Polymer supported Cu(II) catalyst was prepared, characterized and employed for the N-arylation and amination reaction of N-H heterocycles with aryl halides as well as arylboronic acids to afford the corresponding coupled products in good to excellent yields. This catalyst can be used several times with consistent catalytic activity.

A new polymer-supported Cu(II) Schiff base complex has been synthesized and characterized by elemental (including metal) analysis, FT-IR spectroscopy, UV-Vis diffuse reflectance spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The catalytic performance of this complex was evaluated in the epoxidation of styrene in acetonitrile/N,N-dimethylformamide (9:1) mixture with 70% tert-butyl hydroperoxide as an oxidizing agent under liquid phase reaction conditions for selective synthesis of styrene oxide. Suitable reaction conditions have been optimized by considering the effects of various reaction parameters such as temperature, reaction time, solvent, oxidant, catalyst amount, and styrene to hydroperoxide molar ratio for the maximum conversion of styrene as well as selectivity of styrene oxide. We have also investigated the epoxidation reaction of various olefins under the optimized reaction conditions. Comparison between catalytic activities of the polymer-supported Cu(II) Schiff base complex and its homogeneous analogue showed that the polymer-supported catalyst was more active. This heterogeneous complex was reused for five times. The selectivity of the heterogeneous catalyst does not change even after five times of reusing.

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Immobilization of copper onto polystyrene provided a polymer-supported copper(II) catalyst, which was effective in cross-coupling reactions between N-containing substrates and arylboronic acids using methanol as a solvent in air under base-free conditions. This catalyst was also effective in N-arylation of imidazole with aryl halides in DMSO using K 2 CO 3 as a base under nitrogen atmosphere. The catalyst was characterized by physicochemical and spectroscopic techniques. The product N-arylimidazoles and N-arylbenzimidazoles were isolated in good to excellent yields. This copper catalyst was air stable and could be recycled with minimal loss of activity.

A tetradentate Schiff base (teta), obtained from triethylenetetramine and salicylaldehyde, has been covalently bonded to divinylbenzene cross-linked chloromethylated polystyrene. This chelating ligand, abbreviated as PS-teta (PS = polymeric support), reacts with metal chlorides (Cu 2? , Co 2? , and Ni 2? ) in methanol to give polymerbound transition metal complexes, PS-Cu(II)teta/(Cat-1), PS-Ni(II)teta/(Cat-2), and PS-Co(II)teta/(Cat-3), formation of which has been established by various physiochemical methods and spectroscopic techniques. The catalytic potential of these materials has been tested for the oxidation of various alkenes, alkanes, alcohols, and thioethers in the presence of 30% H 2 O 2 as an oxidant. At the same time, these catalysts are very stable and could be reused in oxidation reactions for more than five times without noticeable loss of their catalytic activity.