Nickel-Catalyzed Stereospecific Alkylation of Vinylsiloxanes Using Pyridinium Salts

A methodology for radical cross-coupling with vinylsiloxanes and pyridinium salts under nickel catalysis is described. Easily implemented from inexpensive and abundant primary amines and terminal alkynes, this Hiyama coupling provides efficient access to (<i>E</i>), (<i>Z</i>), and (<i>1,1'</i>)-alkenes with selectivity control. Operating under mild conditions, this robust strategy applies to a broad range of functional groups with diverse double bond stereochemistries. This versatile reaction is scalable and straightforward, accommodating both secondary and primary alkyl groups.