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A one-step method to convert nitroarenes into aryl sulfones under operationally simple, transition-metal-free conditions is described. A range of nitroarenes were reacted with sodium sulfinates and caesium carbonate in N , N ′-dimethylpropyleneurea to afford aryl sulfones in up to 83% yield. [ABSTRACT FROM AUTHOR]

The work presented here investigates whether the TpMesFe+ moiety, which had been previously found to mediate the dioxygenation of cysteine and cysteamine, can do the same with simple thiols, which are not functionalized by an amine group. Accordingly, the complexes TpMesFeSR (R=Ph, iPr) were synthesized and after full characterization exposed to O2. They were found to react unselectively to yield sulfinates, disulfides, and thiosulfones as products. The sulfinate complex TpMesFeO2S‐p‐Tol was prepared independently and found to be air‐stable, suggesting that the additional products are not formed via overoxidation or subsequent reactions of coordinated sulfinate product. To investigate whether the larger reaction space, opened up due to the missing amine donor is responsible, a Tp‐ligand functionalized by a pyridyl donor was employed. A corresponding Tp‐iron(II) chlorido complex was prepared and converted through salt metathesis reactions into the respective thiolate analogues, which were fully characterized and structurally authenticated. However, subsequent O2 reactivity studies did not show an improved selectivity. The reason may lie in a more open reaction pocket in combination with an electronic situation which is less ideal than in case of TpMesFe(cysteamine). [ABSTRACT FROM AUTHOR]

In synthetic carbohydrate chemistry, the modification of glycosyl radicals pathway stands as a central area of focus. The radical‐based reactions often demonstrate remarkable compatibility with various functional groups owing to the mild initiation conditions. In particular, the identification of novel glycosyl radical precursors, combined with advanced reaction techniques, has substantially broadened the scope of glycosyl compound synthesis. Despite the presence of versatile donors, the synthesis of noble donors is still addressed as a synthetic need and challenges associated with sugar chemistry. Currently, a new class of glycosyl radical precursors has been developed which enables the production of C‐, S‐, O‐, and N‐glycosides efficiently. In this light, we highlight strategies towards bench‐stable glycosyl sulfoxides, sulphone, and sulfite donors that can enable the site‐, regio‐ and stereoselective transformation of protected or naked sugar synthons in synthetic carbohydrate chemistry. Here, this review article covers the recent developments in the selective glycosyl radical diversification such as glycosyl alkylation, arylation, alkenylation, sulfuration, C−H activation, and DNA conjugation via the bench‐stable donors along with mechanistic aspects, challenges, and future directions. [ABSTRACT FROM AUTHOR]

β‐Ketosulfones were synthesized from enol acetates and sodium sulfinates under electrochemical conditions. The starting sulfinates can act both as the supporting electrolyte and as the source of S‐centered radicals, allowing electrolysis to proceed without external salt. Side reactions of enol acetates' oxidation are not observed, and the developed process is quite selective. The proposed electrochemical sulfonylation is compatible with a wide range of the initial enol acetates and sulfinates. On the basis of literature data, control experiments, and CV studies, the presumable reaction pathway is suggested. The key intermediates are S‐centered sulfonyl radical, C‐centered benzylic radical, and β‐acetoxy‐β‐hydroxysulfone. [ABSTRACT FROM AUTHOR]

A visible‐light‐initiated energy‐transfer enabled radical cyclization for the divergent synthesis of polycyclic γ‐sultine derivatives has been developed. The reaction provides an alternative and expeditious access to benzofused γ‐sultine frameworks, the analogues of γ‐lactones and γ‐sultones, and features good functional group compatibility, mild reaction conditions and excellent diastereoselectivity. The robustness and application potential of this method have also been successfully displayed by two gram‐scale reactions and the synthesis of polycyclic sultones. Mechanistic studies indicated the transformations through a possible energy‐transfer enabled intramolecular radical homolytic substitution or hydrogen atom transfer process mainly. [ABSTRACT FROM AUTHOR]

