Oxidation of Methylpyridines and Methylquinolines

Pyridinecarboxylic adds are useful and important intermediates in pharmaceutical syntheses. Although the synthesis of these carboxylic adds by the aerobic oxidation of alkylpyridines is straightforward, the oxidation is usually difficult to carry out selectively owing to their low reactivities [52,56). Pyridinecarboxylic acids are readily prepared by the oxidation of alkylpyridines with nitric add or by the hydrolysis of pyridinecarboxamides derived from pyridinecarbonitrile [57]. According to the 

Treatment of 3-methylquinoline (10) by the NHPI-Co-Mn system under the readion condition used for P-picoline, however, results in the recovery of the starting 10. This is believed to be because the activation of O2 by the Co(II) becomes difficult, probably because of coordination of 10 to Co(OAc)2. As described below, the nitration of alkanes with NO2 is enhanced in the presence of NHPI catalyst, in which 

Hydroperoxides are used not only as oxidizing agents of alkenes but also as important precursors for the synthesis of phenols. For instance, a-hydroperoxyethyl-benzene, obtained by aerobic oxidation of ethylbenzene, is used as an active oxygen 

A one-pot synthesis of phenol and cydohexane from cydohexylbenzene was later achieved by using NHPI catalyst followed by treatment with sulfuric acid, which 

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