@article { ISI:000319458900005, title = {Modified zeolite immobilized palladium for ligand-free suzuki-miyaura cross-coupling reaction}, journal = {Journal of Organometallic Chemistry}, volume = {738}, year = {2013}, month = {AUG}, pages = {29-34}, publisher = {ELSEVIER SCIENCE SA}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

A palladium-based catalyst supported on modified ZSM-5 was successfully prepared by a facile procedure. The prepared heterogeneous catalyst Pd@desilicated ZSM-5 showed an excellent catalytic activity at very low Pd loading (0.02 mol\%) for the ligand-free Suzuki-Miyaura coupling reactions of various aryl bromides affording excellent yields of the products. The prepared catalyst presents good recyclability, over four catalytic cycles. (C) 2013 Elsevier B. V. All rights reserved.

}, keywords = {heterogeneous catalysis, Suzuki-Miyaura reaction, zeolite}, issn = {0022-328X}, doi = {10.1016/j.jorganchem.2013.03.031}, author = {Kumbhar, Arjun and Kamble, Santosh and Mane, Anand and Jha, Ratnesh Kumar and Salunkhe, Rajashri} } @article {48908, title = {CuNPs@Al2O3-cellulose composite for the ligand-free Suzuki cross-coupling reactions in batch and continuous flow process}, journal = {Journal of Organometallic Chemistry }, volume = {1004}, year = {2024}, month = {JAN}, type = {Article}, abstract = {

In the present work, we synthesized recyclable CuNPs@Al2O3-CELL composite from an inexpensive and commercially available synthetic reagent by a simple method. The catalyst was characterized by various techniques such as TGA (Thermogravimetric analysis), SEM (Scanning electron microscope), TEM (Transmission electron microscopy), XPS (X-ray photoelectron spectroscopy), EDS (Energy dispersive spectroscopy), and AAS (Atomic Absorption Spectroscopy). The composite was applied for the Suzuki coupling reactions in the batch and flow process. The aryl halides were easily coupled with arylboronic acids in 95 \% ethanol at 78 C. We systematically investigated the role of reaction temperature, solvent, and catalyst loading, on the transient and steady-state behavior of the flow reactor through an automated flow chemistry platform. The CuNPs@Al2O3CELL catalytic particles demonstrate minimal deactivation and leaching over a continuous Suzuki coupling reaction at a 20 min nominal residence time at 100 C. Moreover, the catalyst can be recovered by simple filtration and reused at least five times with a moderate decrease in product yield. The excellent activity and stability of the catalyst have been attributed to the strong chelation of the Cu species with hydroxyl functional groups of the Al2O3-CELL composite. The catalytic system was highly efficient in Suzuki coupling of various aryl bromides with different aryl boronic acids, yielding good to excellent product yields (80-96 \%) with a TON of 15.914-19.066 and TOF of 2.649-9.533 h(-1).

}, keywords = {Continuous flow process, CuNPs@Al2O3-CELL, ligand-free, recyclable, Suzuki coupling}, issn = {0022-328X}, doi = {10.1016/j.jorganchem.2023.122954}, author = {Patil, Seema and Rajmane, Archana and Jadhav, Sanjay and Rode, Chandrashekhar and Kumbhar, Arjun} } @article {49578, title = {Br{\o}nsted basic TMMM-hydrotrope combined catalytic system for the synthesis of diverse dihydropyranochromenes in water at ambient temperature}, journal = {New Journal of Chemistry}, volume = {49}, year = {2025}, month = {MAY}, pages = {8131-8142}, type = {Article}, abstract = {

This work describes the synthesis of a range of bioactive chromenes using a solid Br \& oslash;nsted organic base called {\textquoteleft}tris(morpholinomethyl)mesitylene{\textquoteright} (TMMM). TMMM was obtained in high yields by treating tris(bromomethyl)mesitylene (TBMM) with morpholine in the presence of K2CO3 in acetonitrile at RT. It was characterized using 1H NMR and 13C NMR spectroscopy. We developed a Br \& oslash;nsted base hydrotrope combined catalytic system (BBHC) by combining TMMM and a hydrotrope (sodium p-toluene sulphonate: NaPTS) for the cascade-type Knoevenagel-Michael addition reactions of various aldehydes and malononitrile with kojic acid, 4-hydroxy coumarin, dimedone, and lawsone in water. The methodology offers diversity-oriented synthesis (DOS) of dihydropyranochromenes in high yields. The BBHC catalytic system showed at least four times recyclability without appreciable loss of its activity. TMMM is an odorless, solid organic base that can be easily handled and is resistant to air and moisture. As TMMM is a solid base, it can reduce evaporation losses, improve safety and allow its easy recovery and reuse. TMMM acts as a powerful Br \& oslash;nsted base that activates reactants, while an aqueous solution of NaPTS acts as a hydrotrope that increases the solubility of organic compounds in water.

}, issn = {1144-0546}, doi = {10.1039/d5nj00663e}, author = {Rajmane, Archana and Jadhav, Aishwarya and Patil, Nita and Kumbhar, Arjun} }