Previous N‐glycosylation approaches have predominately involved acidic conditions, facing challenges of low stereoselectivity and limited scope. Herein, we introduce a radical activation strategy that enables versatile and stereoselective N‐glycosylation using readily accessible glycosyl sulfinate donors under basic conditions and exhibits exceptional tolerance towards various N‐aglycones containing alkyl, aryl, heteroaryl and nucleobase functionalities. Preliminary mechanistic studies indicate a pivotal role of iodide, which orchestrates the formation of a glycosyl radical from the glycosyl sulfinate and subsequent generation of the key intermediate, a configurationally well‐defined glycosyl iodide, which is subsequently attacked by an N‐aglycone in a stereospecific SN2 manner to give the desired N‐glycosides. An alternative route involving the coupling of a glycosyl radical and a nitrogen‐centered radical is also proposed, affording the exclusive 1,2‐trans product. This novel approach promises to broaden the synthetic landscape of N‐glycosides, offering a powerful tool for the construction of complex glycosidic structures under mild conditions. [ABSTRACT FROM AUTHOR]

Carbenoid insertion into boronate carbon‐boron bonds, namely the Matteson‐type homologation, has been recognized as a powerful tool for constructing carbon‐carbon bonds. However, some limitations and inconvenience still exist with the carbenoids currently employed, such as the use of highly cryogenic and basic conditions. Herein, we report a new class of stable carbenoids with sulfinate as nucleofuge for Matteson‐type homologations, which directly introduce O‐ and N‐substituted methylenes into carbon‐boron bonds. Enabled by oxazaborolidines as the boronic substrates, the reaction is operatable at 0 °C or room temperature with weaker bases. Broad functional groups, including acidic C−H bonds, can be tolerated. The synthetic utility of this method has been demonstrated in the gram‐scale synthesis and iterative insertion of various carbenoids. [ABSTRACT FROM AUTHOR]

An efficient and operationally simple method for the synthesis of β-keto sulfones through the BF3·OEt2-promoted reaction of alkynes and sodium sulfinates is developed. With its facile and selective access to the targets, it features good functional group compatibility, mild conditions, easily available starting materials, and good yields. Notably, the reaction does not require metal catalysts or chemical reagents with pungent odors. [ABSTRACT FROM AUTHOR]

Chiral γ-keto sulfones are significant structures in both organic synthesis and pharmaceutical chemistry. Although there are many choices for obtaining racemic forms, only a few enantioselective methods have been reported. We have developed a simple way for obtaining chiral γ-keto sulfones in moderate yields and moderate enantiomeric ratios. Readily available sulfinates were directly used as substrates that could be converted into sulfinic acids by treatment with boric acid. The bifunctional catalyst forms a chiral ion pair with the sulfinic acid and controls the enantioselectivity of the sulfonation through hydrogen bonding. [ABSTRACT FROM AUTHOR]

An efficient cross-coupling of aryl bromides with sodium sulfinates, using an organoboron photocatalyst with nickel, is described herein. Under the irradiation of white light, this dually catalytic system enables the synthesis of a series of sulfone compounds in moderate to good yields. A broad range of functional groups and heteroaromatic compounds is tolerated under these reaction conditions. The use of an organoboron photocatalyst highlights a sustainable alternative to iridium or ruthenium complexes. These findings contribute to the field of photochemistry and provide a greener approach to sulfone synthesis. [ABSTRACT FROM AUTHOR]

Sulfur-containing scaffolds originating from small alkyl fragments play a crucial role in various pharmaceuticals, agrochemicals, and materials. Nonetheless, their synthesis using conventional methods presents significant challenges. In this study, we introduce a practical and efficient approach that harnesses hydrogen atom transfer photocatalysis to activate volatile alkanes, such as isobutane, butane, propane, ethane, and methane. Subsequently, these nucleophilic radicals react with SO2 to yield the corresponding sulfinates. These sulfinates then serve as versatile building blocks for the synthesis of diverse sulfur-containing organic compounds, including sulfones, sulfonamides, and sulfonate esters. Our use of flow technology offers a robust, safe and scalable platform for effectively activating these challenging gaseous alkanes, facilitating their transformation into valuable sulfinates. Sulfur-containing scaffolds originating from small alkyl fragments play a crucial role in various pharmaceuticals, agrochemicals, and materials, but their synthesis presents significant challenges. Herein, the authors report the photocatalytic conversion of C(sp3)–H bonds originating from lightweight alkanes into alkyl sulfinates, employing SO2. [ABSTRACT FROM AUTHOR]

