[3,3]‐Sigmatropic Rearrangement of Aryl Fluoroalkyl Sulfoxides with Alkyl Nitriles

Abstract

Herein we report the ortho‐cyanoalkylation of aryl fluoroalkyl sulfoxides with alkyl nitriles. The reaction proceeds through an “assembly/deprotonation” triggered [3,3]‐rearrangement and allows the incorporation of two valuable functional groups including the cyano group and difluoromethylthio group into arenes. As a consequence, a wide range of ortho‐cyanoalkylated difluoromethylthio arenes were produced with high efficiency under mild and environmentally friendly conditions. Remarkably, the reaction proceeds smoothly with the electron‐donating group substituted arenes which can be challenging to the reaction of non‐fluoroalkyl sulfoxides. This beneficial effect can be attributed to the unique electronegativity of fluoroalkyl substituents.

Synthesis of gem‐Difluorinated Keto‐Sulfoxides from Sulfoxonium Ylides

“…A similar protocol, reported by Browne and collaborators, employed the mechanochemistry to achieve the same compounds [17] . Independly, Peng and collaborators reported the synthesis of gem ‐difluorinated sulfoxides from the sulfides described above, by using m‐ CPBA in DCM [18] . By combining these methods, the gem ‐difluorinated sulfoxides can be obtained in 3 steps.…”

“…[17] Independly, Peng and collaborators reported the synthesis of gem-difluorinated sulfoxides from the sulfides described above, by using m-CPBA in DCM. [18] By combining these methods, the gem-difluorinated sulfoxides can be obtained in 3 steps. Recently, Hanquet and Leroux developed the deprotonative functionalization of α,α-difluoromethylsulfoxide with aldehydes, using a catalytic superbase (P 4 -tBu) and a silane additive, to provide β-hydroxysulfoxides.…”