Palladium-Catalyzed C-H Alkynylation of Unactivated Alkenes.

Palladium-catalyzed regio- and diastereoselective C-H functionalization with bromoalkynes and electronically unbiased olefins is reported. The picolinamide directing group enables the formation of putative 5 and 6-exo-metallacycles as intermediates to afford monoalkynylated products in up to 91 % yield in a stereospecific fashion. The systematic study reveals that substrates with a wide range of substituents on the olefin and bromoalkyne coupling partners are tolerated. Chemoselective transformations were demonstrated for the obtained amides, olefins, and alkynes.