One-Pot Synthesis of Aminoindolizines and Chalcones Using CuI/CSP Nanocomposites with Anomalous Selectivity under Green Conditions

Abstract

CuI/CSP nanocomposites were found to be efficient and recyclable nanocatalysts for one-pot synthesis of aminoindolizines via A3 coupling reaction in the presence of ethylene glycol (EG) as a recyclable solvent. In contrast, chalcones were isolated when the reaction was performed in the presence of secondary amines such as piperidine, 3-methylpiperidine, pyrrolidine, and piperazine under solvent free conditions. The CuI/CSP was recycled for five times without significant loss in its catalytic activity. The anomalous selectivity in the formation of aminoindolizines and chalcones was dependent on solvents and secondary amines used for the reaction. The present methodology is facile and follows green principles with higher atom economy (94%) and smaller E-factor (0.06).

ZnO Nanoparticles Embedded on a Reduced Graphene Oxide Nanosheet (ZnO−NPs@r‐GO) as a Proficient Heterogeneous Catalyst for a One‐Pot A3‐Coupling Reaction

“…[31] Though for organic transformations, [43][44] ZnO nanoparticles (NPs) have been established as solitary heterogeneous catalysts however, to the best of our knowledge, only few reports on rGO/ZnO nanocomposites as catalysts have been reported in the literature. [45][46][47] In continuation of our earlier work [48][49][50] , here in we report highly efficient ZnOÀ NPs@r-GO as a proficient heterogeneous catalyst and substantiated through various characterization tools. The accountability of rGO in ZnOÀ NPs@r-GO nanocatalyst is mainly providing tangible support which enhances the mechanical strength of the catalyst and also uniform dispersibility of ZnOÀ NPs.…”

Copper‐Catalysed Multicomponent Syntheses of Heterocycles

“…A green CuI/CSP (carbon spheres) catalysed one‐pot A 3 coupling for the synthesis of aminoindolizines in ethylene glycol (EG) was reported . Chalcones were isolated when secondary amines such as 3‐methylpiperidine, piperidine, piperazine and pyrrolidine were reacted under solvent‐free conditions.…”

Fabrication of Copper‐based Silica‐coated Magnetic Nanocatalyst for Efficient One‐pot Synthesis of Chalcones via A3 Coupling of Aldehydes‐Alkynes‐Amines

“…Alonso and group have synthesized the desired chalcones in excellent yields by using heterogeneous CuNPs/C nanocatalyst . Similarly, another group reported copper immobilized carbon spheres nanocomposites (CuI/CSP) . But, unfortunately, these methodologies require cumbersome filtration and centrifugation techniques for the recovery of catalyst.…”