This paper presents a green and efficient aqueous‐phase method for the synthesis of thiosulfonates, which has the benefits of no need for catalysts or redox reagents and a short reaction time, providing a method with great economic value for synthesizing thiosulfonates. Furthermore, 3‐Sulfenylindoles can be easily synthesized using this method, which expands the potential applications of this reaction. [ABSTRACT FROM AUTHOR]

Hydroiodic acid‐mediated vicinal iodosulfonylation reaction of alkynes with sodium sulfinates is proposed for the synthesis of (E)‐β‐iodovinyl sulfones. The method is easy to operate, environmentally friendly, using inexpensive and easily available raw materials, and giving the target products with good regio‐ and stereoselectivity in satisfactory yields. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of sulfinate addition‐responsive fluorescent molecules are described. We found that addition reaction of sulfinates to naphthalimide‐substituted azocarboxylates afforded the corresponding sulfonyl hydrazides with high fluorescence quantum yields (up to 0.91 in THF and 0.54 in methanol), which exhibited a large Stokes shift (105 nm) in protic methanol solvent, while the unsubstituted hydrazide and the sulfonyl‐position isomer showed no fluorescence in polar solvents. [ABSTRACT FROM AUTHOR]

Sulfonyl groups are widely observed in biologically relevant molecules and consequently, SO2 capture is an increasingly attractive method to prepare these sulfonyl‐containing compounds given the range of SO2‐surrogates now available as alternatives to using the neat gas. This, along with the advent of photoredox catalysis, has enabled mild radical capture of SO2 to emerge as an effective route to sulfonyl compounds. Here we report a photoredox‐catalyzed cross‐electrophile sulfonylation of aryl and alkyl bromides making use of a previously under‐used amine‐SO2 surrogate; bis(piperidine) sulfur dioxide (PIPSO). A broad selection of alkyl and aryl bromides were photocatalytically converted to their corresponding sulfinates and then trapped with various electrophiles in a one‐pot multistep procedure to prepare sulfones and sulfonamides. [ABSTRACT FROM AUTHOR]

This review disclosed synthetic approaches to sulfonyl amides from non‐sulfonyl halogenated precursors. Known methods were systematized into groups and subgroups according to the type of starting organosulfur compound. Thiols, disulfides, and sulfonamides form a group of S(II)‐containing precursors, which are used in oxidative amination reactions. An important and versatile group for oxidative amination is represented with S(IV)‐containing compounds, i. e., sufinates, sulfinamides, DMSO, N‐sulfinyl‐O‐(tert‐butyl)hydroxylamine, etc. A series of S(VI)‐containing precursors for amination reactions (except sulfonyl halides) include sulfonic acids, sulfonyl azides, thiosulfonates, and sulfones. All approaches are represented with the most prominent examples of the resulting sulfonamides, which could be obtained in high yields mostly via short reaction sequences. Promising electrochemical methods for the preparation of sulfonamides from thiols, disulfides, sulfonamides, sulfinic acid derivatives, and dimethyl sulfoxide under mild and green conditions are also highlighted. [ABSTRACT FROM AUTHOR]

An electrooxidative C−H functionalization is a widely accepted route to obtain sulfur‐containing arenes and heteroarenes. However, this process often involves using non‐recyclable supporting electrolytes, (co)solvents like hexafluoroisopropanol, additives like acid, or catalysts. The use of additional reagents can increase costs and waste, reducing atom efficiency. Moreover, unlike other nitrogen‐containing heterocycles, there have only been sporadic reports of electrochemical C−H functionalization in fused pyrimidin‐4‐ones, and an electrolyte‐free process has yet to be developed. This work demonstrates that such anodic coupling reactions can be performed in an all‐green electrolytic system without using such additional electrolytes or HFIP, maintaining a high atom economy. This C−H functionalization strategy utilizes inexpensive sodium sulfinates and ammonium thiocyanate as sulfonylating and thiocyanating agents in an undivided cell at a constant current, using a mixture of CH3CN/H2O as solvent at room temperature. Thus, fused pyrimidin‐4‐ones can be selectively converted into C3‐sulfonylated and ‐thiocyanated derivatives in moderate to good yields. [ABSTRACT FROM AUTHOR]

