuFG was successively utilized for the conversion of aromatic aldehyde or nitrile to the corresponding primary amides in aqueous medium. The RuFG catalyst proved to be highly efficient providing excellent yields within a short period of time. The catalyst could be recycled and reused for eight consecutive runs without significant loss in catalytic activity. ICP-AES analysis of the reused catalyst confirmed insignificant leaching. TON (270) and TOF (270 h–1) calculations of the present RuFG catalyst show superiority from that of the reported metal-supported heterogeneous catalyst.

An efficient magnetically retrievable ferrite-supported glutathione nano-organocatalyst has been employed for the synthesis of a library of 2-amino-4H-pyran derivatives in aqueous medium via one-pot, multicomponent reaction. The highlight of this protocol lies in its operational simplicity, use of greener solvent, high yield within very short period of time and reusability of the catalyst. This method provides an alternative greener approach for the synthesis of 2-amino-4H-pyran derivatives.