Synthesis of Tetrasubstituted Alkenes by Tandem Metallacycle Formation/Cross-Electrophile Coupling.

Nickel-catalyzed cross-electrophile couplings have recently emerged as highly effective and practical methods for the formation of C-C bonds. By merging this process with well-established π-π coupling chemistry, a new method for the synthesis of tetrasubstituted alkenes has been developed. The procedure relies on the use of chlorosilanes as a means of generating reactive vinylnickel intermediates, which are capable of undergoing a reductive cross-electrophile coupling with alkyl halides. The method not only generates highly substituted allylic alcohol derivatives but also obviates the need for stoichiometric organometallic nucleophiles and provides greatly improved scope and functional group tolerance compared with previously developed methods.