We report a selective dearomative cyclization strategy for the synthesis of 3,4-fused diazabicycles from 3-substituted pyridyl ynamides. The method combines a chemo-, regio-, and stereoselective carbometalation with a regioselective dearomatization, enabling access to a broad range of diazabicyclic scaffolds with varied ring sizes. The protocol accommodates alkyl and aryl Grignard reagents, tolerates diverse functional groups, and supports stereodivergent synthesis, offering a versatile platform for constructing complex fused N-heterocycles with potential relevance to medicinal chemistry.

We report a site- and regioselective Heck-type arylation reaction for the synthesis of highly 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