乙酸酐和DMSO作为活化剂的将醇氧化为醛酮的反应。Albright, J. D.和Goldman, L. 在1965年首先系统的介绍了此反应。【J. Am. Chem. Soc. 1965, 87, 4214】。反应也可在在室温下进行,延长反应时间至12-24小时。此方法不是很好的氧化醇为醛酮的方法,基本可以用Swern氧化反应代替,该反应特别对立体位阻较大的醇的氧化效果较好。
用Ac2O做活性化剂,可避免难于后处理的缺点,也不需要加给质子体,此法用于位阻大的醇的氧化可获满意结果,缺点是对于位阻小的羟基,可发生乙酰化及生成甲硫甲醚(Pummerer反应)的副反应。
Generalprocedure for oxidation of alcohols by Albright–Goldman methodAmixture of ca. 20–60 equiv. of acetic anhydride in 0.05–0.4 M solution of 1equiv. of alcohol in dry DMSO is stirred at r.t. under a blanket of an inertgas, till most of the starting compound is consumed. Hindered alcohol mayrequire heating at 60-100C. The work-up can be made according to twoalternative protocols:Afterthe oxidation, the crude aldehyde or ketone can be secured by simpleconcentration in vacuo that can be subjected to a further work-up according tomethod B.Thereaction mixture is mixed with water or ice. This may result in theprecipitation of the product that can be separated by filtration. If noprecipitation occurs, the product can be extracted with an organic solvent,such as CH2Cl2, CHCl3, Et2O orEtOAc. The organic phase is washed with an aqueous solution of sodiumbicarbonate, in order to eliminate acetic acid residues. It can be additionallywashed with plain water and/or brine. Finally, the organic phase is dried (Na2SO4or MgSO4), and concentrated to give a crude product that may needfurther purification.1.common oxidation reagents, Yue Xu,Sundia Meditech2. Strategic Applications of Named Reactions in Organic Synthesis, László Kürti andBarbara Czakó, Pfitzner-Moffatt oxidation,page 3463. http://www.chem-station.com/cn/?p=1243
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