Allyl sulfones are an essential pharmacophore in many bioactive compounds. To combat their synthetic barrier, we report a practical, straightforward organophotocatalyzed methodology for accessing miscellaneously functionalized allyl sulfone derivatives using inexpensive and bench‐stable sodium sulfinate salts under mild conditions. This photo‐catalyzed radical sulfonylation provides access to a variety of allyl sulfones in good to excellent yields with high E : Z selectivity. A wide range of vinyl cyclopropanes, as well as aryl/hetero and alkyl sodium sulfinates, were tolerated and reliable in gram‐scale synthesis. Later on, further functionalization of allyl sulfones was demonstrated. A plausible mechanism for radical sulfonylation is proposed from the control experiments. [ABSTRACT FROM AUTHOR]

Direct and site-selective C-H functionalization of alkenes under environmentally benign conditions represents a useful and attractive yet challenging transformation to access value-added molecules. Herein, a unified protocol for a variety of intermolecular Heck-type functionalizations of Csp2-H bond of alkenes has been developed by thianthrenation. The reaction features metal-free and operationally simple conditions for exclusive cine-selective C-H functionalization of aliphatic and aryl alkenes to forge C-C, C-N, C-P, and C-S bonds at room temperature, providing a general protocol for intermolecular Heck-type reaction of alkenes with nucleophiles (Nu = sulfinates, cyanides, amines, amides). Alkenes undergo cine-sulfonylation, cyanation, amination to afford alkenyl sulfones, alkenyl nitriles and enamines. Direct and site-selective C–H functionalization of alkenes under environmentally benign conditions represents a useful and attractive yet challenging transformation to access value-added molecules. Here, the authors report a protocol for a variety of intermolecular Heck-type functionalization of C(sp2)–H bond of alkenes by thianthrenation. [ABSTRACT FROM AUTHOR]

Impressive progress has been made in the copper‐catalyzed asymmetric propargylic substitution (APS) reaction, but its use in remote asymmetric yne‐allylic substitution remains a challenging topic. Herein, we report the first remote enantioselective copper‐catalyzed sulfonylation of yne‐allylic esters with sodium sulfinates. The reaction is assumed to occur via a copper‐vinylvinylidene species as the key reactive intermediate. The use of readily available starting materials, the mild reaction conditions, and the excellent regio‐, enantio‐ and stereoselectivity, as well as broad substrate scope (>70 examples), show the practicality and attractiveness of this method. [ABSTRACT FROM AUTHOR]

An I2/PPh3‐mediated synthesis of 3‐thiolated chromones starting from 2‐hydroxyphenylenones and sodium sulfinates was reported. This method features one pot manner, metal‐free, easy performance, readily available starting materials and illustrating potential value for some biologically or pharmaceutically active compounds. In addition, a possible mechanism was proposed based on the control experiments. [ABSTRACT FROM AUTHOR]

Herein, we present a remarkably efficient, highly diastereoselective organophotoredox-catalyzed hydrosulfonylation of cyclopropenes. This method employs sodium sulfinates to successfully construct poly-substituted sulfonated cyclopropane derivatives. To enhance the applicability of this transformation, we demonstrate its broad applicability across a wide range of substrates, its scalability for large-scale synthesis, and its compatibility with late-stage functionalization. Notably, this late-stage functionalization protocol exhibits good tolerance toward diverse functional groups. Its operational convenience further adds to its appeal, providing access to valuable building blocks that hold great significance in drug discovery and medicinal chemistry. [ABSTRACT FROM AUTHOR]

We present a convenient and efficient deoxygenation method for synthesizing disulfides and thioethers. The reaction involves an iodide-catalyzed reduction of methyl sulfinates or sulfoxides, respectively, employing formic acid as a stoichiometric reductant. The methodology demonstrates excellent yields and remarkable orthogonality towards other reducible functional groups. In silico explorations revealed the synergistic action of formic acid and in situ generated hydroiodic acid as Brønsted donors within a formic acid framework. This molecular arrangement activates the sulfinyl group and promotes subsequent deoxygenation. Notably, this approach enables the deoxygenation of sulfur-based functional groups using formic acid as the stoichiometric reductant without needing transition metals or strong acidic media such as hydroiodic acid. Overall, this methodology contributes to the advancement of the reduction of diverse oxygenated sulfur-containing compounds in a sustainable approach. [ABSTRACT FROM AUTHOR]

