19377-04-9

A catalytic Lewis acid regulated reaction between quinone imine ketals (QIKs) and 1,3-dicarbonyl compounds provides a divergent and tunable approach to a variety of skeletons, including a series of 2-aryl-1,3-dicarbonyl compounds, indoles, and benzofurans. The use of lithium chloride and ferrous bromide gives C3- or C2-alkylation products of the QIKs. The combination of ferrous bromide and trifluoromethanesulfonic acid delivers indole derivatives. Sequential hydrolysis and C3-alkylation occur in the presence of ytterbium (III) trifluoromethanesulfonate and stoichiometric amounts of water. When the reaction is performed with trifluoromethanesulfonic acid and stoichiometric amounts of water, benzofuran is obtained. This protocol utilizes mild conditions, exhibits regio- and chemoselectivity, and has broad functional group tolerance. (Figure presented.).

A metal-free one-pot two-step synthesis of sulfonamides from readily available nitroarenes and sodium arylsulfinates in a mixture of methanol and water has been developed. In this procedure, the aryl amines were produced in situ by the reduction of nitroarenes mediated by diboronic acid, and then coupled with sodium arylsulfinates in the presence of iodine. A series of N-arylsulfonamides with various functional groups were obtained in moderate to good yields under the optimal reaction conditions. In addition, this one-pot process is applicable for gram-scale synthesis.

A metal-free reaction of nitrosoarenes, aryldiazonium tetrafluoroborates, and sulfur dioxide under mild conditions is developed, giving rise to sulfonamides in moderate to good yields. This transformation proceeds efficiently at room temperature in the presence of cyclohexa-1,4-diene with a broad reaction scope. Good functional group compatibility is observed, including cyano, halo, and ester. A plausible mechanism involving a radical process with the insertion of sulfur dioxide is proposed, and cyclohexa-1,4-diene serves as the reductant during the transformation.

Ferrocene tethered N-heterocyclic carbene-copper complex anchored on graphene ([GrFemImi]NHC@Cu complex) has been synthesized by covalent grafting of ferrocenyl ionic liquid in the matrix of graphene followed by metallation with copper (I) iodide. The [GrFemImi]NHC@Cu complex has been characterized by fourier transform infrared (FT-IR), fourier transform Raman (FT-Raman), CP-MAS 13C NMR spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) surface area analysis and X-ray diffractometer (XRD) analysis. This novel complex served as a robust heterogeneous catalyst for the synthesis of bioactive N-aryl sulfonamides from variety of aryl boronic acids and sulfonyl azides in ethanol by Chan-Lam coupling. Recyclability experiments were executed successfully for six consecutive runs.

An unexpected reaction between benzynes and isocyanates to generate aromatic amines has been developed under transition-metal-free conditions. The in situ prepared anions formed through cleavage of the N–C bond in isocyanates, reacted with aryne precursor

Differentiation of the isomeric haloanilines still remains a challenging and?necessary?analytic task due to their identical retention time in chromatography and similar mass spectra. In this work, p-tosylation of haloanilines by reaction of haloanilines with p-toluenesulfonyl chloride resulted in the corresponding N-tosyl haloanilines. Fragmentation of protonated N-tosyl haloanilines in electrospray ionization tandem mass spectrometry (ESI-MS/MS) mainly resulted in tosyl cation, haloaniline radical cation, and halohydroxyaniline radical cation. The MS/MS of the three group isomeric derivatives showed significant difference in abundance distribution of these product ions, respectively. Theoretical calculations showed that the stability of the ion-neutral complex (INC) is a key factor influencing the relative intensity of the product ions. The three group isomeric derivatives were also separated by high performance liquid chromatograph (HPLC) at conventional conditions. p-Tosylation combined tandem MS (or HPLC) technique were carried out to realize the differentiation of isomeric haloanilines.

A copper-catalyzed Chan-Lam-coupling-like reaction of a (het)arylboronic acid and chloramine-T (or a related compound) has been developed for the synthesis of N -arylsulfonamides at room temperature in moderate to good yields, with good tolerance of functional groups. In this process, it is believed that chloramine-T serves as an electrophile.

