Visible-light initiated direct oxysulfonylation of alkenes with sulfinic acids leading to β-ketosulfones

Abstract

Highly efficient visible-light initiated direct oxysulfonylation of alkenes with sulfinic acids leading to β-ketosulfones has been realized under metal-free conditions.

A Convenient Synthesis of Sulfones via Light Promoted Coupling of Sodium Sulfinates and Aryl Halides

“…Classical methods for the preparation of sulfones [7] include the oxidation of sulfides, [8] electrophilic aromatic sulfonylation with sulfonyl chlorides, [9] transition metal catalyzed cross coupling of arylsulfinates and aryl halides, [10][11][12] and the insertion of sulfur dioxide. [14] The sulfonyl radicals are usually in-situ generated from sulfinic acid, [15] sodium sulfinate, [16] sulfonyl chloride, [17] sulfonyl hydrazide, [18] and SO 2 [19] promoted by photo-catalysts or oxidants. [14] The sulfonyl radicals are usually in-situ generated from sulfinic acid, [15] sodium sulfinate, [16] sulfonyl chloride, [17] sulfonyl hydrazide, [18] and SO 2 [19] promoted by photo-catalysts or oxidants.…”

“…[24] In the latter two reactions, the anions were proposed as the electron donors. Other bases such as K 2 CO 3 , Na 2 CO 3 and CsF were also applicable and 3 a was obtained in moderate to good yields (entries [13][14][15]. Herein, we report a new strategy for the synthesis of sulfones via the formation of EDA complexes from sodium sulfinates and aryl halides.…”

“…[13] Recently, the reactions of sulfonyl radicals have received significant consideration in terms of synthetic efficiency and atom economy. [14] The sulfonyl radicals are usually in-situ generated from sulfinic acid, [15] sodium sulfinate, [16] sulfonyl chloride, [17] sulfonyl hydrazide, [18] and SO 2 [19] promoted by photo-catalysts or oxidants. Most of these methods encounter certain limitations including over-stoichiometric amounts of oxidants, harsh acid conditions, high reaction temperatures, and extra addition of metal-catalyst or photo-catalyst.…”

“…To our delight, when Cs 2 CO 3 was added, the yield of 3 a was increased to 80% (entry 12). Other bases such as K 2 CO 3 , Na 2 CO 3 and CsF were also applicable and 3 a was obtained in moderate to good yields (entries [13][14][15]. Organic base Et 3 N led to a poor yield (entry 16).…”

Visible Light‐Induced Synthesis of Biscoumarin Analogs under Catalyst‐Free Conditions

“…CFL light intensity is harmless and an easily available energy source. CFL light intensity proved to be a very useful source in the synthesis of unsymmetrical diynes , cyclocondensation of pyrrole , photocatalytic generation of H 2 , carboxylation , synthesis of 1,2‐diketones , trifluromethylated alkenes , diaryl disulfides , oxysulfonylation of alkenes , 3,4‐dithiophenes , benzothiazoles , photochromic molecules , iron(III)‐based metal organic frame works , and photocatalyst .…”