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Synthesis of Various 2-Aminobenzoxazoles: The Study of Cyclization and Smiles Rearrangement.

ABSTRACT: This study reports two synthetic approaches leading to 2-aminobenzoxazoles and their N-substituted analogues. Our first synthetic strategy involves a reaction between various o-aminophenols and N-cyano-N-phenyl-p-toluenesulfonamide as a nonhazardous electrophilic cyanating agent in the presence of Lewis acid. The second synthetic approach uses the Smiles rearrangement upon activation of benzoxazole-2-thiol with chloroacetyl chloride. Both developed synthetic protocols are widely applicable, afford the desired aminobenzoxazoles in good to excellent yields, and use nontoxic and inexpensive starting material.

SUBMITTER: Slachtova V

PROVIDER: S-EPMC6868899 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Synthesis of Various 2-Aminobenzoxazoles: The Study of Cyclization and Smiles Rearrangement.

Šlachtová Veronika V Chasák Jan J Brulíková Lucie L

ACS omega 20191105 21

This study reports two synthetic approaches leading to 2-aminobenzoxazoles and their N-substituted analogues. Our first synthetic strategy involves a reaction between various o-aminophenols and N-cyano-N-phenyl-p-toluenesulfonamide as a nonhazardous electrophilic cyanating agent in the presence of Lewis acid. The second synthetic approach uses the Smiles rearrangement upon activation of benzoxazole-2-thiol with chloroacetyl chloride. Both developed synthetic pr ...[more]

PMID: 31763555

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