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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]

Chiral sulfones are recurrent motifs in pharmaceuticals and bioactive molecules. Although chemical methods have been developed to afford α‐ or β‐ chiral sulfones, these protocols rely heavily on the pre‐synthesis of structurally complicated starting materials and chiral metal complexes. Herein, we described a photoenzymatic approach for the radical‐mediated stereoselective hydrosulfonylation. Engineered variants of ene reductases provide efficient biocatalysts for this transformation, enabling to achieve a series of β‐chiral sulfonyl compounds with high yields (up to 92 %) and excellent e.r. values (up to 99 : 1). [ABSTRACT FROM AUTHOR]

Chiral sulfones are recurrent motifs in pharmaceuticals and bioactive molecules. Although chemical methods have been developed to afford α‐ or β‐ chiral sulfones, these protocols rely heavily on the pre‐synthesis of structurally complicated starting materials and chiral metal complexes. Herein, we described a photoenzymatic approach for the radical‐mediated stereoselective hydrosulfonylation. Engineered variants of ene reductases provide efficient biocatalysts for this transformation, enabling to achieve a series of β‐chiral sulfonyl compounds with high yields (up to 92 %) and excellent e.r. values (up to 99 : 1). [ABSTRACT FROM AUTHOR]

Aryl sulfones and aryl sulfonamides are of great importance in organic synthesis and medicinal chemistry. Although ortho‐C−H functionalization of aryl sulfonyl compounds has been extensively explored, the functionalization of remote meta‐ and para‐C−H bonds is very rare. Herein, we report a tunable meta‐ and para‐selective C−H borylation of aryl sulfonyl compounds enabled by computationally designed ligands and iridium catalyst. This method is capable of accommodating a broad range of substrates under mild reaction conditions. Gram‐scale preparation can be achieved with iridium catalyst loading as low as 0.1 mol%. As the introduced boronate group can be easily converted into many other groups, our method provides a general solution to installing functional groups at either meta‐ or para‐position of aryl sulfones and aryl sulfonamides with good to excellent selectivity. [ABSTRACT FROM AUTHOR]

Aryl sulfones and aryl sulfonamides are of great importance in organic synthesis and medicinal chemistry. Although ortho‐C−H functionalization of aryl sulfonyl compounds has been extensively explored, the functionalization of remote meta‐ and para‐C−H bonds is very rare. Herein, we report a tunable meta‐ and para‐selective C−H borylation of aryl sulfonyl compounds enabled by computationally designed ligands and iridium catalyst. This method is capable of accommodating a broad range of substrates under mild reaction conditions. Gram‐scale preparation can be achieved with iridium catalyst loading as low as 0.1 mol%. As the introduced boronate group can be easily converted into many other groups, our method provides a general solution to installing functional groups at either meta‐ or para‐position of aryl sulfones and aryl sulfonamides with good to excellent selectivity. [ABSTRACT FROM AUTHOR]

The Friedel‐Crafts sulfonylation for the synthesis of diaryl sulfones derivatives was achieved by using triflic acid (TfOH) as the acidic catalyst with aryl sulfonyl chlorides and arenes at elevated temperatures. Different sulfones could be synthesized with this method in good to excellent yield and with high selectivity. In contrast to the previous methodology reported for this sulfonylation, the catalyst and the excess of arene could be easily recovered and re‐used in further batches. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed cross-coupling of benzyl trimethylammonium triflates and sulfonyl hydrazides for the synthesis of various benzyl sulfones is reported. This novel protocol shows widespread functional group tolerance, leading to the desired sulfones in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

A water‐promoted synthesis methodology for constructing 3‐sulfone propionic acids from sulfonyl hydrazides and α, β‐unsaturated propionic acids with excellent yields were reported. The green synthesis methodology was promoted by water without any catalyst, ligand and organic solvent. The D2O control experiment sufficiently proved that the 2‐hydrogen atom of 3‐sulfone propionic acid come from water. Moreover, the 3‐sulfone propionic acid derivates could be directly purified by crystallization without column chromatography. [ABSTRACT FROM AUTHOR]

