The conversion of CF3-alkenes to
gem-difluoroalkenes using reductive cross-coupling strategy has
received much attention in recent years, however, the use of green and
readily available reducing salt to mediate these reactions remains to be
explored. In this work a concise construction of
gem-difluoroalkenes, which requires neither a catalyst nor a
metal reducing agent, was established. Rongalite, a safe and inexpensive
industrial product, was employed as both a radical initiator and
reductant. This procedure was compatible with both linear and cyclic
diaryliodonium salts, enabling a wide variety of substrates
(>70 examples). The utility of this approach was
demonstrated through gram-scale synthesis and efficient late-stage
functionalizations of anti-inflammatory drugs.
|