Mohit Tripathi

Ethylenediammonium diformate (EDDF) in PEG600: an efficient ambiphilic novel catalytic system for the one-pot synthesis of 4H-pyrans via Knoevenagel condensation

A novel ethylenediammonium diformate–polyethylene glycol (EDDF-PEG600) system was developed as a catalyst for the Knoevenagel condensation and Knoevenagel initiated three-component one-pot synthesis of 4H-pyrans at room temperature with high yields and in short reaction times. Further, the EDDF-PEG600 catalytic system was recycled six times without any appreciable loss in its activity and hence can be termed as a green, environmentally benign catalytic system. A plausible mechanism depicting the ambiphilic nature of EDDF (catalyst) and PEG (promoting medium) acting in synergy has been proposed.

CuI nanoparticles mediated expeditious synthesis of 2-substituted benzimidazoles using molecular oxygen as the oxidant

A general and easy method for the synthesis of several 2-substituted benzimidazoles from cyclization of o-diaminobenzenes and various aldehydes using CuI nanoparticles as a heterogeneous catalyst is described. Short reaction times, easy and quick isolation of the products and excellent yields are the main advantages of this procedure. This CuI nanoparticles catalyst system was found to be air/O2 stable and also used for large scale cyclization reaction with recoverable and reusable properties without loss of catalytic activity for upto six cycles.

4-Aminoquinoline-pyrimidine-aminoalkanols: synthesis, in vitro antimalarial activity, docking studies and ADME predictions

Twenty-four new 4-aminoquinoline-pyrimidine hybrids containing a terminal aliphatic amino-alcohol chain were synthesized and assessed for their antimalarial activity against chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum. All of the compounds displayed potent antiplasmodial activities (IC50 values in the range of 0.05–10.47 μM) with no appreciable cytotoxicity towards mammalian cells, up to the highest tested concentration of 12 μM. Molecular docking studies of the most active compounds (8b–8f, 8u and 8v) with both wild type and quadruple mutant Pf-DHFR-TS were performed, which exhibited interactions comparable to conventional folate inhibitors. ADME predictions also revealed favourable pharmacokinetic parameters for the synthesized hybrids, which warrants their suitability for development as potent antimalarials.

Facile construction of 3-indolochromenes and 3-indoloxanthenes via EDDF catalyzed one-pot three component reactions

A novel and green strategy for the construction of biologically relevant 3-indolochromene and 3-indoloxanthene scaffolds is reported using EDDF as a catalyst and ethylene glycol as a promoter solvent. The catalytic system offers wider applicability, crossing over a variety of substrates, besides affording exclusively the desired product in shorter reaction times and high yields. Furthermore, the ease of work-up and purification combined with the recyclability of the EDDF–ethylene glycol system makes the present method environmentally sustainable and amenable to large-scale synthesis as well.

Chemoselective Hydrazine‐mediated Transfer Hydrogenation of Nitroarenes by Co3O4 Nanoparticles Immobilized on an Al/Si‐mixed Oxide Support

Cobalt oxide nanoparticles (size 2 to 3.5 nm) were successfully impregnated on an alumina-silica (mixed oxide) support through an experimentally viable and easily reproducible protocol. The prepared material was well characterized by XRD, HR-TEM, BET surface area, EDX and XPS analyses. Porous alumina-silica having a high surface area served as a protective heterogeneous support on which the well-dispersed Co3 O4 nanoparticles served as an active catalytic species for the hydrazine-mediated transfer hydrogenation of nitroarenes. About 2 mol % of the active catalyst in ethanol at 60 °C was adequate for a successful conversion. Moreover, transfer hydrogenation of nitroarenes by the catalyst was found to take place chemoselectively in the presence of other labile functional groups such as halide, alkene, nitrile, carbonyl, and ester. This inexpensive catalyst was also able to catalyze the reaction on a gram scale reaction and found to be robust and recyclable up to eight runs.