Tracking SF<sub>5</sub>I in the Iodopentafluorosulfanylation of Alkynes
Thi Mo Nguyen, Claude Y. Legault, Nicolas Blanchard, Vincent Bizet, Dominique Cahard
Abstract
Abstract In the vibrant field of SF 5 chemistry, SF 5 X reagents (X=F, Cl, Br) are at the heart of current investigations in radical pentafluorosulfanylation reactions. SF 5 I is the missing link whose existence has not been reported despite its potential as SF 5 donor. This study reports the formal addition of the hitherto unknown SF 5 I reagent to alkynes by means of a combination of SF 5 Cl/KI/18‐crown‐6 ether. The exclusive regio‐ and stereoselective synthesis of unprecedented ( E )‐1‐iodo‐2‐(pentafluoro‐λ 6 ‐sulfanyl) alkenes was achieved. A consensus was reached through computational and mechanistic studies for the realistic formation of SF 5 − anion but not SF 5 I in solution and the rational involvement of SF 5 ⋅ and iodine radicals in the iodo pentafluorosulfanylation reaction.