title: Effective and mild method for converting 3β-hydroxysteroids to 3-keto steroids via DDQ/TEMPO.
abstract: A mild and efficient oxidation of 3β-hydroxysteroids to the corresponding 3-keto steroids can be carried out at room temperature, using DDQ in the presence of catalytic TEMPO. Oxidation of saturated 3β-hydroxysteroids gave the corresponding ketones in excellent yield. The 5-unsaturated 3β-hydroxysteroids are oxidized selectively to 4-en-3-one or 4,6-diene-3-one derivatives according to the amount of DDQ in reaction. This is a good method for the synthesis of 4,6-diene-3-one from the corresponding 3β-hydroxy-5-ene steroids. Meanwhile, configurations of the oxidation compounds 2a, 2b, 3b, 2c, 2f and 2g were identified by X-ray diffraction. A possible mechanism is presented and discussed.
authors.affiliation: College of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Key Laboratory of Development and Application of Forest Chemicals of Guangxi, Nanning 530006, China.
authors.forename: Wu
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Key Laboratory of Development and Application of Forest Chemicals of Guangxi, Nanning 530006, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Pan
authors.affiliation: College of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Key Laboratory of Development and Application of Forest Chemicals of Guangxi, Nanning 530006, China.
authors.forename: Aiqun
authors.initials: A
authors.lastname: Wu
authors.affiliation: College of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Key Laboratory of Development and Application of Forest Chemicals of Guangxi, Nanning 530006, China. Electronic address: liqunshen@126.com.
authors.forename: Liqun
authors.initials: L
authors.lastname: Shen
mesh_terms: D016227:Benzoquinones / Q000737:chemistry*; D003497:Cyclic N-Oxides / Q000737:chemistry*; D006914:Hydroxysteroids / Q000737:chemistry*; D013696:Temperature
chemical_list: D016227:Benzoquinones; D003497:Cyclic N-Oxides; D006914:Hydroxysteroids; C000928:dichlorodicyanobenzoquinone; C003959:TEMPO
keywords: 3-Keto steroids; 3β-Hydroxysteroids; DDQ; Oxidation; TEMPO