Porous triazine polymer: A novel catalyst for the three‐component reaction

Abstract

A new porous triazine-based covalent organic polymer (Triazine-COP) was prepared through the Schiff-base condensation of 2,4,6-tris(4-formyl phenoxy)-1,3,5-triazine and 4,4 0-oxydianiline, under sonication. The synthesized Triazine-COP with a high surface area was stable in water and other organic solvents. In the next step, Au (III) ions were immobilized on the nitrogen-rich Triazine-COP that on the reduction with NaBH 4 produced the heterogeneous catalyst of gold clusters in nanosize (Au-NCs@Triazine-COPs). It was applied as an efficient catalyst for the A 3 coupling reaction of alkynes, aldehydes with and amines. Both electron-withdrawing/releasing groups produced the corresponding propargylamines with high yields. The high activity of the Au-NCs@Triazine-COPs in this reaction was because of the nanoporous structure of the support that enables the high dispersion and an unhindered open environment for the NCs. The catalyst was reused up to 7 times without significant loss in activity.

Single-pot tandem oxidative/C–H modification amidation process using ultrasmall PdNP-encapsulated porous organosilica nanotubes

“…In line with the development of sustainable protocols and inspired by our previous work on the catalytic application of solid-based catalysts and porous materials (PMO, SBA-15, and MOF) in organic reaction transformations, 31,34,52,53,55–65 especially the synthesis of amides, 66–70 herein, we describe a one-pot tandem oxidative amidation reaction using Pd NPs @B-SNTs as an active catalyst and H 2 O 2 as a green oxidant for the synthesis of primary, secondary, and tertiary amides. The catalytic activity domain of Pd NPs @B-SNTs for the synthesis of amides using various structural compounds (primary aromatic and aliphatic alcohols, amine salts, and NH 2 OH·HCl) through oxidative amidation was evaluated.…”

“…The binding energy range of 335–341 eV is correlated to Pd 3d 5/2 and Pd 3d 3/2 of metallic Pd, while the component at 338–344 eV is related to PdO owing to the partial oxidation of the Pd NPs . 55,56 The surface area, pore volume and diameter of the B-SNTs and Pd NPs @B-SNTs are calculated based on the Brunauer–Emmett–Teller (BET) equation (Table 1).…”

Recent advances in the design, synthesis and catalytic applications of triazine-based covalent organic polymers

“…15). 127 Thereafter, the newly-synthesised triazine-COP was immobilized with gold nanoclusters and designated as Au-NCs@Triazine-COPs. The newly-synthesised Au-NCs@Triazine-COPs were then employed as the catalyst for the synthesis of propargylamines using alkynes, aldehydes, and amines via an A 3 coupling reaction.…”

“…Fig 15. Synthesis of Au-NCs@Triazine-COP and its catalytic application in A 3 -coupling reactions 127. (Reproduced from ref 127.…”

Gold Nanoparticle-Catalyzed Multicomponent Reactions

“…Propargylamines are building blocks, key intermediates, and synthetically versatile components for the synthesis of N- containing biological active structures including oxotremorine analogues, β-lactams, peptides, natural products, and therapeutics drug molecules . Gold, including GNPs, salts, and complexes, being a class of efficient catalysts, has garnered widespread attention in A 3 -coupling reactions. − In this perspective, we focus on the preparation of propargylamines via a transition metal-catalyzed A 3 -coupling reaction in the presence of GNPs. − In this context, the first paper concerning GNP-catalyzed greener preparation of propargylamines was explored by Kidwai and colleagues via an A 3 -coupling reaction of 3CR amine, alkyne, and aldehyde; products were obtained in the presence of 10 mol % GNPs in 67%–96% yield. The particle size of the catalyst was a key issue in this reaction, and the maximum reaction rate has been achieved when the particles of average size were ∼20 nm …”