Insights into the Heck-Type Arylation of 1,2-Dihydropyridines: Site- and Regioselective Access to 2,3-Disubstituted Dihydropyridines

Abstract

We report a site- and regioselective Heck-type arylation reaction for the synthesis of substituted 1,2-dihydropyridines from simple pyridine precursors. This transformation serves as a key step in our previously developed stepwise dearomative multi-functionalization platform, enabling the syn-addition of aryl halides to dihydropyridine intermediates under mild conditions. Comprehensive scope studies demonstrate broad functional group tolerance, accommodating both electron-rich and electron-deficient aryl iodides, a variety of N-protecting groups, and diverse C2 substituents.

Keywords

Dearomative functionalization - Carbopalladation - Heterocycles - Site-selectivity - Regioselectivity - Functional molecules

Publication History

Received: 24 April 2025

Accepted after revision: 30 May 2025

Accepted Manuscript online:
30 May 2025

Article published online:
23 July 2025

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