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Redox cycloisomerization approach to 1,2-dihydropyridines.

ABSTRACT: The phosphine-catalyzed synthesis of 1,2-dihydropyridines via an alkyne isomerization/electrocyclization sequence is described. Propargylidenecarbamate substrates were prepared following a one-pot procedure between a terminal alkyne, a benzonitrile, and a chloroformate in the presence of trimethylaluminum. This methodology gives access to a diverse set of 2,6-disubstituted 1,2-dihydropyridines in high yield. The products can be easily converted into substituted piperidines or pyridines, and this methodology was applied to the synthesis of indolizidines.

SUBMITTER: Trost BM

PROVIDER: S-EPMC4883060 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Redox cycloisomerization approach to 1,2-dihydropyridines.

Trost Barry M BM Biannic Berenger B

Organic letters 20150311 6

The phosphine-catalyzed synthesis of 1,2-dihydropyridines via an alkyne isomerization/electrocyclization sequence is described. Propargylidenecarbamate substrates were prepared following a one-pot procedure between a terminal alkyne, a benzonitrile, and a chloroformate in the presence of trimethylaluminum. This methodology gives access to a diverse set of 2,6-disubstituted 1,2-dihydropyridines in high yield. The products can be easily converted into substituted piperidines or pyridines, and this ...[more]

PMID: 25760318

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