An efficient procedure has been developed under microwave irradiation for the monosulfonylation of amines in acetonitrile:water. In this reaction, equimolar quantities of amines and sodium sulfinates were reacted in presence of CuBr2 and omitted the use of oxidants, ligands, additives, and bases. The developed methodology converts a wide array of sterically and electronically diverse sulfinate and amines into the corresponding sulfonamides in excellent yields within a short reaction time. The use of microwave and aqueous media makes this protocol potentially useful in the development of a green strategy for the synthesis of sulfonamides. [ABSTRACT FROM AUTHOR]

Sulfones are fascinating and highly used functional groups, but current syntheses still have limitations. Here, a regiodivergent transition metal-free approach towards sulfones [(E)-allylic sulfones and α-sulfonylmethyl styrenes] is reported. The method employs commercially available olefins, bases, additives, solvents, and sodium sulfinates (RSO2Na) and produces adducts in good yields. Considering that up to 4 reactions (bromination, dearomative rearrangement, E2, and SN2) are happening, this approach is very efficient. The structures of key adducts were confirmed by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Keywords: organic electrochemistry; indoles; 3-sulfonylindoles; oxidation; sodium sulfinates; alkynylanilines EN organic electrochemistry indoles 3-sulfonylindoles oxidation sodium sulfinates alkynylanilines 2959 2968 10 08/31/23 20230915 NES 230915 Graph Indoles exist ubiquitously in pharmaceuticals, agrochemicals, and natural products, and are among the most important nitrogen-containing heterocycles. HRMS-ESI: I m i / I z i [M + Na] SP + sp calcd for C SB 29 sb H SB 22 sb N SB 2 sb O SB 4 sb S SB 2 sb Na: 549.0913; found: 549.0915. HRMS-ESI: I m i / I z i [M + Na] SP + sp calcd for C SB 28 sb H SB 20 sb N SB 2 sb O SB 4 sb S SB 2 sb Na: 535.0757; found: 535.0753. HRMS-ESI: I m i / I z i [M + Na] SP + sp calcd for C SB 29 sb H SB 22 sb F SB 3 sb NO SB 4 sb S SB 2 sb Na: 592.0835; found: 592.0839. [Extracted from the article]

Keywords: sulfinate; sulfenylation; iodine; microwave heating; heterocycles; thiolation EN sulfinate sulfenylation iodine microwave heating heterocycles thiolation 1723 1726 4 08/18/23 20230901 NES 230901 Graph Organic sulfur compounds, especially thioethers, are prominent structural motifs in many bioactive natural products, pharmaceuticals, materials, and agrochemicals. [7] In 2018, the Song group developed a difunctionalization of an imidazopyridine by using a sodium sulfinate and iodine (Scheme 1)..[8] With the base and iodine, they obtained the sulfonylated product exclusively, whereas with iodine and a reducing agent (PPh SB 3 sb ), they obtained the sulfenylated product exclusively. However, the reaction of B 1a b with B 2a b in Et SB 2 sb O as a solvent under basic conditions at 100 °C for 20 hours gave the 3-phenylsulfonylated product B 4a b in only 50% conversion, along with 50% of the 3-iodo compound B 5 b (Table 1, entry 1). [Extracted from the article]

We report a general approach to highly functionalized (Z)-allylic amines by decarboxylative allylation of vinyloxazolidin-2-ones. This process engages sodium sulfinates as nucleophiles to form a new carbon–sulfur bond, utilizing a palladium catalyst generated from Pd(OAc)2 and diphosphine ligand dpppe. The scope of the protocol is illustrated by the synthesis of 30 representative allylic amines with high regio- and stereoselectivity. Mechanistic studies show that the Z-selectivity of the reaction stems from the formation of a palladacycle intermediate through Pd–N chelation. The synthetic utility of this method was further exemplified by the gram-scale synthesis and subsequent transformations to various compounds. [ABSTRACT FROM AUTHOR]

