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One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor.

ABSTRACT: The Bohlmann-Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. In the Bohlmann-Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates to give the corresponding trisubstituted pyridine as a single regioisomer in good yield. Furthermore, 3-substituted propargyl aldehydes undergo Hantzsch dihydropyridine synthesis in preference to Bohlmann-Rahtz reaction in a very high yielding process that is readily transferred to continuous flow processing.

SUBMITTER: Bagley MC

PROVIDER: S-EPMC3817555 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor.

Bagley Mark C MC Fusillo Vincenzo V Jenkins Robert L RL Lubinu M Caterina MC Mason Christopher C

Beilstein journal of organic chemistry 20130930

The Bohlmann-Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. In the Bohlmann-Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates to give the corresponding trisubstituted pyridine as a single regioisomer in good yield. Furthermore, ...[more]

PMID: 24204407

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