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Abstract Regioselective hydroxysulfenylation of unactivated C C double bonds was reported. Using FeBr 3 -bpy as the catalyst, Na 2 S 2 O 8 as the oxidant, and sulfonyl hydrazides as the sulfenyl sources, hydroxysulfenylation of unfunctionalized olefins proceeded readily, giving a variety of β-hydroxysulfides in moderate to good isolated yields. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract A highly reactive intermediate N- sulfonyl acetylketenimine was generated from an ynone-participated CuAAC/ring-opening method. Its unique structure allowed it to react with aryl carboxylic acids to give N -aroylsulfonamides via a novel Mumm-type rearrangement. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

An efficient and convenient aryl sulfonyl introducing strategy for the synthesis of 3-sulfonyl coumarins via ipso -cyclization/1,2-ester migration from substituted phenyl 3-phenylpropiolates with disulfides and potassium persulfate as sulfonylating reagents was developed, halogen and many other electron-withdrawing or -donating functional groups are tolerated. When naphthalen-1-yl 3-phenylpropiolate was used as a starting material, a spiro compound was obtained via ipso -cyclization. [ABSTRACT FROM AUTHOR]

One-pot three-step sulfonylative alkoxyhydroxylation of 2-arylpropenes 1 affords oxygenated sulfonylcumenes 4 in moderate yields via a sequential route: (i) NBS-mediated allylic bromination of 2-arylpropenes 1 in CH 2 Cl 2 , (ii) sodium sulfinates 2 -promoted nucleophilic substitution of the resulting styryl bromides in a co-solvent of alcohol and water, and (iii) V 2 O 5 /H 2 O 2 mediated alkoxyhydroxylation of corresponding styryl sulfones 3 in alcohol. The synthetic route provides a highly effective protocol for the 1,2,3-tricarbofunctionalization of 2-arylpropenes 1 via two carbon-oxygen and one carbon-sulfur bond formations. [ABSTRACT FROM AUTHOR]

2-Carboxylated aza-rings have been synthesized in two steps through a highly selective monohalogenation of N -sulfonylated lactams of various ring sizes (from 5- to 8-membered rings) followed by a ring contraction reaction. The selective monohalogenation of N -sulfonyl lactams has been achieved in modest to excellent yields (9 examples, 39–96%) using N -halogenosuccinimides via the in situ generation of trimethylsilyl ketene aminal derivatives. The so-obtained α-halogeno N -sulfonyl lactams were engaged in a ring opening/ring closing reaction in the presence of various alcohols or anilines under basic conditions affording 2-carboxylated aza-rings, such as azetidine, pyrrolidine or piperidine derivatives in high yields (24 examples, 61–99%). [ABSTRACT FROM AUTHOR]

CuI mediated one-pot (3+2) annulation of β-ketosulfones 2 with styryl alcohol 3 in DMSO affords sulfonyl dihydrofurans 4 in good to excellent yields via a sequential intermolecular α-styrylation followed by intramolecular iodoetherification. The styrylative iodocyclization route provides a highly effective condition. A plausible mechanism has been studied and proposed. [ABSTRACT FROM AUTHOR]

The domino reactions of 2-fluoro benzensulfonyl acetonitrile and α-chloro oximes in the presence of Cs 2 CO 3 in aprotic high boiling point solvents have been achieved to provide isoxazole−fused 4 H -1,4-benzothiazine-4,4-dioxides via an unprecedented transition metal-free one-pot addition/cyclization process. The tunable synthesis of either isoxozolo-1,4-benzothiazin-4-oxides or their precursor 5-aminoisoxazoles can be controlled depending on the solvent selection. The observed products were characterized by means of (IR, 1 H, 13 C NMR and HRMS) and physical methods. [ABSTRACT FROM AUTHOR]

