Direct and Efficient Synthesis of Sulfonium Acyl Sulfonylmethylide Ylides from Acetylenic Sulfones and Dimethyl Sulfoxide

Abstract

Bifunctionalized sulfonium ylides, sulfonium acyl sulfonyl methylides, were directly and efficiently prepared from various acetylenic sulfones and aliphatic sulfoxides under heating conditions. The current method features short reaction time, low cost, readily available starting materials, convenient operation and purification, providing an efficient access to widely applied bifunctionalized sulfonium ylides.

Synthesis of Sulfo(xo)nium Diacylmethylides

“…[56] After three decades, Xu's group reported a direct and efficient protocol to synthesize sulfonium α-acyl-α-sulfonylmethylides 85 in 36-98 % yields from various acetylenic sulfones 84 with sulfoxides (Scheme 21b). [57] In contrast to Hanack's work, the later protocol features short reaction time, convenient operation and purification. The products are easily obtained on a gram scale by simple recrystallization without column chromatography.…”

Tf2O/2-Chloropyridine-Triggered Synthesis of Benzo[b]thiophene 1,1-Dioxides from Sulfonium α-Acyl Sulfonylmethylides

“…Sulfonium α-acylmethylides are shelf-stable reagents, which are excellent choices to achieve those tasks . Trifluoromethanesulfonic (triflic) anhydride as a potent electrophilic reagent can effectively convert the acyl group into the active vinyl triflate .…”

Demethyl oxidative halogenation of diacyl dimethylsulfonium methylides

“…11 b They also underwent demethyl hydrogenation in the presence of trifluoroacetic acid or dimethyl sulfoxide. 13 α-Halo-α-methylthio-β-ketosulfones containing a quaternary carbon stereocenter serve as versatile building blocks and methylthio sulfonyl carbene precursors. 14 We envisioned that they should be prepared via demethyl oxidative halogenation of our α-acyl-α-sulfonyl and α,α-diacyl dimethylsulfonium methylides with halogenating reagents (Scheme 1d).…”

“…On the basis of the control experiments and the literature, 13,15 possible mechanisms are proposed (Scheme 6). For chlorination, sulfur ylides 1 can exist in zwitterionic forms 1′ .…”