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One-step continuous flow synthesis of highly substituted pyrrole-3-carboxylic acid derivatives via in situ hydrolysis of tert-butyl esters.

ABSTRACT: The first one-step, continuous flow synthesis of pyrrole-3-carboxylic acids directly from tert-butyl acetoacetates, amines, and 2-bromoketones is reported. The HBr generated as a byproduct in the Hantzsch reaction was utilized in the flow method to hydrolyze the t-butyl esters in situ to provide the corresponding acids in a single microreactor. The protocol was used in the multistep synthesis of pyrrole-3-carboxamides, including two CB1 inverse agonists, directly from commercially available starting materials in a single continuous process.

SUBMITTER: Herath A

PROVIDER: S-EPMC3005611 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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One-step continuous flow synthesis of highly substituted pyrrole-3-carboxylic acid derivatives via in situ hydrolysis of tert-butyl esters.

Herath Ananda A Cosford Nicholas D P ND

Organic letters 20101021 22

The first one-step, continuous flow synthesis of pyrrole-3-carboxylic acids directly from tert-butyl acetoacetates, amines, and 2-bromoketones is reported. The HBr generated as a byproduct in the Hantzsch reaction was utilized in the flow method to hydrolyze the t-butyl esters in situ to provide the corresponding acids in a single microreactor. The protocol was used in the multistep synthesis of pyrrole-3-carboxamides, including two CB1 inverse agonists, directly from commercially available star ...[more]

PMID: 20964284

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