These results demonstrated that the direct reduction of sulfinyl sulfone by Hantzsch ester was not likely to happen and the necessity of both acetyl chloride and Hantzsch ester for the reuse of sulfonyl radicals. SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 7.67 (dd, I J i = 5.0, 1.4 Hz, 1 H), 7.64 (dd, I J i = 5.3, 1.3 Hz, 1 H), 7.39 (dd, I J i = 3.9, 1.4 Hz, 1 H), 7.23 (dd, I J i = 3.7, 1.3 Hz, 1 H), 7.10 (dd, I J i = 5.4, 3.7 Hz, 1 H), 7.04 (dd, I J i = 5.0, 3.8 Hz, 1 H). SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 7.61 (d, I J i = 8.4 Hz, 1 H), 7.58 (d, I J i = 2.1 Hz, 1 H), 7.51 (d, I J i = 8.5 Hz, 1 H), 7.39 (d, I J i = 2.2 Hz, 1 H), 7.30 (dd, I J i = 8.4, 2.2 Hz, 1 H), 7.25 (dd, I J i = 8.5, 2.1 Hz, 1 H). Keywords: sulfoxides; sulfinyl radicals; thiosulfonates; radical reaction; reductive coupling EN sulfoxides sulfinyl radicals thiosulfonates radical reaction reductive coupling 2487 2494 8 07/31/23 20230817 NES 230817 Graph Organosulfur compounds exist widely in natural products, agrochemicals, and pharmaceuticals, with sulfur being the fifth most used element in approved drugs followed by carbon, hydrogen, oxygen, and nitrogen. [Extracted from the article]

A direct C−H bond oxidative sulfonylation of β‐alkyl cyanoalkenes with sodium sulfinates was reported. This transformation involves the use of a copper salt catalyst, along with a catalytic amount of I2 and DMSO as the oxidative system, which provides a straightforward and practical access to various cyanoallyllic sulfones. [ABSTRACT FROM AUTHOR]

A facile and practical silver-mediated radical cascade cyclization of N-allylamides with sodium sulfinates is developed, giving a series of sulfonated oxazolines in moderate to good yields. This transformation involves a radical process via intermolecular sulfonylation of alkenes and intramolecular cyclization. This reaction system could be also applied to access sulfonated dihydrofurans. [ABSTRACT FROM AUTHOR]

C-Glycoside analogs of naturally occurring glycoconjugates are useful tools for chemical biology studies, but their synthesis usually requires protection of the hydroxyl groups of the glycosyl donors. Here we report protecting-group-free and photoredox-catalyzed C-glycosylation with glycosyl sulfinates and Michael acceptors via the Giese radical addition. [ABSTRACT FROM AUTHOR]

The subject of this investigation is a new method for the construction of sulfonylated heterocycles which overcomes the limitations of classical approaches using a cheap feedstock sulfonylating agent, especially under photocatalyst- and metal-free conditions. [ABSTRACT FROM AUTHOR]

Sulfinates are important portals to various sulfonyl functional groups with wide applications and great societal impacts. The efficient synthesis of these versatile intermediates remains a key research topic in organosulfur chemistry. By employing Ni-electrocatalysis and SO2 as the sulfur source, our recent work on the room-temperature sulfinylation of a broad scope of readily available aryl iodides and electron-deficient bromides is presented. With the scalability of the e-sulfinylation demonstrated in both batch and flow settings, the practical use of SO2 stock solution is highlighted, and the preparation and titration of SO2 stock solution are detailed. [ABSTRACT FROM AUTHOR]

We herein report a method that enables the generation of glycosyl radicals under highly acidic conditions. Key to the success is the design and use of glycosyl sulfinates as radical precursors, which are bench‐stable solids and can be readily prepared from commercial starting materials. This development allows the installation of glycosyl units onto pyridine rings directly by the Minisci reaction. We further demonstrate the utility of this method in the late‐stage modification of complex drug molecules, including the anticancer agent camptothecin. Experimental studies provide insight into the reaction mechanism. [ABSTRACT FROM AUTHOR]

