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CO2 fixation reactions by inserting it in reactive organic compounds are very challenging for the utilization of this abundant and harmful gas present in air and thus to mitigate this greenhouse gas responsible for global warming. This can be achieved by appropriate design of functionalized porous nanocatalysts having high surface areas and porosity and good CO2 uptake capacity. Herein, we first report the decoration of silver nanoparticles (NPs) over the surface of a covalent organic framework (COF) material TpPa-1 synthesized through the polycondensation of 2,4,6-triformylphloroglucinol (TFP) and p-phenylenediamine. The resulting material Ag@TpPa-1 was thoroughly characterized by N2 adsorption/desorption, powder X-ray diffraction (PXRD), FE-SEM, TEM, UV-Vis, FT IR and thermogravimetric techniques. This Ag NP decorated porous COF in the presence of DBU exhibited excellent catalytic activity for the synthesis of tetramic acids from a variety of propargylic amine derivatives at 60 °C under atmospheric pressure of carbon dioxide via formation of oxazolidinones, where CO2 acts as a C1 reagent. The Ag@TpPa-1 catalyst exhibited excellent recycling efficiency for the synthesis of tetramic acid with no leaching of Ag from the catalyst surface. [ABSTRACT FROM AUTHOR]

Two very important catalytic transformations for CO2 in recent years are terminal alkyne carboxylation and amine formylation. Hydrothermal and impregnation methods have been used to produce nanoporous ZnO and CuBr/ZnO materials respectively. The materials are characterized by different characterization methods like PXRD, FTIR, FESEM, TEM, TG‐DTA and EDAX. The CuBr/ZnO material showed flowerlike morphology with nanoporous nature and also showed excellent catalytic activity towards synthesis of different propiolic acids and N‐formylated amines under 1 atmospheric pressure of CO2 at gentle reaction conditions with selectively high yields for the desired products. The CuBr/ZnO material showed good recycling efficiency as a promising and cheap heterogeneous catalyst upto 5 reaction cycles with negligible amount of catalyst deactivation for both the reactions. CO2 fixation via carboxylation of terminal alkynes and formylation amines: Nanoporous zinc oxide supported CuBr material is prepared through impregnation method and the material is well characterized. The material is very efficient for the fixation of CO2 through carboxylation of terminal alkynes and N‐formylation formation reactions of amines under very mild reaction conditions. [ABSTRACT FROM AUTHOR]

Environmentally benign and highly stable magnetic nano powder of NiFe2O4 was synthesized and characterized by XRD, HRTEM, EDX and Nitrogen BET adsorption isotherm analysis. Also, XPS analysis confirmed the electronic environment as well as the oxidation state of the elements. The NiFe2O4 catalyst was exploited in one‐pot three‐component synthesis of spiro[indoline‐3,3′‐pyrrolizine] and spiro[indoline‐3,5′‐pyrrolo[1,2‐c]thiazole] scaffolds, because of its ditopic nature which can provide both acidic (Fe3+) and basic (O2−) properties, require for the reactions. The desirability of this methodology resides in its simplicity, environmental friendliness, cost effectiveness and easier scaling up for bulk synthesis. Water was utilised as a medium for synthesis of the catalyst as well as the medium of the reaction leading to the product. The synthesized NiFe2O4 nanocatalyst can be recycled upto six times without any significant loss of activity. An efficient recyclable ditopic heterogeneous catalytic behaviour of nano‐sized NiFe2O4 for the one pot synthesis of spiro[indoline‐3,3′‐pyrrolizine] and spiro[indoline‐3,5′‐pyrrolo[1,2‐c]thiazole] moieties in aqueous medium. [ABSTRACT FROM AUTHOR]

We report a new highly crystalline 2D π-conjugated hexagonal mesoporous covalent organic framework material, TrzCOF, through the solvothermal polycondensation of 1,3,5-tri(4-formylbiphenyl) benzene [Ph7(CHO)3, TFBPB] with 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (TAPT) and it displayed excellent anticancer activity for human colorectal carcinoma HCT-116 cells. [ABSTRACT FROM AUTHOR]

A convenient approach for the synthesis of 4,4′-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) by an efficient one-pot reaction of aromatic aldehydes, phenylhydrazine, and ethyl acetoacetate by using substoichiometric amount of K2CO3in acetonitrile solvent at room temperature is described. This protocol of one-pot synthesis produced a library of bis-pyrazolylmethane derivatives, a potential bioactive compound in very good to excellent yields. [ABSTRACT FROM AUTHOR]

A simple protocol is developed for the conversion of various substrates into highly functionalized propanone frameworks. [ABSTRACT FROM AUTHOR]

An efficient reaction of o-phenylenediamines with terminal acetylenes is achieved under mild conditions to give benzodiazepinones (III) in moderate to good yields. [ABSTRACT FROM AUTHOR]

CO2 fixation reactions by inserting it in reactive organic compounds are very challenging for the utilization of this abundant and harmful gas present in air and thus to mitigate this greenhouse gas responsible for global warming. This can be achieved by appropriate design of functionalized porous nanocatalysts having high surface areas and porosity and good CO2 uptake capacity. Herein, we first report the decoration of silver nanoparticles (NPs) over the surface of a covalent organic framework (COF) material TpPa-1 synthesized through the polycondensation of 2,4,6-triformylphloroglucinol (TFP) and p-phenylenediamine. The resulting material Ag@TpPa-1 was thoroughly characterized by N2 adsorption/desorption, powder X-ray diffraction (PXRD), FE-SEM, TEM, UV-Vis, FT IR and thermogravimetric techniques. This Ag NP decorated porous COF in the presence of DBU exhibited excellent catalytic activity for the synthesis of tetramic acids from a variety of propargylic amine derivatives at 60 °C under atmospheric pressure of carbon dioxide via formation of oxazolidinones, where CO2 acts as a C1 reagent. The Ag@TpPa-1 catalyst exhibited excellent recycling efficiency for the synthesis of tetramic acid with no leaching of Ag from the catalyst surface.