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Synthesis of Novel Heterocycles by Amide Activation and Umpolung Cyclization.

ABSTRACT: Herein, we report a metal-free synthesis of cyclic amidines, oxazines, and an oxazinone under mild conditions by electrophilic amide activation. This strategy features an unusual Umpolung cyclization mode and enables the smooth union of α-aryl amides and diverse alkylazides, effectively rerouting our previously reported α-amination transform.

SUBMITTER: Zhang H

PROVIDER: S-EPMC7091535 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Synthesis of Novel Heterocycles by Amide Activation and Umpolung Cyclization.

Zhang Haoqi H Riomet Margaux M Roller Alexander A Maulide Nuno N

Organic letters 20200311 6

Herein, we report a metal-free synthesis of cyclic amidines, oxazines, and an oxazinone under mild conditions by electrophilic amide activation. This strategy features an unusual Umpolung cyclization mode and enables the smooth union of α-aryl amides and diverse alkylazides, effectively rerouting our previously reported α-amination transform. ...[more]

PMID: 32159354

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