Ir(I)-Catalyzed Synthesis of Furanones from Vinyl Sulfoxonium Ylides

Abstract

A method for the synthesis of allyl substituted γ-butenolides via carbonyl ylide rearrangement of vinyl sulfoxonium ylide-derived carbenes has been developed. At rt, the mechanism involves a carbonyl ylide generation/allyloxy furan formation/[3,3]-sigmatropic rearrangement/isomerization sequence for the generation of 3-allyl butenolides. At 70 °C, instead of the final isomerization step, the resulting [3,3]-sigmatropic rearrangement product undergoes further [3,3]-sigmatropic rearrangement to produce 5-allyl butenolide. In the absence of the catalyst, the reaction affords a diene via [2,3]-sigmatropic rearrangement.

Insights into the multifaceted applications of vinyl sulfoxonium ylides

“…The sulfoxide group in 66 can take a proton from the α-position of the ketone followed by cope-type syn elimination giving the diene 64 . 41…”

Synthesis and Applications of π-Conjugation-Extended Vinyl Sulfoxonium Ylides

“…Most of these reactions, however, were restricted to α-keto sulfoxonium ylides. Since 2018, our group has been exploring the applications of stabilized vinyl sulfoxonium ylides in various transformations, such as cycloadditions, ylide formations, insertions, annulations, and rearrangement reactions . Recently, Zhang’s group developed an approach for the synthesis of phenols via [3 + 3] annulation of vinyl sulfoxonium ylides with cyclopropenones .…”

Divergent Synthesis of Tetrasubstituted Phenols via [3 + 3] Cycloaddition Reaction of Vinyl Sulfoxonnium Ylides with Cyclopropenones

“…For instance, the Hopmann group reported an iron-catalyzed [3 + 2] and [4 + 1] annulation reaction of vinyl sulfoxonium ylides with pyridines and amines to afford indolizines and pyrroles in 2018. Vaitla et al realized the synthesis of various allyl substituted butenolides via Ir-catalyzed carbonyl ylide generation from vinyl sulfoxonium ylide, followed by allyloxy furan formation/[3,3]-sigmatropic rearrangement . Subsequently, the same group developed an X–H (X = C, N, O, S, halogen) insertion of vinyl sulfoxonium ylide under metal-free conditions, which was applied to synthesize unsaturated oligoesters via sequential acid or ylide iteration (Scheme a) …”