Ruthenium(II)-Catalyzed Oxidative C-H Alkenylations of Sulfonic Acids, Sulfonyl Chlorides and Sulfonamides

摘要

Twofold CH functionalization of aromatic sulfonic acids was achieved with an insitu generated ruthenium(II) catalyst. The optimized cross-dehydrogenative alkenylation protocol proved applicable to differently substituted arenes and a variety of alkenes, including vinyl arenes, sulfones, nitriles and ketones. The robustness of the ruthenium(II) catalyst was demonstrated by the chemoselective oxidative olefination of sulfonamides as well as sulfonyl chlorides. Mechanistic studies provided support for a reversible, acetate-assisted CH ruthenation, along with a subsequent olefin insertion.