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Sterically Demanding Oxidative Amidation of ?-Substituted Malononitriles with Amines Using O2.

ABSTRACT: An efficient amidation method between readily available 1,1-dicyanoalkanes and either chiral or nonchiral amines was realized simply with molecular oxygen and a carbonate base. This oxidative protocol can be applied to both sterically and electronically challenging substrates in a highly chemoselective, practical, and rapid manner. The use of cyclopropyl and thioether substrates support the radical formation of ?-peroxy malononitrile species, which can cyclize to dioxiranes that can monooxygenate malononitrile ?-carbanions to afford activated acyl cyanides capable of reacting with amine nucleophiles.

SUBMITTER: Li J

PROVIDER: S-EPMC5094546 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Sterically Demanding Oxidative Amidation of α-Substituted Malononitriles with Amines Using O2.

Li Jing J Lear Martin J MJ Hayashi Yujiro Y

Angewandte Chemie (International ed. in English) 20160614 31

An efficient amidation method between readily available 1,1-dicyanoalkanes and either chiral or nonchiral amines was realized simply with molecular oxygen and a carbonate base. This oxidative protocol can be applied to both sterically and electronically challenging substrates in a highly chemoselective, practical, and rapid manner. The use of cyclopropyl and thioether substrates support the radical formation of α-peroxy malononitrile species, which can cyclize to dioxiranes that can monooxygenat ...[more]

PMID: 27300467

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