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Autoxidation of Heterocyclic Aminals.

ABSTRACT: The autoxidation reactions of 2-acyl-2,3-dihydroquinazolin-4(1H)-ones 4a and 5a and 2,2'-bis(dihydroquinazolinone) 6a are described. These reactions generate aminyl radicals that undergo ?-C-C cleavage, and subsequent reactions of the resulting C-based radicals with O₂ lead to diverse products with good selectivity, depending on the structure of the substrate. Oxidation of 4a, in which the 2-acyl group is part of a cyclic acenaphthenone unit, yields a heterocyclic C-hydroperoxylaminal via 1,2-acyl migration. Oxidation of 5a, which contains a 2-acetyl group, yields peracetic acid and a quinazolinone product. Oxidation of 6a forms a bis(quinazolinone) by net dehydrogenation.

SUBMITTER: Zhai F

PROVIDER: S-EPMC6641016 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Autoxidation of Heterocyclic Aminals.

Zhai Feng F Jordan Richard F RF

ACS omega 20170629 6

The autoxidation reactions of 2-acyl-2,3-dihydroquinazolin-4(1H)-ones 4a and 5a and 2,2'-bis(dihydroquinazolinone) 6a are described. These reactions generate aminyl radicals that undergo β-C-C cleavage, and subsequent reactions of the resulting C-based radicals with O2 lead to diverse products with good selectivity, depending on the structure of the substrate. Oxidation of 4a, in which the 2-acyl group is part of a cyclic acenaphthenone unit, yields ...[more]

PMID: 31457639

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