Efficient Stereoselective Alkenylation through a Homolytic Domino Reaction Involving a 1,5 Sulfur-to-Carbon Translocation

摘要

Although being of great power when applied to C(sp~2) electrophiles, transition metal-catalyzed cross-couplings suffer from basic limitations in the case of C(sp~3) electrophiles, especially of those possessing β-hydrogen atoms. Indeed, while encouraging advancements in the cross-coupling of C(sp~2) nucleophiles with primary alkyl electrophiles have been recently described, the couplings of less active secondary alkyl halides or sulfonates were unsuccessful, except for a few atypical cases. Far better results were obtained by employing homolytic proximal addition-elimination of secondary carbon-centered radicals to stannyl-, sulfonyl-, or sulfinylalkenes