Strong acid-catalyzed electrophilic ring expansion of oxetanes and sulfoxonium ylides

Halide-promoted pyridinylation of α-acylmethylides with 2-halo-1-methylpyridinium iodides as reagents

“…As the electron-withdrawing capability of the substituents on their α-position increases, their nucleophilicity decreases, while their stability increases. 5 α-Acyl sulfonium ylides—whether nucleophilic or electrophilic—have been generally exploited in the form of carbenes to fabricate and modify substructures, using reactions such as cyclization, 4 e ,6 ring expansion, 7 insertion, 8 coupling, 9 and methylation. 10 Normally, the dimethyl sulfide/dimethyl sulfoxide fragment in the sulfur ylides is usually spilt out as a leaving group and has been underutilized.…”

A ruthenium catalyzed Dolye–Kirmse rearrangement reaction of sulfoxonium ylides with sulfides or selenides

“…[11][12][13]27 Catalyzed by a transition metal, sulfoxonium ylides can smoothly form carbene and then participate in many reactions. [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] As carbene precursors, sulfoxonium ylides can be constructed in high yield using acyl chlorides or acid amides in one step under simple conditions. [44][45][46] The simple and convenient synthetic method allows sulfoxonium ylides to be easily obtained in a large scale even for industrial Scheme 1 Synthesis of β-keto phenyl thioethers and β-keto phenyl selenides.…”

Acid-catalyzed ring-expansion of 4-(1-hydroxycyclobutyl)-1,2,3-triazoles

“…On the other hand, a reaction of acid-catalyzed ring-expansion of a four-membered ring has also been reported recently. 17…”