Pd(II) salen complex covalently anchored to multi‐walled carbon nanotubes as a heterogeneous and reusable precatalyst for Mizoroki–Heck and Hiyama cross‐coupling reactions

Abstract

A Pd(II) salen complex anchored to multi-walled carbon nanotubes showed excellent catalytic activity and stability for the Mizoroki-Heck and Hiyama cross-couplings of aryl halides with olefins and phenylsiloxanes. Furthermore, the heterogeneous catalyst could be reused up to four times with the catalytic activity being recovered easily after simple manipulations.

Carbon‐Derived Supports for Palladium Nanoparticles as Catalysts for Carbon‐Carbon Bonds Formation

“…In 2016, Movassagh and co‐workers employed Pd‐Salen@MWCNT catalyst (Scheme ) for the acylation reaction of arylboronic acids with aroyl chlorides . This catalyst previously was prepared and applied by same group in Suzuki, Sonogashira, Heck and Hiyama reactions ,. The acylation reaction was performed with 0.9 mol % Pd loading, K 2 CO 3 as a base in aqueous acetone at 50 °C affording the corresponding diaryl ketones in 71 to 94 % yields (Scheme ).…”

“…[87] This catalyst previously was prepared and applied by same group in Suzuki, Sonogashira, Heck and Hiyama reactions. [72,79] The acylation reaction was performed with 0.9 mol % Pd loading, K 2 CO 3 as a base in aqueous acetone at 50°C affording the corresponding diaryl ketones in 71 to 94 % yields (Scheme 16). The catalyst can be easily recovered by a simple filtration and reused for three consecutive runs without significant loss of its activity with 1.2 % of Pd leaching.…”

Immobilized Pd on (S)‐methyl histidinate‐modified multi‐walled carbon nanotubes: a powerful and recyclable catalyst for Mizoroki–Heck and Suzuki–Miyaura C–C cross‐coupling reactions in green solvents and under mild conditions

“…Multi‐walled carbon nanotubes (MWCNTs) are some of the ‘hottest' nanomaterials in synthesis, characterization and applications due to their unique thermal, mechanical and chemical properties . In addition, MWCNTs can be used as very good catalyst supports because of their high surface area and insolubility in most solvents …”

“…[49][50][51][52][53][54][55][56] In addition, MWCNTs can be used as very good catalyst supports because of their high surface area and insolubility in most solvents. [57][58][59][60][61][62][63] In continuation of our recent investigations of the application of heterogeneous catalytic systems in cross-coupling reactions, [64][65][66][67] in the work reported here, palladium was immobilized on methyl histidinate-modified MWCNTs and the catalytic activity was demonstrated by employing the Mizoroki-Heck and Suzuki-Miyaura coupling reactions. Our catalytic system results in the desired products in faster reaction times, at lower temperatures using greener solvents in comparison with conventional methods.…”

A magnetic porous chitosan-based palladium catalyst: a green, highly efficient and reusable catalyst for Mizoroki–Heck reaction in aqueous media

“…7,8 However, phosphane ligands are sensitive to air oxidation, as well as being toxic, expensive, and unstable at high temperatures. Box 16315-1618, Tehran, Iran, Fax: +98-21-22853650; Tel: +98-21-23064323; E-mail: movassagh@kntu.ac.ir ionic liquids, 15 multi-walled carbon nanotubes [16][17][18] and polymers such as polystyrene, [19][20][21] polyethylene glycol, 22 polyvinyl chloride-polyethylene, 23 and polysaccharides. 9,10 Moreover, many catalysts used in the Heck reactions are homogeneous, which are impossible to be recovered and the residual palladium left in the product, confines the reaction; therefore, in recent years, the development of heterogeneous catalytic systems has increased.…”