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

Stereoselective Three-Component Carbocyclization of 1,7-Enynes with Sulfoxonium Ylides and Water under Photoredox Catalysis

A visible-light-induced photoredox three-component carbocyclization reaction of 1,7-enynes with sulfoxonium ylides and water is reported. The protocol provides a facile entry to structurally valuable highly functionalized cyclopenta[c]quinoline scaffolds in a highly chemoselective and stereoselective manner. Salient features of this method include facile redox-neutral conditions, no requirement of base or other additive, and good functional-group tolerance.

Isocyanide-Based Multicomponent Reaction: Cascade α-Acyloxylation/Carboxamidation and [3 + 1+1] Cyclization of I(III)/S(VI)-Ylides

A metal-free cascade of α-acyloxylation/carboxamidation of I(III)/S(VI)-ylides, carboxylic acids, and isonitriles via a Passerini-like multicomponent reaction is reported. Unexpectedly, [3 + 1+1] cyclization involving I(III)/S(VI)-ylides and two molecules of ethyl isocyanoacetate was observed. The strategy allows for the synthesis of unsymmetrical α,α-disubstituted ketones and functionalized pyrroles with up to 99% yield and wide substrate compatibility. Notably, the procedure has been extended to the late-stage modification of drugs and natural products, offering an elegant complement to the classic Passerini reaction.

A Platform for the Synthesis of Diverse Phosphonyl and Thiofunctionalized Sulfoxonium Ylides

A practical strategy for the construction of diverse phosphonyl and thiofunctionalized sulfoxonium ylides via controllable monofunctionalization of hybrid I(III)/S(VI) ylides is presented. This process allows efficient P-H insertion of I(III)/S(VI) ylides under Cu catalysis, enabling the synthesis of phosphonyl sulfoxonium ylides, whereas reaction with sulfur-containing reagents including AgSCF3, KSC(S)OR, and KSCN under mild conditions resulted in α-trifluoromethylthiolation, dithiocarbanation, and thiocyanation of sulfoxonium ylides accordingly. Of note, wide substrate compatibility (108 examples), excellent efficiency (up to 99% yield), gram-scale experiments, and various product derivatizations highlight the synthetic utility of this protocol.

Divergent Approach to Highly Substituted Arenes via [3 + 3] Annulation of Vinyl Sulfoxonium Ylides with Ynones

Herein, we report the divergent benzannulation for highly substituted arenes using vinyl sulfoxonium ylides and ynones. The addition of ynone at the γ-position of vinyl sulfoxonium ylides leads to dienyl sulfoxonium ylide that can undergo selective annulation under different conditions to give m-terphenyls and parabens. Moreover, control experiments and quantum chemical calculations reveal two distinct reaction mechanisms for both annulations.

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

Herein, we report the synthesis of π-conjugation-extended vinyl sulfoxonium ylides from vinyl sulfoxonium ylide and electron-deficient alkynes. The new dienoate ylides are used in various transformations, such as X-H (X = S, O) insertion, halogenation, carbene-mediated transformation, and radical-mediated reductions to obtain a variety of conjugated dienoates.

Insights into the multifaceted applications of vinyl sulfoxonium ylides

Sulfoxonium ylides are important synthetic precursors in various organic transformations. Their synthetic potential was well explored in the synthesis of various bioactive natural products and pharmaceuticals. Vinyl sulfoxonium ylide is a stabilized sulfoxonium ylide containing an electron-deficient alkene at the ylidic carbon. Similar to α-keto sulfoxonium ylides, these reagents can generate vinyl carbenes in the presence of metals under suitable conditions. These vinyl carbenes can be used for various organic transformations such as X-H (X = C, N, O, S) insertions, annulations, and rearrangement reactions. Due to the dipole structure of the vinyl sulfoxonium ylide, it can undergo electrophilic addition with electrophiles at the α-position. These reagents are used as synthons for various aromatic and heteroaromatic compound syntheses. Moreover, their stability and convenient handling make them potential replacements for thermally less stable vinyl diazo compounds. Herein, we provide an overview of early efforts in this area, with particular emphasis on our own recent development of vinyl sulfoxonium ylide-mediated transformations in the presence and absence of metal catalysis, and also give personal perspectives on the challenges and future scope for improving the application of vinyl sulfoxonium ylides.