A green and practical method for the synthesis of N-arylsulfonamides from chloramine salts and arylboronic acids is herein developed. The reaction proceeds readily in the presence of 5 mol% of CuI and 2.5 equiv. K2CO3 in water at room temperature, generating a variety of N-arylsulfonamides in moderate to good yields with good functional group tolerance.

An expeditious protocol for amidation arylboronic acid has been developed using TsNBr2 as the nitrogen source in presence of a CuI as catalyst. Various arylboronic acids could be transformed into corresponding N-arylsulfonamide derivatives within a very short time using CuI as catalyst in presence of DBU at room temperature.

One-step, catalytic synthesis of N-arylsulfonamides via the construction of N-S bonds from the direct coupling of sodium arylsulfinates with nitroarenes was realized in the presence of FeCl2 and NaHSO3 under mild conditions. In this process, stable and readily available nitroarenes were used as nitrogen sources, and NaHSO3 acted as a reductant to provide N-arylsulfonamides in good to excellent yields. A broad range of functional groups were very well-tolerated in this reaction system. In addition, mechanistic studies indicated that the N-S bond might be generated through direct coupling of nitroarene with sodium arylsulfinate prior to the reduction of nitroarenes by NaHSO3. Accordingly, a reaction mechanism involving N-aryl-N-arenesulfonylhydroxylamine as an intermediate was proposed.

An efficient approach for palladium(II) acetate catalyzed allylic amination of homoallylic alcohols with various amines via sequential retro-allylation and amination was developed, which afforded the corresponding allylic amines in up to 98% yield.

The Ir-catalyzed mild C-H amidation of benzoic acids with sulfonyl azides was developed to give reactions with high efficiency and functional-group compatibility. Subsequent protodecarboxylation of ortho-amidated benzoic acid products afforded meta- or para-substituted (N-sulfonyl)aniline derivatives, the latter being inaccessible by other C-H functionalization approaches. The decarboxylation step was compatible with the amidation conditions, enabling a convenient one-pot, two-step process. Without a trace: Carboxylic acids are used as traceless directing groups in the Ir-catalyzed direct C-H amidation of arenes with sulfonyl azides under mild conditions. The tandem protodecarboxylation of the ortho-amidated benzoic acid products afforded meta- or para-substituted (N-sulfonyl)anilines, which are difficult to obtain by other C-H functionalization approaches.

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An efficient and mild method using a bimetallic MnF2/CuI catalyst at 60 °C in water was developed for the N-arylation of amides and sulfonamides with aryl halides. A variety of functionalized amides and sulfonamides were coupled with different substituted aryl halides to afford the corresponding N-arylated products in good to excellent yields (up to 97 %). An efficient method using a bimetallic MnF2/CuI catalyst in combination with trans-1,2-diaminocyclohexane as the ligand has been developed for the cross-coupling of benzamides and sulfonamides with differently substituted aryl iodides in water. The corresponding N-arylated products were obtained in good to excellent yields (up to 97 %) under the catalytic conditions. Copyright

An efficient and convenient protocol has been developed for the N-arylation of sulfonamides with differently substituted aryl iodides using ligand-free copper iodide to afford the arylated products in good to excellent yields (up to 91%). Georg Thieme Verlag Stuttgart.

The preparation of N-acylsulfonamides is described using primary amines, arylsulfonyl chlorides and acyl chlorides. Reaction of primary aryl amines with arylsulfonyl chlorides in the presence of NaHCO3 produced N-arylsulfonamides, which reacted in situ with benzoyl chloride furnishing the corresponding N-benzoyl-N-arylsulfonamides in 72-96% yields. Accordingly, 4-nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as acylating agents. All the reactions were carried out under solvent-free conditions at room temperature and the products were isolated after simple work-up in high yields and purity.

A high-throughput screen targeting the EP1 receptor identified non-acidic glycine sulfonamide derivative 2a with a pKi of 6.2. Analogue synthesis allowed a thorough investigation of the structure-activity relationship (SAR) and led to a 100-fold increase in recombinant potency.

(Equation Presented) This paper describes a novel method to synthesize a quinoline backbone by incorporating allenyl cations into a catalytic intramolecular Friedel-Crafts reaction. The initial products were isomerized and aromatized upon treatment with acid and base, respectively, to give quinolines. The basic concept also proved to be promising for 1-benzazepine, 1-benzazocine, or isoquinoline synthesis.