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A facile synthetic protocol has been established for the N‐chlorosuccinimide (NCS) promoted direct C−H thiocyanation of 1‐aryl‐5‐pyrazolones via in situ‐generated electrophilic thiocyanating agent at room temperature. The current protocol features easy performance, mild conditions and short reaction time using readily available starting materials. The DFT studies suggested that ionic process is likely to be involved in this transformation yielding the targeted product with the most stable enaminone form as the favoured tautomer. [ABSTRACT FROM AUTHOR]

Carbon‐supported Au (Au/AC) has been proven to be one of the most promising catalysts in the field of acetylene hydrochlorination. However, the catalytic performance of conventional Au/AC catalyst is usually limited due to the unsatisfactory dispersion of active Au cation on the surface of the support, carbon deposition, and inevitable reduction to inactive Au nanoparticles. Herein, Au catalysts with highly dispersed Au cation were developed using the complexation of dicarbonyl ligand N‐chlorosuccinimide (NCS) and N‐methylsuccinimide (NMS). The obtained Au−NMS/AC and Au−NCS/AC catalysts with 0.1 wt.% Au loading possessed acetylene conversion of 98 % and 88 % at 180 °C and GHSV (C2H2) of 160 h−1, which were clearly better than that of pristine Au/AC. The characterization results showed that coordination between Au cation and ligands enhanced the dispersion of Au species, suppressed the reduction of Au cation, and reduced the formation of carbon deposits. Density functional theory (DFT) calculations suggest that Au−NMS/AC and Au−NCS/AC catalysts follow a HCl‐preferred concerted addition reaction mechanism with lower reaction energy barrier. This favors the high activity and nuclearity stability of the Au center. This study provides great potential for the use of dicarbonyl ligands on Au‐based catalysts in acetylene hydrochlorination. [ABSTRACT FROM AUTHOR]

A method for preparation of alkyl 3‐aryl‐(1,2,4‐oxadiazol‐5‐yl)propanoates by base‐catalyzed domino reaction of an aryl aldoxime with N‐chlorosuccinimide in alcohol is described. In this reaction, initially aldoxime and N‐chlorosuccinimide react to produce hydroximidoyl chloride and succinimide. The hydroximidoyl chloride and base produces nitrile oxide which undergoes [3+2] annulation with succinimide followed by ring opening reaction with the assistance of alcohol to give alkyl 3‐aryl‐(1,2,4‐oxadiazol‐5‐yl)propanoates in 65–95% yield. [ABSTRACT FROM AUTHOR]

Kinetics of Ir(III) catalysed oxidation of tartaric acid (TA) by N-chlorosuccinimide (NCS) in the presence of perchloric acid has been investigated in the temperature range of 300C to 450C. The reaction shows first order in both (NCS) and Ir (III)] and zero order in [(TA)]. First order kinetics with respect to [H+] was observed. Addition of chloride ions in the form of various amounts of KCl indicated positive effect of [Chloride] ions on the rate. Addition of various amounts of succinimide (reduction product of NCS) and increase in ionic strength of the medium showed negative effect on the rate of the reaction. Activation parameters have been calculated and reported. A suitable mechanism has been proposed and discussed. Rate law in conformity with observed kinetic results has been derived. [ABSTRACT FROM AUTHOR]

The cascade amination/cyclization of N‐arylacrylamides with alkyl amines under visible‐light photoredox catalysis is realized via intermediacy of aminium radicals. The aminium radicals are generated by a two‐step sequence which involves N‐chlorination of alkyl amines and subsequent reductive N−Cl cleavage. This method provides a convenient access to aminated oxindoles. [ABSTRACT FROM AUTHOR]

Chlorination of 1-hydroxyindole-5,6-dicarbonitriles and 1-hydroxypyrrolo[3,4-f]indole-5,7(1H,6H)-diones with N-chlorosuccinimide afforded previously unknown 3,3-dichloro-3Hindole 1-oxides instead of the expected 3-chloro-1-hydroxyindoles. The latter, however, were prepared in good yields by treatment of the above 3,3-dichloro-3H-indole 1-oxides with piperidine in ethanol. Reduction of 3,3-dichloro-5,6-dicyano-3H-indole 1-oxides with Zn in AcOH yielded the corresponding 3-chloroindole-5,6-dicarbonitriles. [ABSTRACT FROM AUTHOR]

