Palladium‐catalyzed cross‐coupling of acid‐ and base‐unstable heteroatom‐functionalized organosilanes and C(sp2)X electrophiles such as aryl and alkenyl (pseudo)halides has been extensively studied. In contrast, little is known about the coupling between unactivated alkenyltrialkylsilanes and C(sp3)X electrophiles. Herein, the copper(I)‐promoted coupling of chromatographically stable alkenylbenzyldimethylsilanes with unreactive alkyl halides as well as allyl and benzyl halides is described. The reaction proceeds in the presence of CuI‐P(OEt)3 and Bu4NF⋅(tBuOH)4 to produce stereodefined di‐ and trisubstituted alkenes with complete retention of configuration.

Copper(I)-Promoted Alkylation of Alkenylbenzyldimethylsilanes. -The alkylation reagents can be alkyl, allyl, and benzyl halides. The stereochemical configuration on alkenyl groups is retained completely. The hydroxy group in alkenylsilanes is also tolerated. -(TAKEDA*, T.; MATSUMURA, R.; WASA, H.; TSUBOUCHI, A.; Asian J. Org. Chem. 3 (2014) 8, 838-841, http://dx.