Procedure for the aerobic oxidation of a sulfoxide group to a sulfone.
The present invention relates to a procedure for the oxidation of a sulfoxide group to a sulfone group. The procedure consists in the oxidation of the sulfoxide with air in the presence of a molibdenum compound as catalyst, preferentially dioxomolibdenum (VI) bis(acetilacetonate) or dinuclear derivatives coming from its partial hydrolisis.
The main novelty of the present method is the use of air as oxidating agent, while clasical procedures make use of hydrogen peroxide, risky to store and handle due to its corrosive nature and explosive vapors.
The present invention relates to a procedure for the oxidation of sulfoxides to sulfones using the oxygen from the air as oxidizing agent, in the presence of a molibdenum complex as catalyst, preferably dioxomolibdenum (VI) bis(acetilacetonate) or dinuclear derivatives coming from its partial hydrolisis in the presence of dimethylsulfoxide, dimethylformamide or triphenylphosphine oxide. The amount of catalyst varies from 1 mol% to 10 mol%. The synthesis is performed at atmospheric pressure and the temperature varies from 15-50 ºC. The solvent used is a low molecular weight ether. The products are obtained in excellent yields and byproducts are not observed in the reaction.
This new procedure is more efficient than other procedures described for the process. Moreover, air stands out for being the cheapest, most available, easiest to handle and safest oxidizing agent. Additionally, molibdenum catalysts are less toxic that commonly used ones, and are resistant to degradation under reaction conditions. Finally, byproduct formation is not observed and sulfones are easily isolable.
Overall, the procedure is efficient, simple, cheap, and enviromentally friendlier than previous methods.
Synthesis of sulfones, that can show diverse already demonstrated propierties (drugs, pesticides, materials,...). Therefore, applications in pharmaceutical and agrochemical industries.
Número de solicitud: P200703331
Fecha de solicitud: 14/12/2007
Número de patente: ES2326110B1
Fecha de concesión: 13/06/2010
NEW METHODS IN ORGANIC SYNTHESIS
Isabel Pinto Pascual
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