Highly porous chitosan microspheres supported palladium catalyst for coupling reactions in organic and aqueous solutions

Microstructure-stability relations studies of porous chitosan microspheres supported palladium catalysts

“…The cross-coupling product ((E)-butyl cinnamate) was characterized by its spectroscopic data ( 1 H NMR and GC/MS) and melting point. The characterization result was consistent with the literatures [27,29].…”

“…In the recent work [27], the resultant Pd/PCMS (from CS/PEG20000 semi-IPN porous chitosan microsphere supported palladium) has been demonstrated as a highly active catalyst with high functional group tolerance of the starting materials for the Ullmann-type reductive homocoupling of aromatic halides and the Heck cross-coupling of aromatic halides with acrylates. It has been demonstrated that the polar solvents such as dimethyl sulfoxide (DMSO) [28], dimethylformamide (DMF) and alcohols can be used as the reducing reagents to regenerate the reductive Pd 0 active species from the oxidative Pd 2+ species to complete the catalytic redox cycle [33,34].…”

“…We [24][25][26] have reported the preparation of the highly porous chitosan membranes through the selective dissolution of the water-soluble polymers from the chitosan semi-IPN membranes. Recently, we [27] have extended this convenient technology for the preparation of the porous chitosan microspheres (PCMS) from the crosslinking chitosan/polyethylene glycol (PEG20000) interpenetrating microspheres through the selective dissolution of the water-soluble PEG component for the immobilization of palladium catalysts. The PCMS supported palladium catalysts (Pd/PCMS) have been demonstrated as highly active and easily recyclable heterogeneous catalysts.…”

Porous membrane based on chitosan–SiO2 for coin cell proton battery

“…Several studies have also focused on the production of porous chitosan membranes using porogen agents [10][11][12]. The removal of porogen agents, such as silica (SiO 2 ), from the polymeric membrane could create $ 20-32 μm pores [13][14][15].…”

Porous Chitosan Microspheres Supported-palladium Catalyst for the C–N Cross-coupling of Aryl Halides with Secondary Amines

“…Recently, we reported that porous chitosan microspheres-supported palladium heterogeneous catalysts have been evaluated using the Ullmann reductive homocoupling and the Heck cross-coupling reactions. 14,15 Further study, however, was needed of the activities, stabilities and recyclability of the porous chitosan microspheres-supported palladium catalysts. Here we present an efficient synthesis for a variety of arylamines by supportedpalladium-catalysed cross-coupling amination of aryl halides without the need for inert-gas protection.…”