CuCl heterogenized on metformine-modified multi walled carbon nanotubes as a recyclable nanocatalyst for Ullmann-type C–O and C–N coupling reactions

Abstract

Herein, a novel MWCNTs-Met/CuCl nanocatalyst synthesis method by metformine covalent grafting on the surface of carbon nanotubes and subsequent coordination with a CuCl catalyst is described.

Biochar as heterogeneous support for immobilization of Pd as efficient and reusable biocatalyst in C–C coupling reactions

“…This model reaction was investigated in the presence of various amounts of Pd(0)-TBA@biochar Table 1, lower amounts of Pd(0)-TBA@biochar led to a lower yield of product (Table 1, entry 2) and also a higher amount of this catalyst gave no significant improvement in the time or yield of reaction (Table 1, entry 4). In the final step, the effect of temperature on the model reaction was studied, and the best results were obtained at 80°C (Table 1, entries [11][12][13]. Based on the obtained results, PEG-400 as solvent and sodium carbonate (Na 2 CO 3 ) as base gave the best conversion of starting materials to products.…”

“…To optimize the Suzuki coupling reaction, the reaction of 4-iodotoluene with PhB(OH) 2 was selected as a model reaction. This model reaction was investigated in the presence of various amounts of Pd(0)-TBA@biochar [5][6][7][8][9][10][11]. Based on the obtained results, PEG-400 as solvent and sodium carbonate (Na 2 CO 3 ) as base gave the best conversion of starting materials to products.…”

“…[5][6][7] When the size of particles is decreased, their surface area is increased, which will be lead to high capacity of catalyst loading. [1][2][3][4][5][6][7][8] For example, iron oxide, [9] mesoporous silica materials, [10] carbon nanotubes, [11] ionic liquids, [12] polymers, [13] graphene oxide, [14,15] heteropolyacids, [16] boehmite nanoparticles, [17] etc., have been used as catalyst supports; however, all of these materials require chemical procedures and chemical starting materials for their preparation which are expensive and not environmentally friendly. [1][2][3][4][5][6][7][8] For example, iron oxide, [9] mesoporous silica materials, [10] carbon nanotubes, [11] ionic liquids, [12] polymers, [13] graphene oxide, [14,15] heteropolyacids, [16] boehmite nanoparticles, [17] etc., have been used as catalyst supports; however, all of these materials require chemical procedures and chemical starting materials for their preparation which are expensive and not environmentally friendly.…”

Functionalization of multi‐walled carbon nanotubes by the baclofen drug to immobilize palladium nanoparticles and catalyze Sonogashira coupling reactions

“…This method introduces ‐COOH groups onto the surface of MWCNTs and creates MWCNT‐COOH. It should be noted the ‐COOH functionalized CNTs can be further modified by reacting the ‐COOH groups with various organic molecules including biomolecules, for example, drugs, vitamins, amino acids, carbohydrates and proteins . A potential candidate for modification of MWCNT‐COOH is baclofen.…”

“…It should be noted the -COOH functionalized CNTs can be further modified by reacting the -COOH groups with various organic molecules including biomolecules, for example, drugs, vitamins, amino acids, carbohydrates and proteins. [8][9][10][11] A potential candidate for modification of MWCNT-COOH is baclofen. This lipophilic drug is a gamma-aminobutyric acid (GABA) derivative that acts as a GABA-B agonist, inhibits the activity of presynaptic motor neurons, and results in an antispastic response.…”