Efficient liquid phase oxidation of olefins and aromatic alcohol catalyzed by reusable polymer anchored Schiff base complexes

Abstract

BACKGROUND: Heterogenization of homogeneous catalyst has become an interesting process for the catalytic oxidation of olefins and aromatic alcohol. This may provide a new kind of catalyst that is not only friendly to the environment but also exhibits higher thermal and chemical stabilities.

Polymer Anchored Catalysts for Oxidation of Styrene Using TBHP and Molecular Oxygen

“…Heterogenized transition metal complexes, especially those with Schiff base on polymer support, were found to be efficient catalysts for the oxidation of various olefins and alcohols using different oxidants. 22,23 Gupta et al 24 reviewed polymer supported Schiff base complexes as catalysts for various alkenes and reported that Mn(III), Ru(III), Cu(II), Fe(III), Co(II), and Ni(II) were active metals for oxidation reactions. Chang et al 25 reported the cyclohexene oxidation using O 2 as oxidant catalyzed by chloromethylated polystyrene supported tridendate Schiff base Cu(II), Ni(II), Co(II), and Mn(II) complexes; Cu(II) complex was found to be most active (51.9% conversion).…”

“…Polymer anchored metal complexes are gaining importance as efficient heterogeneous catalysts in a variety of organic transformations including oxidation and hydrogenation reactions because they are insoluble, recyclable, and generate less solid waste than nonsupported catalysts, which make the overall process more environmental friendly. , Sherrington et al synthesized various polymeric supports by the immobilization of Mo­(VI) metal and tested for epoxidation of alkene in presence of tert -butylhydroperoxide. Heterogenized transition metal complexes, especially those with Schiff base on polymer support, were found to be efficient catalysts for the oxidation of various olefins and alcohols using different oxidants. , Gupta et al reviewed polymer supported Schiff base complexes as catalysts for various alkenes and reported that Mn­(III), Ru­(III), Cu­(II), Fe­(III), Co­(II), and Ni­(II) were active metals for oxidation reactions. Chang et al reported the cyclohexene oxidation using O 2 as oxidant catalyzed by chloromethylated polystyrene supported tridendate Schiff base Cu­(II), Ni­(II), Co­(II), and Mn­(II) complexes; Cu­(II) complex was found to be most active (51.9% conversion).…”

Polymer supported Pd catalyzed carbonylation of aryl bromides for the synthesis of aryl esters and amides

“…The stretching vibration of C]N bond appeared at 1698 cm À1 for the polymer-bound Schiff base ligand which is shied to 1690 cm À1 in the metal complex. 40,41 Characteristic peak of free OH appeared at 3377 cm À1 for the ligand and its intensity is reduced in the complex. 42 A peak is observed at 1246 cm À1 (v C-O, phenolic) in the ligand and at 1243 cm À1 in the complex.…”

Oxidative cleavage of alkynes: a review of the methods invented so far and their application possibilities in green organic synthesis

“…160 Although Shaikh et al investigated the reaction mechanism for the oxidative cleavage of olefins with GC-MS, however, there was no specific reaction-mechanistic investigation for the alkynes (see supporting information) 160 . The reaction mechanism of Fe-catalyzed oxidative cleavage of olefins has also been studied by Islam et al 161 Enthaler et al have studied the Fe-catalyzed oxidative cleavage in more detail. They have tested a range of iron salts with different ligands and additives in hydrogen peroxide as an oxidant.…”