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Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen.

ABSTRACT: The methylene group of various substituted 2- and 4-benzylpyridines, benzyldiazines and benzyl(iso)quinolines was successfully oxidized to the corresponding benzylic ketones using a copper or iron catalyst and molecular oxygen as the stoichiometric oxidant. Application of the protocol in API synthesis is exemplified by the alternative synthesis of a precursor to the antimalarial drug Mefloquine. The oxidation method can also be used to prepare metabolites of APIs which is illustrated for the natural product papaverine. ICP-MS analysis of the purified reaction products revealed that the base metal impurity was well below the regulatory limit.

SUBMITTER: Sterckx H

PROVIDER: S-EPMC4734388 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen.

Sterckx Hans H De Houwer Johan J Mensch Carl C Herrebout Wouter W Tehrani Kourosch Abbaspour KA Maes Bert U W BU

Beilstein journal of organic chemistry 20160127

The methylene group of various substituted 2- and 4-benzylpyridines, benzyldiazines and benzyl(iso)quinolines was successfully oxidized to the corresponding benzylic ketones using a copper or iron catalyst and molecular oxygen as the stoichiometric oxidant. Application of the protocol in API synthesis is exemplified by the alternative synthesis of a precursor to the antimalarial drug Mefloquine. The oxidation method can also be used to prepare metabolites of APIs which is illustrated for the nat ...[more]

PMID: 26877817

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