A concise and direct one-pot [4 + 1] synthetic strategy for the construction of 2-substituted benzazoles such as benzoxazoles and benzothiazoles has been disclosed in high yields (80–98%) by cascade coupling reaction of 2-amino(thio)phenols with β-oxodithioesters. The current approach enables N H/O H/S H functionalization in one-pot under solventless condition leading to diverse benzazoles without use of any external metal. A wide range of 2-amino(thio)phenols and β-oxodithioesters are compatible toward this transformation with excellent functional group tolerance. Furthermore, we preempt the wider implications of this novel strategy by demonstrating its compatibility toward versatile diversification of DNA Topoisomerase-II inhibitors. [ABSTRACT FROM AUTHOR]

A facile route to the synthesis of γ-sulfonyl lactones 5 and β-sulfonyl styrenes 6 has been developed, achieving moderate to good yields via the (1) NaH mediated Michael addition of β-ketosulfones 3 and methyl acrylate in refluxing THF and (2) NaBH 4 mediated stereoselective reduction/lactonization of δ-ketoesters 4 in boiling MeOH, or (3) boron trifluoride etherate mediated ring-opening of lactones 5 in MeOH at reflux. [ABSTRACT FROM AUTHOR]

Water-promoted sulfonylation of propargyl esters leading to highly regioselective and stereoselective formation of ( Z )-β-sulfonyl enoates in excellent yields, by a simple, mild, and environmentally benign reaction procedure without employing any ligand or additive is reported. [ABSTRACT FROM AUTHOR]

The conjugated bis(sulfonyl)nitrobutadienes 1 undergo, with primary amines, competitive MeSO 2 replacement [vinylic substitution at C(1)] versus aza-Michael addition to the nitroethenyl C(3)–C(4) double bond. The latter pathway eventually leads to the trisubstituted pyrroles 2 and conditions have been optimized in order to maximize the yield of such polyfunctionalized heterocycles. Interestingly, in trifluoroethanol tetrasubstituted pyrroles 7 are also formed, thanks to a final aromatization via oxidation by ‘endogenous’ nitrite. [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]

Tin triflate-promoted one-pot intramolecular annulation of α-geranyl or α-farnesyl β-ketosulfones 3 – 4 affords the respective bicyclic or tricyclic sulfonyl dihydropyrans 5 – 6 in moderate to good yields via a cascade cation-olefin-carbonyl carbocyclization process. The starting materials 3 and 4 were obtained by K 2 CO 3 -mediated α-geranylation or α-farnesylation of β-ketosulfones 1 with bromides 2a or 2b . The structures of the key products were confirmed by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Reactive acyl trifluoromethanesulfonates are formed from the reaction of acyl fluorides with trimethylsilyl trifluoromethanesulfonate (TMSOTf). These electrophiles undergo Friedel-Crafts reactions with electron-rich aromatics at room temperature. When a sulfur atom is present at their γ position, their cyclization to acylsulfonium cations is observed and is followed by a rearrangement leading to benzothiepinones (or dibenzo[b,e]thiepinones) in 40-85% yield. [ABSTRACT FROM AUTHOR]

We have developed an efficient one-pot reaction for the synthesis of 2,4-dihydroxy-6-phenylethylenyl-8-deazapteridine derivatives using 2,4-dihydroxy-6-methylpyrido[3,2- d ]pyrimidine, aromatic aldehydes and p -toluenesulfonamide through C(sp 3 )–H bond functionalization. This method is easy to operate and high-yielding, which is potentially useful for diversity-oriented synthesis. [ABSTRACT FROM AUTHOR]

A direct and highly stereoselective approach for the synthesis of Z -alkenyl-pyranoindoles had been developed by utilizing Rh(II)-catalyzed intramolecular cyclization of N -sulfonyl-1,2,3-triazoles with indole derivatives. A variety of pyranoindoles were obtained in 44–93% yields. Moreover, a more convenient synthesis of pyranoindoles starting from terminal alkyne was realized via a Cu–Rh sequentially catalyzed one-pot cascade reaction. [ABSTRACT FROM AUTHOR]

