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Regioselective alkane oxygenation with H<sub>2</sub>O<sub>2</sub> catalyzed by titanosilicalite TS-1
Auteur(s)
Shul’pin, Georgiy B.
Sooknoi, Tawan
Romakh, Vladimir B.
Shul’pina, Lidia S.
Date de parution
2006
In
Tetrahedron Letters, Elsevier, 2006/47/18/3071-3075
Résumé
Titanosilicalite TS-1 catalyses oxidation of light (methane, ethane, propane and n-butane) and normal higher (hexane, heptane, octane and nonane) alkanes to give the corresponding isomeric alcohols and ketones. The oxidation of higher alkanes proceeds in many cases with a unique regioselectivity. Thus, in the reaction with <i>n</i>-heptane the CH<sub>2</sub> groups in position 3 exhibited a reactivity 2.5 times higher than those of the other methylene groups. This selectivity can be enhanced if hexan-3-ol is added to the reaction mixture, the 3-CH<sub>2</sub>/2-CH<sub>2</sub> ratio becoming 10. It is assumed that the unusual selectivity in the oxidation of <i>n</i>-heptane (and other higher alkanes) is due to steric hindrance in the catalyst cavity. As a result, the catalytically active species situated on the catalyst walls can only easily react with certain methylenes of the alkane, which is adsorbed in the cavity taking U-shape (hairpin) conformations.
Identifiants
Type de publication
journal article
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