| Abstract
| - A versatile and simple method for aerobic oxidation of various aromatics containing an oxygen-functionalized benzylic carbon is reported. Results from oxidation experiments with methyl arylketones, benzaldehydes, benzylic alcohols, and mandelic acid are reported; all provide high yieldsof the corresponding aromatic carboxylic acids. By means of response surface methodology andmechanistic interpretation it is revealed that the oxidation process operates catalytically usingelectron-deficient nitroarenes, such as 1,3-dinitrobenzene, 1,2,3-trifluoro-4-nitrobenzene, and 2,4-difluoro-1-nitrobenzene, with molecular oxygen as the terminal oxidant. The reaction is carriedout in a basic solution of potassium tert-butoxide in tert-butyl alcohol. Since the terminal oxidantis molecular oxygen and only 5−10 mol % of, e.g., 1,3-dinitrobenzene as catalyst is used, the newmethod represents an environmentally benign alternative to, for example, the well-known haloformreaction. The method is also a convincing alternative when transition metal free conditions arerequired.
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