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

Abstract

Two categories of tetrasubstituted phenols were prepared via the cycloaddition reaction of vinyl sulfoxonnium ylides with cyclopropenones in a switchable manner. Copper carbenoid was proposed as the active intermediate in the process of 2,3,4,5tetrasubstituted phenols formation, while 2,3,5,6-tetrasubstituted phenols were generated via the direct [3 + 3] annulation of vinyl sulfoxonnium ylides with cyclopropenones under metal-free conditions. Further synthetic applications were also demonstrated.

Insights into the multifaceted applications of vinyl sulfoxonium ylides

“…Very recently, the Zhang group reported a [3+3] cycloaddition reaction between vinyl sulfoxonium ylides 3 and cyclopropenones 52 to produce tetrasubstituted phenols under metal and metal-free conditions (Scheme 12). 36 The reaction affords selectively 2,3,4,5-tetrasubstituted phenols 53 under NHC-Cu catalyzed conditions and 2,3,5,6-tetrasubstituted phenols 54 were produced under metal-free conditions. Both the benzannulations gave moderate to excellent yields with different substituents at the vinyl sulfoxonium ylides and cyclopropenones.…”

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

“…However, general application of these inspiring systems often results in issues of selectivity, functional group compatibility, restricted substrate range, and atom-economy. Sulfoxonium ylides serve as very important and valuable building blocks, which shows significant synthetic potential and utility in transition-metal-catalyzed C–H bond activation and transformations . While these methods have witnessed tremendous advances on the traditional ionic-mechanism-based action models of sulfoxonium ylides, limited attention from chemists has been given to the exploration of their chemical properties in radical coupling and cyclization reactions possibly due to the dearth of reliable strategies for single-electron reduction of ylides (Scheme b, bottom) .…”

Synthesis and Applications of π-Conjugation-Extended Vinyl 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 . Despite these developments, we continued our search for new stabilized sulfoxonium ylides to further expand the scope of the sulfoxonium ylide-based transformations.…”