Sulfonyl fluorides are useful motifs for a wide range of applications in organic synthesis including sulfur (VI) fluoride exchange‐based "click chemistry." Herein, a visible‐light‐mediated synthesis of sulfonyl fluorides from arylazo sulfones is described. In the present study, K2S2O5 and N‐fluorobenzenesulfonimide (NFSI) were used as the sulfonyl source and fluorinating agent, respectively, for visible‐light‐mediated fluorosulfonylation of arylazo sulfones to prepare various sulfonyl fluorides in 60–85% yield. This protocol is a synthetic approach to provide useful sulfonyl fluoride structures at room temperature. [ABSTRACT FROM AUTHOR]

A copper-catalyzed radical cross-coupling of cyclobutanone oxime esters with sulfonyl hydrazides has been developed. The copper-based catalytic system proved crucial for cleavage of the C−C bond of cyclobutanone oximes and for selective C–S bond-formation involving persistent sulfonyl-metal radical intermediates. This protocol is distinguished by the low-cost catalytic system, which does not require ligand, base, or toxic cyanide salt, and by the use of readily accessible starting materials, as well as broad substrate scope, providing an efficient approach to various diversely substituted cyano-containing sulfones. [ABSTRACT FROM AUTHOR]

A titanium(III)‐catalyzed desulfonylation gives access to functionalized alkyl nitrile building blocks from α‐sulfonyl nitriles, circumventing traditional base‐mediated α‐alkylation conditions and strong single electron donors. The reaction tolerates numerous functional groups including free alcohols, esters, amides, and it can be applied also to the α‐desulfonylation of ketones. In addition, a one‐pot desulfonylative alkylation is demonstrated. Preliminary mechanistic studies indicate a catalyst‐dependent mechanism involving a homolytic C−S cleavage. [ABSTRACT FROM AUTHOR]

The previously developed stereoselective [3+2] cycloaddition between N‐tert‐butanesulfinyl ketimines and arynes has been extended to the synthesis of enantiopure [(2‐pyridyl)sulfonyl]difluoromethylated cyclic sulfoximines. The use of 2‐PySO2CF2 as the facilitating group offers new opportunities for the elaboration of the [3+2] cycloaddition products by virtue of the diverse relativity of 2‐pyridyl sulfones. [ABSTRACT FROM AUTHOR]

A highly enantio‐ and regioselective hydrosulfonylation of 1,3‐dienes with sulfonyl hydrazides has been realized by using a palladium catalyst containing a monodentate chiral spiro phosphoramidite ligand. The reaction provided an efficient approach to synthetically useful chiral allylic sulfones. Mechanistic studies suggest that the reaction proceeds through the formation of an allyl hydrazine intermediate and subsequent rearrangement to the chiral allylic sulfone product. The transformation of the allyl hydrazine intermediate to the product is the enantioselectivity‐determining step. [ABSTRACT FROM AUTHOR]

A highly enantio‐ and regioselective hydrosulfonylation of 1,3‐dienes with sulfonyl hydrazides has been realized by using a palladium catalyst containing a monodentate chiral spiro phosphoramidite ligand. The reaction provided an efficient approach to synthetically useful chiral allylic sulfones. Mechanistic studies suggest that the reaction proceeds through the formation of an allyl hydrazine intermediate and subsequent rearrangement to the chiral allylic sulfone product. The transformation of the allyl hydrazine intermediate to the product is the enantioselectivity‐determining step. [ABSTRACT FROM AUTHOR]

In recent years, our group has been committed to develop a series of novel spiro-molecules, i.e. carbonyl-containing spiro[fluorene-9,9′-phenanthren]− 10′-one, 5 H -spiro[benzo[2,1-b:3,4-b′]dithiophene-4,4′-cyclopenta[2,1-b:3,4-b′]dithiophen]− 5-one and sulfonyl-containing spiro[fluorene-9,9′-thioxanthene] 10',10'-dioxide, as these molecules have advantages of simple synthesis, low production cost, outstanding thermal stability, high charge mobility, etc. Several derivatives containing spiro[fluorene-9,9′-phenanthren]− 10′-one, 5 H -spiro[benzo[2,1-b:3,4-b′]dithiophene-4,4′-cyclopenta[2,1-b:3,4-b′]dithiophen]− 5-one and spiro[fluorene-9,9′-thioxanthene] 10',10'-dioxide as core moieties were applied in perovskite solar cells, dye-sensitized solar cells, organic light-emitting diodes. Four types of hole transporting materials, namely Yih- , MS- , YLC- and LY- series, were applied in perovskite solar cells, achieving power conversion efficiencies ranging from 16% to 21%. We introduced these spiro-structured moieties into photosensitizer RY- and YS- series in dye-sensitized solar cells as these spiro molecules are bulky in size, achieving power conversion efficiencies ranging from 7.19% to 8.66% (one sun) and 24.45–26.19% (dim light). Furthermore, aside from their application in perovskite technology, the bifunctional MS -series also serves as a host material for organic light-emitting diodes, attaining an impressive external quantum efficiency of 27.1% (used as the host for the PO-01 yellow emitter). [Display omitted] ● Spiro-based materials applied in PSCs, DSSCs, OLEDs. ● Novel spiro-HTM has a D-A-D structure and is cost-effective and simplifies the synthesis process. ● Spiro-based materials improved solubility, excellent charge mobility, and efficient stacking. [ABSTRACT FROM AUTHOR]