Oxidative radical cyclization of N -sulfonyl β-enamino esters with alkenes has been developed. Substituted 2,3-dihydropyrroles were produced when the reactions were carried out in the presence of CAN and Cu(OAc) 2 as the oxidant. Intramolecular cyclization of β-enamino carbonyl compounds having an alkenyl and an alkynyl side chain proceeded to afford the corresponding bicyclic products, respectively. [ABSTRACT FROM AUTHOR]

Fe(OTf) 3 -mediated one-pot (3+3) cycloaddition of β-ketosulfones 1 with prenyl alcohol ( 2 ) in MeNO 2 affords sulfonyl dihydropyrans 5 in good yields via a sequential intermolecular α-prenylation followed by intramolecular Friedel–Crafts alkylation. The method provides a highly effective condition. [ABSTRACT FROM AUTHOR]

Michael addition of hetero-nucleophiles to active vinylogous imine intermediates generated in situ from 3-(1-arylsulfonylalkyl)-7-azaindoles has been described. This new strategy provides a facile and efficient approach to valuable 3-alkyl substituted 7-azaindole derivatives containing heteroatoms in high yields. [ABSTRACT FROM AUTHOR]

Novel ribonucleoside 3′,5′-cyclic monophosphorodithioates were synthesized by a combination of the phosphoramidite and phosphotriester methods. These include uridine 3′,5′-cyclic monophosphorodithioate ( c UMPS 2 ), cytidine 3′,5′-cyclic monophosphorodithioate ( c CMPS 2 ), and guanosine 3′,5′-cyclic monophosphorodithioate ( c GMPS 2 ). In addition, 2,6-diaminopurine ribonucleoside 3′,5′-cyclic monophosphorodithioate ( c DAPMPS 2 ) was synthesized via the O 6 -amination reaction of the O 6 -sulfonylated guanosine derivative. [ABSTRACT FROM AUTHOR]

A stereoselective synthesis of sulfonyl tetrahydropyrans (THPs) 6 was performed with moderate to good yields by m -CPBA ( m -chloroperoxybenzoic acid)-mediated ring-closure of β-hydroxy sulfones 5 . Skeleton 5 is prepared by cinnamylation of β-ketosulfones 3 in the presence of K 2 CO 3 followed by NaBH 4 -mediated reduction of the resulting skeleton 4 with a α-cinnamyl side arm in the co-solvent of THF and MeOH. The key structures of skeleton 6 were confirmed by X-ray crystallographic analysis. The reaction mechanism had been discussed. [ABSTRACT FROM AUTHOR]

Abstract: Isomeric six- and five-membered (N2)-aromatics, 6-methylpyridazines and 5-vinylpyrazoles, which energetic topological aromaticity is comparable to that of benzene, are shown to be efficiently produced by sequential isomerization–elimination processes from the corresponding 6-methylidene-1,4,5,6-tetrahydropyridazines and 5-vinylpyrazolines, respectively. The latter precursors are available from the same N-sulfonyl,C-homoallyl-hydrazone substrates by a suitable choice of previously reported conditions for Pd-catalyzed CH-oxidative C,N-ring closing processes. The generality of these cyclization, isomerization, and aromatization reactions, for which detailed mechanisms are proposed, provides a systematic access to wide ranges of 3,4,6-trisubstituted 6-methyl-1,4-dihydropyridazines and 6-methylpyridazines, and their 3,4,5-trisubstituted 5-vinylpyrazole isomers. [Copyright &y& Elsevier]

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]

Abstract: The present work describes a new protocol for the synthesis of 5-aminoisoxazoles using α-chlorooximes and 2-phenylsulfonyl acetonitrile via green chemistry routes. The titled 5-aminoisoxazoles 3 were further reacted with 4-nitrobenzoyl chloride to obtain 5-amidoisoxazoles with moderate yields. These heterocyclic compounds were tested in vitro MTT study to investigate inhibitive abilities to some cancer cell lines (C3a, L929, T98g and Mcf-7) and compounds 3a, 3c, 3e and 3h showed noticeable cytotoxic property against four cancer cell lines. [Copyright &y& Elsevier]

