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Published on: June 10, 2021
Redox cycloisomerization approach to 1,2-dihydropyridines
Barry M Trost1, Berenger Biannic1
1Department of Chemistry, Stanford University, Stanford, California 94305-5580, United States.
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.
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