An efficient iodine-mediated coupling of cyclic amines with sulfonyl hydrazides is reported. This transformation opens a new route to the synthesis of vinyl sulfones derivatives, which is a common structural motif in natural products and pharmaceuticals. Tentative mechanistic studies suggest that this reaction is likely to involve a radical process. [ABSTRACT FROM AUTHOR]

Oxidative coupling methodology is widely applied for the formation of carbon‐carbon and carbon‐heteroatom bonds. This review focuses on methods for oxidative sulfonylation of multiple bonds involving sulfonyl hydrazides, sulfinic acids and their salts as sulfonylation reagents. Under oxidative conditions, they generate sulfonyl radicals, trapped by multiple carbon‐carbon bonds resulting in a variety of SO2‐containing products: mainly, vinyl and alkynyl sulfones, hydroxy‐, keto, and halo‐substituted sulfones, sulfonylated derivatives of carbo‐ and heterocycles. This exhaustive review summarizes 321 references from 1996 to 2020 with the specialization of the studies of the last five years, and is divided into the chapters according to the classes of compounds being sulfonylated. [ABSTRACT FROM AUTHOR]

p‐tosylmethyl isocyanide (TosMIC) which is also known as van Leusen's reagent hold the three functionalized groups including the isocyanide and sulfonyl group and an alpha carbon which is acidic by nature. Tosyl set of this fortunate reagent acts as a good leaving group and assist the alpha carbon to contribute in a range of cyclization strategies. Exceptionally, TosMIC was also proved as a good sulfonylating and sulfomethylating reagent. TosMIC has proved as a powerful and versatile synthon and betrothed in the synthesis of broad range of heterocycles having pharmacological interest. This review is focused on synthetic utility of TosMIC in diverse range of heterocycles like five membered heterocycles, fused heterocycles, linked or tethered heterocycles, spiro compounds etc. It is also utilized for regio, chemo and stereoselective synthesis and production of sulfones and sulfinates. It serves as an important building block in various synthetic methodologies like multi component reaction, cyclization, domino, cascade and cycloaddition and metal catalysed reactions. Various new catalyst and novel methodologies were explored due to enormous use of this wonderful reagent. [ABSTRACT FROM AUTHOR]

Herein, an electrochemical oxidative cross‐coupling reaction between terminal alkynes and sulfonylhydrazides has been developed. Tetrabutylammonium iodide is used as the electrolyte and redox medium. The significant advantages of this method are high atom efficiency, functional group tolerance, and transition metal‐ and oxidant‐free conditions. Most of the compounds exhibit good inhibitory activity on tumor cell lines, and one of the compounds can inhibit cell migration and induce apoptosis in HeLa cells. [ABSTRACT FROM AUTHOR]

The synthesis of vinyl sulfones via silver-promoted cross-coupling of vinyl bromides with sulfonyl hydrazides was realized. Water was used as the sole solvent. Multisubstituted vinyl sulfones were easily prepared with excellent alkyl group tolerance. A mechanism involving nucleophilic attack of a sulfinate anion was proposed. [ABSTRACT FROM AUTHOR]

