Synthesis of (E)-β-Selenovinyl Sulfones through a Multicomponent Regio- and Stereospecific Selenosulfonation of Alkynes with Insertion of Sulfur Dioxide

Abstract

A novel and practical method for the selenosulfonation of alkynes with the insertion of sulfur dioxide has been developed. A series of β-(seleno)vinyl sulfones with high levels of regio-and stereoselectivity have been prepared. The key features of this reaction include a broad substrate scope, excellent functional-group tolerance, and amenability to scale-up synthesis. A plausible radical mechanism is proposed to illustrate this reaction.

Regio- and stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction

“…A series of novel approaches to functionalized organoselenium compounds was developed recently [23][24][25][26][27][28][29]. Among these is an elegant, highly effective approach that led to β-hydroxy, β-mercapto, and β-amino-substituted diorganyl diselenides and selenides.…”

“…The methodology based on bis(trimethylsilyl)selenide was also successfully applied to the synthesis of functionalized asymmetric alkyl-and vinyl selenides, including cyclic disubstituted 1,3thiaselenolane and trisubstituted thiaselenane [26,27]. Vinyl selenides represent a very interesting class of compounds with a wide range of synthetic applications [28,29].…”

Synthesis of Seleno‐Heterocycles via Electrophilic/Radical Cyclization of Alkyne Containing Heteroatoms

“…The four-component selenosulfonation of alkyne is shown in Scheme 92. [157] Various aryl diazonium tetrafluoroborates with different functional groups were used including electron-donating (OMe), electron-neutral (H), and electron-withdrawing (F and Cl) delivering the corresponding products in high yield.…”

Metal‐Free Multi‐Component Sulfur Dioxide Insertion Reaction Leading to Quinoxalin‐2‐One‐Containing Vinyl Sulfones under Visible‐Light Photoredox Catalysis

“…In 2018, Wu and co‐workers also described three‐component reaction of alkynes, potassium alkyltrifluoroborates, and DABCO ⋅ (SO 2 ) 2 leading to ( E )‐vinyl sulfones in the presence of copper(II) triflate and photocatalysis (Scheme 1b) [12] . The same year, Sun and co‐workers reported K 2 S 2 O 8 mediated selenosulfonation of alkynes to access ( E )‐ β‐ selenovinyl sulfones through the insertion of sulfur dioxide with DABCO ⋅ (SO 2 ) 2 (Scheme 1c) [13] . Despite the notable progress in these elegant sulfur dioxide insertion methods, there is still great demand to develop mild, green and efficient strategy for the construction of complex and important multisubstituted vinyl sulfones from simple and readily accessible starting materials.…”