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Regioselective Base-Mediated Cyclizations of Mono-N-acylpropargylguanidines.

ABSTRACT: A regioselective base-mediated cyclization of mono-N-acylpropargylguanidines is reported. A related Ag(I)-catalyzed hydroamination strategy was recently employed to yield N3-Cbz-protected ene-guanidines, which found utility in the synthesis of naamidine A. Herein, we report the base-catalyzed hydroamination of mono-N-acylpropargylguanidines, which proceeds with the opposite regiochemistry to deliver isomerized N2-acyl-2-aminoimidazoles with broad substrate scope, circumventing the problematic regiospecific acylation of free 2-aminoimidazoles.

SUBMITTER: Salvant JM

PROVIDER: S-EPMC6016371 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Regioselective Base-Mediated Cyclizations of Mono-N-acylpropargylguanidines.

Salvant Justin M JM Edwards Anne V AV Kurek Daniel Z DZ Looper Ryan E RE

The Journal of organic chemistry 20170615 13

A regioselective base-mediated cyclization of mono-N-acylpropargylguanidines is reported. A related Ag(I)-catalyzed hydroamination strategy was recently employed to yield N<sup>3</sup>-Cbz-protected ene-guanidines, which found utility in the synthesis of naamidine A. Herein, we report the base-catalyzed hydroamination of mono-N-acylpropargylguanidines, which proceeds with the opposite regiochemistry to deliver isomerized N<sup>2</sup>-acyl-2-aminoimidazoles with broad substrate scope, circumvent ...[more]

PMID: 28558466

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