Highly regioselective synthetic methodology leading to densely functionalised C(3), C(4) and C(5) substituted pyrazoles 10a–q, 14a‐i and 16a–g via thermal [3+2]‐dipolar cycloaddition, of α‐diazoacetates and α‐thio‐β‐chloroacrylamides, at the sulfide, sulfoxide and sulfone levels of oxidation, is described. This method allows access to C(4)‐sulfenyl or sulfonyl pyrazoles, through migration of the sulfur substituent at the sulfide and sulfone oxidation levels, while elimination of the sulfinyl group leading to 3,5‐disubstituted pyrazoles, is observed. While the sulfide migration is readily rationalised, the carbon to carbon 1,2‐sulfonyl migration is unprecedented and mechanistically intriguing. The synthetically versatile generation of densely functionalised pyrazoles containing substituents amenable to further modification offers advantages over alternative synthetic routes. Isolation of the N‐alkylated pyrazoles 11a and 12a as by‐products from the cycloaddition through further reaction of the pyrazoles 10 with excess α‐diazoacetate, proved useful in rationalising the tautomeric behaviour evident in the NMR spectra of the pyrazoles, with the position of tautomeric equilibrium influenced by solvent and substituents. [ABSTRACT FROM AUTHOR]

We report the application of the click Michael‐type addition reaction to vinyl sulfone or vinyl sulfonate groups in the synthesis of rotaxanes through the threading‐and‐capping method. This methodology has proven to be efficient and versatile as it allowed the preparation of rotaxanes using template approaches based on different noncovalent interactions (i.e. donor‐acceptor π–π interactions or hydrogen bonding) in yields of generally 60–80 % and up to 91 % aided by the mild conditions required (room temperature or 0 °C and a mild base such as Et3N or 4‐(N,N‐dimethylamino)pyridine (DMAP)). Furthermore, the use of vinyl sulfonate moieties, which are suitable motifs for coupling‐and‐decoupling (CAD) chemistry, implies another advantage because it allows the controlled chemical disassembly of the rotaxanes into their components through nucleophilic substitution of the sulfonates resulting from the capping step with a thiol under mild conditions (Cs2CO3 and room temperature). [ABSTRACT FROM AUTHOR]

5-Aminopyrido[3′,2′:4,5]thieno[3,2-c]isoquinolines were synthesized via alkylation of 3-cyanopyridine-2(1H)-thiones with 2-(chloromethyl)benzonitrile followed by treatment of the products with potassium tert-butoxide. The oxidation of the alkylated products to corresponding sulfoxides or sulfones followed by treatment with potassium tert-butoxide provided the corresponding 11-oxides or 11,11-dioxides. [ABSTRACT FROM AUTHOR]

Sulfonylated pyridines were synthesized in moderate to excellent yields, with a wide scope of substituted pyridines and sulfinate salts as starting materials, by an iron-catalyzed SNAr reaction. This new methodology exhibits advantages for the synthesis of these useful substrates, such as the use of a readily available, inexpensive catalyst, prevention of the disproportionation of the sulfinate salts, and, more importantly, providing access to electron-rich pyridine substr [ABSTRACT FROM AUTHOR]

An efficient palladium-catalyzed cascade reaction of azides with isonitrile and amines is presented; it offers an alternative facile approach toward N-sulfonyl-, N-phosphoryl-, and N-acyl-functionalized guanidines in excellent yield. These series of substituted guanidines exhibit potential biological and pharmacological activities. In addition, the less reactive intermediate benzoyl carbodiimide could be isolated by silica gel column flash chromatography in moderate yield. [ABSTRACT FROM AUTHOR]

This study describes the reduction of 4-methyl- and 4-phenyl-3-(methylsulfonyl)pyrazolo[5,1- c][1,2,4]triazines and 3-[(4-methylphenyl)sulfonyl]pyrazolo[5,1- c][1,2,4]triazines, which were obtained by reactions of pyrazole-3(5)-diazonium salts with the appropriate β-ketosulfones. The interaction of sulfonyl derivatives of pyrazolo[5,1- c][1,2,4]triazines with sodium dithionite or thiourea 1,1-dioxide under mild conditions resulted in chemospecific partial reduction of the as-triazine ring. The configuration of the obtained pyrazolo[5,1- c][1,2,4]triazine dihydro derivatives was established by X-ray structural analysis. [ABSTRACT FROM AUTHOR]

A novel and convenient method has been developed for the 1,2-selenosulfonylation of alkynes under metal-free conditions. The reaction avoids the need for the pre-prepared Se–S reagents, providing facile access to a series of β-(seleno)vinyl sulfones with high levels of regio- and stereoselectivity. The key features of this reaction include broad substrate scope, excellent functional-group tolerance, readily available reagents and amenability to gram-scale synthesis. Preliminary mechanistic studies support the proposed cationic-species-induced pathway. [ABSTRACT FROM AUTHOR]

