| 摘要 |
A process for oxidizing organic substrates such as ketones and ethylenically unsaturated compounds. The substrate is contacted with aqueous hydrogen peroxide in a solution or in a two-phase liquid system, in the presence of a polymeric catalyst containing chemically bonded arsenic. This process can lead to lactones or hydroxy acids from cyclic ketones or to esters or mixtures of alcohol and carboxylic acid from open chain ketones. Unsaturated compounds afford epoxides and/or diols. Preparations of certain polymers substituted by arsenic groups, particularly from polystyrene, poly(vinylpyridine) and copolymers thereof, useful as catalysts in such oxidation process, are described. For example, polystyrene is brominated, bromine therein is replaced by lithium and the resulting lithiated polymer is converted into a polymer containing an arsenic group, such as arsono, -As(O)(OH)2, as substituent group, by reaction with arsine triethoxide followed by oxidation and hydrolysis by aqueous hydrogen peroxide. The aromatic polymers, polyphenylene and polymers and copolymers of vinylpyridine, can be used similarly as the catalyst.
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