Abstract: The reaction of aromatic or benzylic disulfides with 2.5 equiv of Selectfluor™ in acetonitrile/water (10:1) at room temperature efficiently produced the corresponding thiosulfonates. Conversely, the reaction of disulfides with 6.5 equiv of Selectfluor™ or thiosulfonates with 4.5 equiv of Selectfluor™ in refluxing acetonitrile/water (10:1) provided sulfonyl fluorides in high yields. Accufluor™ and FP-T300™ are also effective in preparing sulfonyl fluorides from disulfides under the similar reaction conditions. Sulfonyl chlorides or sulfonyl bromides were effectively obtained from the reaction of disulfides with 6 equiv of either N-chlorosuccinimide or N-bromosuccinimide in acetonitrile/water (10:1) at room temperature. Some other electrophilic chlorinating or brominating reagents are also able to be used instead of N-chlorosuccinimide or N-bromosuccinimide for the syntheses of sulfonyl halides from disulfides. These reactions of disulfides with electrophilic halogenating reagents are convenient methods to prepare thiosulfonates and sulfonyl halides. [Copyright &y& Elsevier]

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]

Abstract: The reactivity of a series of 1,5-disubstituted sulfonyl-triazoles was explored using either thermolytic or metal-catalyzed conditions. Both the thermolysis and the Rh(II)-catalyzed reactions led to the synthesis of α-sulfonyl-nitriles, which presumably occurred through a carbene or carbenoid mechanism. The reactivity of the carbenes and carbenoids resulting from the loss of dinitrogen from the 1,5-disubstituted sulfonyl-triazoles were different from those of the previously explored 1,4-disubstituted sulfonyl-triazoles. It was observed by NMR that the Rh(II)-catalyst coordinates strongly but reversibly with the 1,5-disubstituted sulfonyl-triazoles. Other catalysts, including both Brønsted and Lewis acids, were found to catalyze this transformation, although less efficiently compared to neat thermolysis or Rh(II)-catalyzed conditions. These data illustrate both the unique nature of 1,5-disubstituted sulfonyl-triazoles and potential future avenues for their utilization. [Copyright &y& Elsevier]

Abstract: An efficient and green approach for synthesis of optically active amines was developed via asymmetric transfer hydrogenation of N-sulfonyl ketimines catalyzed by the chiral and lipophilic rhodium-amido complex on water. Higher reactivity and enantioselectivity were observed on the hydrogenation of the solid substrate in an aqueous suspension compared to organic homogeneous phases. In the heterogeneous aqueous reaction, the reactivity depends on stirring speed and the recrystallized conditions of the solid substrate. [Copyright &y& Elsevier]

Abstract: A practical and efficient method for the perfluorobutanesulfonyl azide-mediated one-carbon ring contraction of cyclic enoxysilanes is described. High-yielding procedures for the elaboration of the resulting N-acyl sulfonamide products are reported. [Copyright &y& Elsevier]

Abstract: A silver-catalyzed reaction of 2-alkynylbenzaldoxime with phenol promoted by p-toluenesulfonyl chloride leads to 1-aroxyisoquinolines in good yields. The presence of p-toluenesulfonyl chloride as an activator is essential for the successful transformation. [Copyright &y& Elsevier]

Abstract: The heterobimetallic complex [Ir(COD)(SnCl3)Cl(μ-Cl)]2 catalyzes the aza-Friedel–Crafts reaction of 1,3,5-trimethoxybenzene, as well as substituted indoles with N-sulfonyl aldimines leading to the formation of diarylamines and triarylmethanes in good yields. The symmetrical triarylmethanes were also obtained from diarylamines and suitable nucleophiles via simultaneous cleavage of sp3 C–N bond and elimination of 1,3,5-trimethoxybenzene. [Copyright &y& Elsevier]