An efficient Ag2CO3-promoted sulfonylation of allyl/propargyl alcohols with sodium sulfinates has been developed. The reaction tolerates a wide range of functional groups to deliver γ-keto sulfones in high yields (up to 93 %). Propargyl alcohols furnished trimerization product 1,3,5-triaroylbenzenes in the presence of sodium methanesulfinate under the standard conditions. A mechanism involving a sulfonyl radical was suggested. [ABSTRACT FROM AUTHOR]

Sodium amalgam mediated desulfonylative reduction of β-ketosulfones in MeOH at rt affords alcohols in good yields via radical desulfonylation of β-ketosulfones and sequential Bouveault-Blanc reduction of the resulting ketones. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • We have developed a novel C sp 3 S bond formation by oxidative C sp 2 C sp 2 bond cleavage in one step. • This protocol provided a new route to various functionalized β -keto-sulfones in moderate to good yields. • The compound was synthesized from readily available N , N -dimethylenaminones and arylsulfonyl hydrazides. Abstract A novel TBAI-catalyzed radical sulfonylation of readily available N , N -dimethylenaminones with sulfonylhydrazides to afford functionalized β-keto-sulfones has been developed. Various functional groups were tolerated well under the present oxidative conditions and the corresponding β-keto-sulfone compounds were obtained in moderate to good yields. Importantly, this transformation offered the first protocol for Csp3 S bond formation by oxidative Csp2 Csp2 bond cleavage in one step. [ABSTRACT FROM AUTHOR]

A simple and mild copper-catalyzed sulfonylation of 8-aminoquinolines with sodium and lithium sulfinates is reported. In the presence of manganese(III) acetate [Mn(OAc)3] as cooxidant a highly site-selective C−H functionalization at the C-5 position takes place. The reaction proceeds readily at room temperature in air and various sulfones were synthesized in moderate to high yields. Moreover, a straightforward procedure for the conversion of organolithium reagents and sulfur dioxide into C-5 sulfonylated quinolines was developed. [ABSTRACT FROM AUTHOR]

Reported herein is the first enantioselective β-elimination reaction catalyzed by a chiral cation-binding polyether. By using this catalytic protocol, a wide range of β-sulfonyl ketones could be effectively resolved with high stereoselectivity (S up to >300). Key to the success of this process is the favorable secondary interactions of the catalyst with the Lewis basic groups on the sulfone substrate. The enone product of this process can be easily converted into the racemic starting material, and allows an effective recycling and overall synthesis of chiral β-sulfonyl ketones in high yield and excellent enantioselectivity. [ABSTRACT FROM AUTHOR]

The phenylsulfonylethylidene (PSE) acetal is a relatively new protecting group in carbohydrate chemistry. However, carbohydrate-derived phenylsulfonylethylidene (PSE) acetals show a different behavior in reductive desulfonylation than simple symmetrical acetals. Here we have investigated various SET-type reaction conditions in order to open PSE acetals regioselectively and to produce chiral ω-hydroxyethenyl ethers. Whereas sodium amalgam leads to a mixture of regioisomeric vinyl ethers besides the ethylidene acetal, samarium iodide is suited for regioselective ring opening. This is shown with seven different carbohydrate PSE acetals, both of the 1,3-dioxane and the 1,3-dioxolane type. [ABSTRACT FROM AUTHOR]

A new TBHP/TBAI-mediated reaction of propargyl alcohols with sulfonyl hydrazides in the presence of HOAc has been established, in which a wide variety of allenyl sulfones were obtained in moderate to excellent yields. Mechanistic studies indicate that this transformation involves HOAc-promoted sulfonohydrazide intermediate formation, sequential C-O, C-N, and N-S bond cleavage, and C-S bond formation. Significantly, this sulfonohylation proceeds in a radical process and shows highly functional group compatibility and excellent regioselectivity, with a short reaction time and inexpensive reagents. [ABSTRACT FROM AUTHOR]

The first organocatalytic synthesis of cis-decalins using sulfonyl Nazarov reagents is reported. The Jørgensen's catalyst directs this highly enantioselective synthesis using different cyclohexenal derivatives. [ABSTRACT FROM AUTHOR]