A simple and efficient one-pot protocol is accomplished to access tricyclic spiro dihydrofurans (4) by the reaction of β -enamino ketones (1) and dimedone (2) in ethanol followed by sequential addition of N-chlorosuccinimide at ambient temperature for the first time. The selectivity in desired product formation in good yields is the advantage of this protocol. [ABSTRACT FROM AUTHOR]

1,4-Diazabicyclo[2.2.2]octane (DABCO) is a suitable Lewis base that acts as an organocatalyst in the activation of N-chlorosuccinimide (NCS) towards the chlorination of alkenes. The chloriranium ion formed from NCS and the alkene, can be intermolecularly opened by a nucleophile, such as acetic acid, to produce highly functionalized trans-chloro esters in high yields. The protocol is also applied to the synthesis of chlorohydrins and chloro ethers using water or methanol as nucleophiles instead of acetic acid. Brominated analogs can also be synthesized from alkenes and N-bromosuccinimide (NBS) in the presence of various basic catalysts. However, the reaction patterns seem to be remarkably different. The catalytic performance of bases in the bromoesterification of alkenes was found to be strongly affected by their Brønsted basicity, suggesting that acetyl hypobromite, formed in situ from NBS and acetic acid, acts as a real brominating agent in these systems. [ABSTRACT FROM AUTHOR]

A novel fluorous hydrazine-1,2-bis(carbothioate) was prepared. It showed good catalytic activity in the synthesis of β-chloroethers with N-chlorosuccinimide under mild reaction conditions. This fluorous organocatalyst could be recovered and recycled several times with good purity. [ABSTRACT FROM AUTHOR]

A simple and efficient protocol for the electrophilic thiocyanation of indoles and aromatic amines with thiourea/NCS/NH4SCN system has been developed. The major features of the present procedure are the mild conditions, good yields, short reaction times, and the use of inexpensive and readily available organocatalyst. Moreover, N-chlorosuccinimide (NCS) was found to be indispensable, and thiourea could greatly promote the reaction. [ABSTRACT FROM AUTHOR]

Sulfenylchloride intermediates generated from the reaction of aryl thiols with N-chlorosuccinimide were trapped by 6-amino uracil derivatives to yield 6-amino-5-(arylthio)-pyrimidine-2,4(1 H,3 H)-dione compounds at room temperature. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Treatment of 1-phenylthiomethyl-3,5-dimethylpyrazole with n -butyllithium, and subsequently with phenyl isothiocyanate yielded 2-(3,5-dimethylpyrazol-1-yl)-2-(phenylthio)thioacetanilide, 2-(3,5-dimethylpyrazol-1-yl)thioacetanilide, N,N ′-diphenyl-2-(3,5-dimethylpyrazol-1-yl)propanedithioamide and 5-anilino-4-(3,5-dimethylpyrazol-1-yl)-3-phenylimino-1,2-dithia-4-cyclopentene, respectively. Reaction of the propanedithioamide derivative with W(CO) 5 THF has been investigated, which gave a bis(chelate) tungsten complex through two relatively soft sulfur atoms. All these newly synthesized compounds were characterized by NMR and HRMS spectroscopy (or elemental analysis), and their structures were unambiguously confirmed by X-ray crystallography. Two possible pathways, including a carbanion or a carbene intermediate formed via the C S bond cleavage, have been suggested to explain the formation of propanedithioamide and 1,2-dithiole derivatives. [ABSTRACT FROM AUTHOR]

A novel and recoverable fluorous hydrazine-carbothioate organocatalyst was prepared. It could catalyze α-chlorination of alkyl ketones with N-chlorosuccinimide as chlorine source under mild reaction conditions. The reaction afforded the corresponding α-chlorinated carbonyl compounds with excellent yields at rapid reaction speed. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The of 2-oxazolidinone with (HOCl), tert-butyl hypochlorite (tBuOCl) and N-chlorosuccinimide (NCS) were studied at 25 °C, constant ionic strength, and under isolation conditions. The kinetic results obtained in the formation processes of the N-chloro-2-oxazolidinone are summarized in this paper. The kinetics studied showed a first order with respect to the concentration of the each reactant and a complex dependence of the pH on the rate constant. The reactivity order with respect to the chlorinating agent found is k(HOCl) > k(tBuOCl) > k(NCS). Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Pd(IV) species, known to be critical intermediates in homogeneous catalysis, were successfully generated on the surface of Pd nanocatalysts via oxidation with iodobenzene dichloride (PhICl2) or N-chlorosuccinimide (NCS). In particular, the Pd@SiO2 yolk--shell nanocatalyst activated by PhICl2 showed high reactivity and superior stability to the other Pd-based catalysts for hydroalkoxylation reactions even at 25 °C. [ABSTRACT FROM AUTHOR]