Sulfones and carboxylic acids are prominent motifs widely present in the chemical structure of agrochemicals, pharmaceuticals and many other highly valuable compounds. Herein, we describe a conjunctive strategy for the precise installation of these functionalities onto styrenes using sodium sulfinates and CO2 as coupling partners. The protocol allowed the preparation of carboxy‐sulfonylated compounds in good yields and broad functional group tolerance. Additionally, taking advantage of the leaving group ability of the sulfone moiety, a one‐pot photocatalytic carboxy‐sulfonylation‐elimination strategy was developed for the synthesis of α‐aryl‐acrylates. [ABSTRACT FROM AUTHOR]

The exploration of inexpensive and stable heterogeneous catalysts for C–S coupling reactions remains a challenging issue. Herein, we successfully prepared a new biomass-derived copper catalyst and applied it to the selective C(sp3)–H-directed sulfonylation of ketone hydrazones with commercial sodium sulfinates. The catalyst was characterized using different spectroscopic and microscopic techniques. Importantly, the prepared biomass-supported Cu catalyst catalyzed the C–S coupling reaction with considerably high activity. A variety of aryl and alkyl sulfinates were converted to the corresponding sulfones with good yields. In particular, the heterogeneous catalyst could be recovered easily after the synthesis and consecutively used at least five times with no appreciable decrease in the catalytic activity. Lastly, the copper catalyst is expected to have further applications in organic reactions catalyzed by Cu/CuO2. [ABSTRACT FROM AUTHOR]

A new direct sulfenylation method of indoles by sodium sulfinates and hydroiodic acid was developed giving variety of 3‐sulfenylindoles in high yields under mild conditions without using any catalysts or other additives. In situ‐generated RS‐I species are supposed to be mainly responsible for the key electrophilic alkyl‐ or aryl‐thiolation process. [ABSTRACT FROM AUTHOR]

An efficient nickel-catalyzed cross-coupling for the synthesis of 2-sulfonylthiazoles from readily available 2-chlorobenzothiazoles and sodium sulfinates has been developed. A variety of 2-chlorobenzothiazoles and sulfinates having a diverse range of substitution patterns can undergo the coupling process successfully at room temperature. Avoiding the use of precious catalysts and sensitive ligands, moderate to excellent yields of various 2-sulfonylthiazoles were observed. [ABSTRACT FROM AUTHOR]

An efficient and practical approach for the synthesis of triaryl allenyl sulfones from easily accessible propargylic alcohols was developed, by using sodium sulfinates as a sulfonyl source in the presence of Brønsted acid. The reaction proceeded via allenyl carbocation as the key intermediate and was followed by a nucleophilic attack of sodium sulfinates to produce allenyl sulfones in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-free. • C H functionalization. • Good functional group tolerance. • Multistep cascade reaction. The efficient synthesis of sulfonated naphthols was realized by dehydroaromatization of β-tetralones with sodium sulfinates under metal-free conditions. Iodine-containing reagents played an important role in this oxidative coupling process. Sodium sulfinates served as a stable and readily available sulfur source, providing sulfones in good to excellent yields. A wide range of functional groups were well tolerated in this reaction. [ABSTRACT FROM AUTHOR]

The functionalization of quinoxalinones is synthetically and biologically appealing, however, C2 functionalized quinoxalinones is not reported via environmentally friendly approach. Herein, we disclosed C2–O sulfonylation of quinoxalinones via our developed electrochemical oxidative O–S coupling strategy for synthesizing 2-sulfonyloxylated quinoxalines. Applying this protocol, quinoxalin-ones and sodium sulfinates as the starting materials, a wide range of 2-sulfonyloxyl quinoxaline derivatives were obtained in moderate to good yields with good functional-group tolerance under mild conditions without additional oxidants. The utility of this methodology and the sulfonyloxyl handles was demonstrated trough gram-scale preparation and the synthesis of 2-substituted quinoxaline-based bioactive molecules, respectively. [ABSTRACT FROM AUTHOR]

We have developed facile methods for synthesizing difluoroarenes and sodium aryldifluoromethyl sulfinates (ArCF2SO2Na) via Pd/C‐H2 and NaBH4 reduction of readily available aryldifluoromethyltriflones in excellent yields under mild conditions. Furthermore, we demonstrated that the obtained sodium aryldifluoromethyl sulfinates are excellent aryldifluoromethyl radical precursors. We have used the sodium aryldifluoromethyl sulfinates successfully in photocatalyzed radical addition‐cyclizations and Minisci‐type reactions. [ABSTRACT FROM AUTHOR]

