Eco‐friendly magnetic clinoptilolite containing Cu(0) nanoparticles (CuNPs/MZN): as a new efficient catalyst for the synthesis of propargylamines via A³ and KA² coupling reactions

Abstract

In this reaserch a new and eco-friendly magnetic catalyst for the synthesis of propargylamines is reported. Initial incorporation of Fe 3 O 4 magnetic nanoparticles (MNPs) into the pores of the natural clinoptilolite zeolite followed by modification with epichlorohydrine and ethylenediamine and then immobilization of CuNPs on the surface of functionalized zeolite gave the desired catalyst (CuNPs/MZN). The CuNPs/MZN was fully characterized by various techniques such as FT-IR, CHN, TGA, ICP, XRD, SEM, TEM and BET. A host of propargylamines were readily synthesized through using the catalyst in high yields and short reaction times via A 3 and KA 2 coupling reactions of aldehydes/ketones, amines, and phenylacetylene. The CuNPs/MZN was easily separated from the reaction mixture by an external magnet and reused several times successfully. The catalyst has the potential for catalysis of various organic transformations.

Design, Synthesis, and Characterization of a Novel Magnetically Recoverable Copper Nanocatalyst Containing Organoselenium Ligand and Its Application in the A3 Coupling Reaction

“…According to the reaction mechanisms proposed in the literature, − the probable mechanism in the presence of Fe 3 O 4 @SiO 2 -Se-T/CuI was outlined in Scheme . As seen in Scheme , in the first step, the terminal alkyne is inserted in the immobilized copper species on the surface of Fe 3 O 4 @SiO 2 -Se-T to create the Cu acetylide as an intermediate (I) with the activation of the terminal carbon–hydrogen bond of phenylacetylene.…”

Solvent-Free A3 and KA2 Coupling Reactions with mol ppm Level Loadings of a Polymer-Supported Copper(II)–Bipyridine Complex for Green Synthesis of Propargylamines

“…The three-component coupling of aldehydes or ketones with amines and alkynes, commonly known as A 3 or KA 2 coupling, is a direct and convenient protocol for the synthesis of propargylamines, which are useful and versatile intermediates for the preparation of natural products and bioactive compounds. − In the pursuit of green sustainable chemistry, various supported copper catalysts have been developed for the solvent-free three-component coupling reaction, with high recyclability. − However, most catalytic conditions require a catalyst loading at a mol % level. Even if recycling runs using a mol % quantity of the recovered catalysts can be repeated successfully several times under solvent-free conditions, the cost of the catalyst-recycling process is still high.…”

“…Moreover, the range of applicable carbonyl substrates is usually limited to aldehydes. Due to the low reactivity of ketones, only a few supported copper catalysts with mol % loadings are capable of successfully promoting the solvent-free KA 2 coupling of ketones, amines, and alkynes. − Therefore, the development of extremely efficient copper catalysts that promote both A 3 and KA 2 coupling reactions at mol ppm catalyst loadings under solvent-free conditions is undoubtedly desired to achieve an ideal and practical catalytic synthesis of propargylamines with a high level of green sustainability.…”