Abstract: The synthesis of α-sulfanyl, α-sulfonyl, and α-phosphono carboxylates has been achieved using a two-step procedure involving the in-flow generation of diazoesters from sulfonylhydrazones, via Bamford–Stevens elimination, and then subsequent S–H, sulfinate, and P–H carbene insertion reactions. The method for α-sulfonyl ester is particularly noteworthy as it represents a very atom economic (‘green’) way to access the products, and it completely avoids the use of alkyl halides. [Copyright &y& Elsevier]

Abstract: By using Tf2O as a catalyst, we have developed a protocol for the preparation of various dibenzo[a,d]cycloheptene cores via Friedel–Crafts alkylation. Using this method as the key step, we also present concise and useful routes to synthesize the natural products Diptoindonesin D, Pauciflorial F, and (±)-Ampelopsin B. Notably, this process exhibited following very attractive features: (i) the process is metal free, with only catalytic amounts of Tf2O being employed, and (ii) the process is simple and environmentally conscious, avoiding the use of excess amounts of base, oxidant, or other additives. [Copyright &y& Elsevier]

Abstract: Lactam 2, prepared from deltaline (1), is an analog of C19-diterpenoid alkaloid with a hydroxyl group at C-6 and a ketone carbonyl group at C-7. Treatment of this lactam with thionyl chloride or methanesulfonyl chloride, or reaction of this lactam under Chugaev condition led to an unusual rearrangement of its E/F ring system to yield a lactone 10 in a yield range of 43–74%. The structure of 10 was confirmed by its 2D NMR data and X-ray crystallographic analysis. [Copyright &y& Elsevier]

Abstract: Di-ionizable calix[4]arene-1,3-crown-4 compounds locked in 1,3-alternate, cone, and partial-cone conformations are synthesized for evaluation in metal ion separations. The ionizable functions include carboxylic acid and N-(X)sulfonyl carboxamide groups in which the acidity is tuned by variation of the electron-withdrawing ability of X. Similar synthetic routes were employed for preparation of the cone and 1,3-alternate ligand series. A different preparative route utilizing protection and deprotection was required to obtain the partial-cone analogues. Ligand conformations were confirmed by their proton and/or carbon NMR spectra. X-ray diffraction verified an unusual 1,2-alternate conformation in the solid-state for one synthetic intermediate. Effects of ligand conformation and ionizable group variations on competitive solvent extractions of alkali and alkaline earth metal cations from aqueous solutions into chloroform were assessed. Single species solvent extractions of Hg2+ and Pb2+ were also performed. [Copyright &y& Elsevier]

Abstract: p-Toluenesulfonyl chloride (TsCl)/NaOH has been introduced as reagent combination for the synthesis of 2-amino-oxa- or 2-amino-thiazolidines from N-(2-hydroxyethyl)-thioureas, but its general application in heterocycle synthesis has not been investigated. In this paper the convenient and efficient synthesis of a variety of 2-amino-substituted 1-aza 3-(aza, oxo or thio) heterocycles of different substitution and ring sizes is described. The application of polymer-supported TsCl facilitates work-up and renders the reaction conditions very suitable for parallel or robot synthesis. [Copyright &y& Elsevier]

B 2 Pin 2 -assisted copper-catalyzed transfer hydrogenation of aromatic sulfonylimines has been achieved, delivering a variety of aryl/heteroaryl sulfonamides in good to excellent yields under mild reaction conditions and with methanol as the hydrogen source. Mechanistic studies suggest that the reaction may proceed via a transient α-borylated intermediate, followed by protodeboration to afford the sulfonamide products. [Display omitted] • Copper-mediated catalysis. • Transfer hydrogenation. • Aryl sulfonamides. • Heteroaryl sulfonamides. [ABSTRACT FROM AUTHOR]