Several chiral sulfonyl compounds were prepared using the iridium catalyzed asymmetric hydrogenation reaction. Vinylic, allylic and homoallylic sulfone substitutions were investigated, and high enantioselectivity is maintained regardless of the location of the olefin with respect to the sulfone. Impressive stereoselectivity was obtained for dialkyl substitutions, which typically are challenging substrates in the hydrogenation. As expected, the more bulky Z-substrates were hydrogenated slower than the corresponding E isomers, and in slightly lower enantioselectivity. [ABSTRACT FROM AUTHOR]

We report a double-addition reaction of methyl phenyl sulfone and methyl 2-pyridyl sulfone with N- tert-butylsulfinyl imines. This method provides concise access to 2-sulfonylated 1,3- anti diamines with good to excellent diastereoselectivities. This protocol has the benefit of using readily accessible starting materials and is operationally simple. [ABSTRACT FROM AUTHOR]

An efficient, AgNO3/K2S2O8 catalyzed one-pot radical route to β-keto sulfones from alkenes is reported. The protocol involves oxysulfonylation of alkenes with air (O2) and inexpensive sodium arenesulfinate salts under mild conditions. It is highly practical and allows the use of easily available starting materials in an open flask and aqueous medium at ambient temperature. [ABSTRACT FROM AUTHOR]

Chloroaluminate ionic liquid bound on magnetic nanoparticles (Fe3O4@O2Si[PrMIM]Cl·AlCl3) was prepared and used as a heterogenous Lewis acidic catalyst for the Friedel–Crafts sulfonylation of aromatic compounds with sulfonyl chlorides or p-toluenesulfonic anhydride. The catalyst's stability, efficiency, easy recovery, and high recyclability without considerable loss of catalytic capability after four recycles were evidence of its advantages. Furthermore, the stoichiometry, wide substrate scope, short reaction time, high yield of sulfones, and solvent-free reaction condition also made this procedure practical, ecofriendly, and economical. [ABSTRACT FROM AUTHOR]

Abstract: The Hayashi–Jørgensen organocatalyst has made possible a sulfonyl Nazarov analogue reagent to give a Diels–Alder reaction at the double bond, without involving the activated methylene affording chiral highly functionalised cyclohexa-1,3-dienes. [Copyright &y& Elsevier]

The reaction of arylsulfones 11a–d with hydrazonoyl chloride derivative 13 furnished celecoxib analogs 4-(3-acetyl-5-aryl-4-(arylsulfonyl)-1H-pyrazol-1-yl)benzenesulfonamides 15a–d, respectively. Oximes 16a, b and hydrazones 17a, b were prepared by reacting sulfones 11a, b with hydroxyl amine and phenyl hydrazine, respectively. The anti-inflammatory activity of the synthesized compounds showed that, 5-(4-bromophenyl)-4-(phenylsulfonyl)pyrazole 15c and 5-(4-bromophenyl)-4-(4-tolylsulfonyl)pyrazole 15d exhibited excellent anti-inflammatory activity with ED50 = 68 ± 2.2 and 51 ± 0.7 μM/kg, respectively, higher than that of celecoxib (ED50 = 86 ± 1.1 μM/kg) after 3 h with acceptable ulcer index. In addition, the LD50 of 15c and 15d is 7.1 mM/kg for each, and 9.8 mM/kg for celecoxib. Compound 15d appeared selectivity index (COX-2/COX-1) almost the half of celecoxib while 15c is non-selective for COX-2. Compound 15c with ED50 = 80 ± 2.8 μM/kg showed a significant analgesic activity when compared with celecoxib (ED50 = 70 ± 3.9 μM/kg) after 2 h whereas 15b (ED50 = 50 ± 1.2 μM/kg) and 15d (ED50 = 69 ± 2.7 μM/kg) seemed to be more potent than celecoxib (ED50 = 156 ± 4.8 μM/kg) but with a shorter duration (0.5 h). [ABSTRACT FROM AUTHOR]

Inthe course of a study of the alkoxyallylation of allenic sulfonesthrough the use of π-allylpalladium chemistry, we discoveredan isomerization of allenic sulfones to arylsulfonyl 1,3-dienes. Underconditions of palladium catalysis in the presence of acids such asacetic acid, allenic sulfones are converted to 1-arylsulfonyl 1,3-dienes.On the other hand, nucleophilic catalysis using triphenylphosphinein the presence of a proton shuttle yields 2-arylsulfonyl 1,3-dienes.Thus, either regioisomer of the arylsulfonyl diene can be preparedat will based on changes in reaction conditions. [ABSTRACT FROM AUTHOR]

