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Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles.

ABSTRACT: An efficient construction of imidazole ring by a Cs2CO3-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Internal alkynes can also undergo the annulation to give 2,4,5-trisubstituted imidazoles.

SUBMITTER: Mehmood H

PROVIDER: S-EPMC7463794 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles.

Mehmood Hina H Iqbal Muhammad Asif MA Lu Le L Hua Ruimao R

Molecules (Basel, Switzerland) 20200809 16

An efficient construction of imidazole ring by a Cs2CO3-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Internal alkynes can also undergo the annulation to give 2,4,5-trisubstituted imidazoles. ...[more]

PMID: 32784900

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