Magnesium (II)-BOX complexes catalyze the enantioselective Michael addition of malonates to β-trifluoromethyl enones and their N-sulfonyl imines to give ketones or (E)-enamines bearing a trifluoromethylated stereogenic center, respectively, with good yields and high enantiomeric excesses. Magnesium complexes proved to be more active and stereoselective than zinc and copper analogues in these reactions. Image 1 • Enantioselective Michael addition of malonates to β-trifluoromethyl enones and their imines catalyzed by Mg/BOX complexes. • Ketones and (E)-enamines bearing a trifluoromethylated stereogenic center in good yields and high enantiomeric excesses. • Synthetic methodology to afford chiral building blocks bearing a trifluoromethylated stereogenic center. [ABSTRACT FROM AUTHOR]

The transfer of a α-methyl phenylseleno carbanion to variously functionalized N -aryl and N- sulfonyl imines is reported. The fast selenium-lithium exchange conducted on a diselenoacetal with n -BuLi enables the generation of the attacking homologative nucleophile under chemoselective conditions preserving concomitant potentially sensitive functionalities to the lithiating conditions. Uniformly high yields were observed, thus establishing a valuable and conceptually simple approach to the title compounds. Image 1 [ABSTRACT FROM AUTHOR]

An efficient Ni(ClO 4) 2 ·6H 2 O/SMI-PHOX catalyzed enantioselective addition of arylboronic acids to cyclic N -sulfonyl aldimines is envisioned to afford excellent enantioselectivities (up to 99% ee) in high yields (up to 98%). This protocol offers new opportunities for the synthesis of chiral benzosultams containing a stereogenic tertiary carbon center. The highlights of this method include mild reaction conditions, the use of cheap metal catalyst and a wide substrate scope. Image 1 • A new method was reported for the synthesis of chiral tertiary benzosultams. • A Ni(II)/SMI-PHOX catalyzed asymmetric addition of arylboronic acids was detected. • Milder reaction conditions and wider substrate scope were achieved. [ABSTRACT FROM AUTHOR]

Sulfur (VI) Fluoride Exchange (SuFEx) chemistry is proposed as a new generation of click chemistry with potential in drug discovery and biological study. Herein we report a simple and convenient approach to synthesize amino acid derivatives functionalized with aryl fluorosulfonyl group from a simple building block. Promoted by 1,1′-Carbonyldiimidazole (CDI), methyl protected amino acids and other amines were efficiently functionalized with SO 2 F by the reaction with 4-((fluorosulfonyl)oxy)benzoic acid giving fluorosulfonylated amides (FSAs) as products. We also demonstrated that FSAs are useful building blocks in drug discovery. The conjugation of FSA with pharmaceutical phenols by SuFEx efficiently introduced amino acid moiety into target molecule, providing a series of prodrugs with diverse property. Image 1 • Synthesizing amino acid derivatives functionalized with aryl fluorosulfonyl group efficiently. • Functional compatibility of the method is good, and the scope of the substrates is broad. • Constructing prodrugs with amino acid analogues by SuFEx chemistry readily provides compound library for drug discovery. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of α -amino alkenyl-substituted hydrazone derivatives was disclosed through silver-catalyzed reaction of sulfonyl hydrazones with ynamides. The present method features mild conditions, high stereoselectivity and good yields. The proposed mechanism involves silver-mediated generation of a keteniminium ion intermediate to facilitate the stereoselective addition of hydrazones in the presence of K 2 CO 3 , while pyrazole ring could not be constructed under the current conditions. Image 1 • Synthesis of α -amino alkenyl-substituted hydrazone derivatives was achieved in high efficiency. • The reaction could proceed in a highly stereoselective manner. • This work achieved the alkenylation of NH of hydrazones that was often ignored. [ABSTRACT FROM AUTHOR]