A New Approach for the Synthesis of Bis(3-Indolyl)Pyridines via a Cooperative Vinylogous Anomeric Based Oxidation Using Ammonium Acetate as a Dual Reagent-Catalyst Role under Mild and Green Condition

Catalytic Application of Functionalized Bimetallic–Organic Frameworks with Phosphorous Acid Tags in the Synthesis of Pyrazolo[4,3-e]pyridines

“…Based on the concept of the modified strategy of MOFs in the design and synthesis of new catalysts in our group research, − we have presented a new porous catalyst based on bimetal–organic frameworks (bimetal–MOFs). In the following, phosphorous acid tags have been used to decorate the bimetallic–organic frameworks, which have created acidic sites for increasing their catalytic activity.…”

“…The postmodification method has been considered for designing various catalysts based on metal–organic frameworks (MOFs). In this method, MOFs are assembled and modified with various chemical reagents while their structure and network remain intact. − Our research groups have introduced a new category of acidic catalysts and/or reagents via a postmodification methodology for inserting phosphorous acid tags on the surface of metal–organic frameworks, − mesopores, , melamine, carbon quantum dots, , glycoluril, and uric acid . Phosphorous acid as a catalyst has been used for the oligomerization of light olefins, destructive alkylation of hydrocarbons, and organic synthesis .…”

“…MOFs, in particular, are synthesized by combining metal clusters and organic compounds as nuclei and ligands, respectively. These materials offer unique properties and structures that make them highly attractive for various applications as catalysts, gas storage, and separation processes. − It is known that two-dimensional (2D) and three-dimensional (3D) porous structures have distinctive features such as tunable pore size, diverse structure, large surface area, and tunable chemistry. − Metal–organic frameworks are widely used in various fields such as gas separation, drug delivery, energy storage, and catalyst. − Also, the catalytic activities of metal–organic frameworks include photocatalysis, , asymmetric catalysis, , supramolecular catalysis, , oxidation of materials, biomass conversion, , electrocatalysis, , acidic and basic catalysis, − separation of toxic substances from different phases, medical, biological, sensors, and solar cells. , Metal–organic frameworks based on a combination of two metals have better stability and properties than single-metal MOFs. − The synergistic effect achieved by incorporating two metals in bimetallic MOFs can significantly enhance their catalytic activity. As a result, the synthesis of bimetallic MOFs has emerged as an attractive approach in this field, offering new avenues for exploration.…”

Application of Metal–Organic Frameworks with Sulfonic Acid Tags in the Synthesis of Pyrazolo[3,4-b]pyridines via a Cooperative Vinylogous Anomeric-Based Oxidation

“…This concept explains the stereoelectronic interactions in the preparation of structures comprising a heteroatom. − The term anomeric-based oxidation (ABO) has been introduced for the formation of final products from susceptible intermediates via sharing lone pair electrons of nitrogen atoms with the anti-bonding orbitals of the C–H bond ( n N → σ* C–H ). − This concept has been used as a novel strategy for the oxidation of compounds in the absence of oxidizing agents. , Stereoelectronic effects also have a major role in the oxidation–reduction of susceptible biological compounds such as NADPH/NADP + (Figure ). Recently, the unique phrase “cooperative vinylogous anomeric-based oxidation” (CVABO) has been introduced for the synthesis of heterocycle compounds. − ,− …”

Ammonium acetate as a Dual Reagent-Catalyst Role in Efficient Synthesis of 2,4,6-Trisubstituted 1,3,5-triazines from Aldehydes

“…For the synthesis of 2,4,6-trisubstituted 1,3,5triazines 15 , Liu and colleagues recently reported theFe-catalyzed cyclization of aldehydes with NH 4 I as the sole nitrogen source. There are many accounts in the literature [17][18][19][20][21][22][23][24][25][26] about the widespread usage of ammonium acetate (NH 4 OAc) as a nitrogen source in chemical synthesis. In this succinct statement, we show that the cyclotrimerization of aldehydes can utilize NH 4 OAc as the only nitrogen source.…”