| 摘 要： | 1 Results Classic oxidants require rigorous control of the experimental conditions added with the problem of lack of selectivity. Catalysis by transition metals with environmentally safe oxidants provides synthetic routes to minimize pollution by giving environmental benign by-products. Fe (Ⅵ) is a powerful and a selective oxidant with Fe(Ⅲ) as a by-product, while hydrogen peroxide is clean with water as the only by-product. Separation of sodium or potassium ferrates requires tedious processes. Association of a ferric salt with a clay support had been reported previously also1-2],which prompted us to find out a way in which sodium ferrate could be used in solution itself. Presence of copper nano-particles adsorbed on solid support, accelerate the process. Present study3] describes the oxidation of organic substrates with in-situ prepared Fe(Ⅵ)in combination of montmorillonite K10 and metallic copper nano-particles without following the tedious and lengthy process of separation of Fe(Ⅵ). Apart from it the catalytic activities of three transition metals palladium(Ⅱ), iridium(Ⅲ) and rhodium(Ⅲ) in solution phase and under solvent less conditions were studied in the oxidation of various organic compounds by hydrogen peroxide4] and cerium(Ⅳ) sulphate. In the oxidation by hydrogen peroxide (with substrate: catalyst ratio 1∶62 500 to 1∶1 961) palladium(Ⅱ) was found to be the most efficient catalyst, while iridium(Ⅲ) (catalyst: substrate ratio 1∶57 to 151) was so much efficient with cerium(Ⅳ) that it oxidizes even cyclohexane and benzene giving rise to 44% and 51.8% yields of carbonyl compounds.
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