An efficient, concise, and transition metal-free synthesis of functionalized sulfonylated five-membered heterocyclic compounds via an SNAr reaction has been developed. Using commercially available sodium sulfinates as sulfonylation reagents, various five-membered heterocyclic sulfones were obtained in good yields [ABSTRACT FROM AUTHOR]

Abstract: A facile one-step synthetic protocol toward multifunctionalized m-terphenyls 5 and sulfonyl m-terphenyls 6 is developed from substituted chalcones 1 and allyl sulfone 2 in good yields via a [3C+3C] annulation. The NaH-mediated annulation features transition metal catalyst-free condition. Chalcones 1 with the functional groups tolerance are easily prepared via Claisen–Schmidt condensation of substituted benzaldehydes 3 with acetophenone 4 in a qualitative yield under an aqueous alkaline methanolic solution. [Copyright &y& Elsevier]

[Display omitted] A mild, practical, eco-friendly and environmentally friendly electrochemical synthesis method of β-aminovinyl sulfone and carbonyl sulfones from sulfonyl hydrazide and enamides has been developed. This transformation only requires electrolytes and solvent, thus avoids transition metal catalysts, stoichiometric oxidant and base. Two different types of sulfone derivatives can be obtained only by changing the reaction solvent. This transformation also features mild conditions (room temperature, air), broad substrate scopes, and excellent stereoselectivities in mild to good yield. [ABSTRACT FROM AUTHOR]

[Display omitted] A new synthesis of diaryl sulfones is achieved from N,N' -disulfonylhydrazines and diaryliodonium salts. Its key advantage is that N,N' -disulfonylhydrazines carry out an efficient base-promoted evolution of nitrogen to generate in situ ammonium sulfinates with good solubility and high reactivity. N,N' -Disulfonylhydrazines prove to be an excellent synthetic equivalent of sulfinic acids and their salts with none of their drawbacks. [ABSTRACT FROM AUTHOR]

Metabolism of pyroxasulfone in a tolerant crop, wheat and a susceptible plant, rigid ryegrass, was studied using 14C-pyroxasulfone. The main metabolites were a cysteine conjugate of the isoxazoline ring (M-26), deaminated M-26 (M-29) and a glucose conjugate of M-29, suggesting that the main metabolic route in both plants was the cleavage of the methylenesulfonyl linkage caused by glutathione conjugation. The difference in the metabolic activity was assumed to be one of the factors in determining the selectivity of pyroxasulfone between wheat and rigid ryegrass. [ABSTRACT FROM AUTHOR]

The paths of nucleophilic fluoroalkylation reaction of propylene oxide with PhSO2CYF- (Y = F, H, and PhSO2, respectively) in the gas phase and in Et2O solvent were studied theoretically. The nucleophilic fluoroalkyl- ation of propylene oxide with fluorinated carbanions was probed by compa- rison of the reactivities (phenylsulfonyl)monofluoromethyl anion (PhSO2CHF-), the (phenylsulfonyl)difluoromethyl anion (PhSO2CF2-), and the bis(phenylsul- fonyl)monofluoromethyl anion ((PhSO2)2CF- ). The nucleophilicity reactivity order of PhSO2CYF- (Y = F, H, and PhSO2) is (PhSO2)2CF- > PhSO2CHF- > > PhSO2CF2-, which indicates that the introduction of another electron-withdrawing phenylsulfonyl group is an effective way to significantly increase the nucleophilicity of fluorinated carbanions. For comparison, the nucleophilic addition reaction of propylene oxide with the chlorine-substituted carbanion PhSO2CHCl- was investigated. The calculated results show that the nucleophilicity of PhSO2CYF- is better than that of PhSO2CHCl- in the ring opening reaction with propylene oxide. The calculated results are in good agreement with the available experimental ones. [ABSTRACT FROM AUTHOR]

Abstract: The asymmetric C–H insertion of alkyldiazosulfones has been studied. High selectivity was achieved using a combination of a chiral catalyst and a chiral auxiliary (Rh2(S-pttl)4 and menthyl ester). [Copyright &y& Elsevier]