The intermediate oxidation state of sulfoxides is central to the plethora of their applications in chemistry and medicine, yet it presents challenges for an efficient synthetic access, limiting the structural diversity of currently available sulfoxides. Here, we report a data‐guided development of direct decarboxylative sulfinylation that enables the previously inaccessible functional group interconversion of carboxylic acids to sulfoxides in a reaction with sulfinates. Given the broad availability of carboxylic acids and the growing synthetic potential of sulfinates, the direct decarboxylative sulfinylation is poised to improve the structural diversity of synthetically accessible sulfoxides. The reaction is facilitated by a kinetically favored sulfoxide formation from the intermediate sulfinyl sulfones, despite the strong thermodynamic preference for the sulfone formation, unveiling the previously unknown and chemoselective radicalophilic sulfinyl sulfone reactivity. [ABSTRACT FROM AUTHOR]

Sodium sulfinate addition to (E)‐β‐chlorovinyl ketones followed by the aerobic cycloisomerization of alkenyl sulfone intermediates has been established for the synthesis of 3‐sulfonyl furans. The optimal cycloisomerization catalyst system was identified to be Cu(OTf)2, where molecular oxygen acts as a terminal oxidant. With three points of structural variation in both β‐chlorovinyl ketones and sodium sulfinates, the current aerobic cycloisomerization strategy allows the synthesis of highly functionalized and substituted furan derivatives. [ABSTRACT FROM AUTHOR]

A simple and metal‐free perfluoroalkylation of 4‐quinolones have been developed using sodium perfluoroalkyl sulfinates and ammonium peroxodisulfate in DMSO under mild conditions. This transformation provides direct access to C‐3 perfluoroalkylated 4‐quinolones with broad functionality in satisfactory yields. The control experimental results suggest a radical mechanistic pathway was involved in this protocol. [ABSTRACT FROM AUTHOR]

Catalyst-free reactions employing renewable resources are needed for sustainable development. For example, biologically important β-keto sulfones have been recently synthesized by decarboxylative-coupling reaction between arylpropiolic acids and sulfonic acid derivatives. Nonetheless, existing protocols involve harsh conditions, complicated work-up, and the use of metal catalysts and extra oxidants. To address these shortcomings, we propose here catalyst-free decarboxylative oxysulfonylations of arylpropiolic acids employing air as a green oxidant. Arylpropiolic acids and sodium sulfinates are mixed in the hexafluoroisopropanol solvent under an aerobic atmosphere at room temperature. The results show that β-keto sulfones are formed in 60–97% yields. The products are purified by simple recrystallization. This method is also used to the direct synthesis of bioactive agents and the late-stage functionalization of an estrone derivative. [ABSTRACT FROM AUTHOR]

Herein, a novel visible-light photocatalytic radical addition–translocation–cyclization (RATC) approach for the efficient synthesis of sulfonyl-containing azacycles is described. The reaction delivers a wide range of monocyclic, bicyclic and polycyclic azacycles by using easily prepared sodium sulfinates and N-homopropargylic amines as starting materials. Instead of the traditionally used toxic tin reagents and thermally hazardous azos in the RATC process, clean, renewable and sustainable visible light combined with a catalytic amount of photosensitizer is used in this process. Moreover, the successful transformation of some drug derivatives further highlights the potential application of this procedure. [ABSTRACT FROM AUTHOR]

Simple access to aryl sulfinates from aryl iodides and bromides is reported using an inexpensive Ni‐electrocatalytic protocol. The reaction exhibits a broad scope, uses stock solution of simple SO2 as sulfur source, and can be scaled up in batch and recycle flow settings. The limitations of this reaction are clearly shown and put into context by benchmarking with state‐of‐the‐art Pd‐based methods. [ABSTRACT FROM AUTHOR]

Simple access to aryl sulfinates from aryl iodides and bromides is reported using an inexpensive Ni‐electrocatalytic protocol. The reaction exhibits a broad scope, uses stock solution of simple SO2 as sulfur source, and can be scaled up in batch and recycle flow settings. The limitations of this reaction are clearly shown and put into context by benchmarking with state‐of‐the‐art Pd‐based methods. [ABSTRACT FROM AUTHOR]