A novel post-chemiluminescence (PCL) reaction was discovered when lercanidipine was injected into the CL reaction mixture of N-chlorosuccinimide with alkaline eosin Y in the presence of cetyltrimethylammonium bromide (CTAB), where eosin Y was used as the CL reagent and CTAB as the surfactant. Based on this observation, a simple and highly sensitive PCL method combined with a flow injection (FI) technique was developed for the assay of lercanidipine. Under optimum conditions, the CL signal was linearly related to the concentration of lercanidipine in the range 7.0 × 10-10 to 3.0 × 10-6 g/mL with a detection limit of 2.3 × 10-10 g/mL (3σ). The relative standard deviation (RSD) was 2.1% for 1.0 × 10-8 g/mL lercanidipine (n=13). The proposed method had been applied to the estimation of lercanidipine in tablets and human serum samples with satisfactory results. The possible CL mechanism is also discussed briefly. [ABSTRACT FROM AUTHOR]

Second-order rate constants were determined for the reaction of 2,2,2-trifluoethylamine and benzylamine with N-chlorosuccinimide at 25 °C and an ionic strength of 0.5 M. These reactions were found to be of first order in both reagents. According to the experimental results, a mechanism reaction was proposed in which a chlorine atom is transferred between both nitrogenous compounds. Kinetics studies demonstrate that the process of the chlorinating agent does not interfere in the process, under the experimental conditions used in the present work. Free-energy relationships were established using the results obtained in the present work and others available in the literature for with N-chlorosuccinimide, being the p Ka range included between 5.7 and 11.22. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel immobilized N-chlorosuccinimide resin was developed for peptide disulfide bond formation in combinatorial libraries. The resin is prepared in a simple two-step process from commercial starting materials. Disulfide formation is initiated by adding a peptide solution to the resin, and excess reagent is removed by a convenient filtration upon completion of disulfide formation. Completion of disulfide formation is rapid and clean, as demonstrated by the oxidation of a small nonapeptide library. This immobilized reagent allows a wider scope for the use of N-chlorosuccinimide-based disulfide formation in combinatorial chemistry. [ABSTRACT FROM AUTHOR]

A very simple N-chlorosuccinimide-promoted synthesis of thiophosphates through the coupling of thiols and phosphonates is reported. Notably, the reactions were carried out in the absence of a base. Functional groups including fluoro, bromo and trifluoromethyl are all tolerated by the reaction conditions employed. Both aryl and alkyl thiols are coupled smoothly with a broad spectrum of phosphonates to afford the corresponding thiophosphates in good to excellent yields. [ABSTRACT FROM AUTHOR]

A convenient, practical, and environmentally friendly method for the synthesis of sulfonyl chlorides has been developed. Structurally diverse sulfonyl chlorides were synthesized in moderate to excellent yields from S-alkylisothiourea salts, which can be easily prepared from readily accessible alkyl halides or mesylates and inexpensive thiourea, via N-chlorosuccinimide chlorosulfonation. In large-scale syntheses, the byproduct succinimide from 'waste water' can be conveniently converted into the starting reagent N-chlorosuccinimide with sodium hypochlorite (bleach) to make the method sustainable. [ABSTRACT FROM AUTHOR]

Oxidative difunctionalination of 2-amino-4H-pyrans was accomplished with iodobenzene diacetate (1BD) and N- chlorosucdnimide (NCS) reagents in alcoholic medium. 2-Amino- 4J-i-pyran.s undergo gcminal dialkoxylation with the migration of an amino group (la,b, 2a--i, 3a,b, and 4) in 1BD, whereas with NCS addition of both chlorine and alko*y groups takes place across the chiomenc double bond (6a--i). [ABSTRACT FROM AUTHOR]

A series of 2-hydroxyaryl ketoximes were converted to the corresponding 1,2-benzisoxazole 2-oxides by treatment with iodobenzene diacetate (in acetic acid or methanol) or N-chlorosuccinimide in water. Both methods gave moderate to excellent yields for a variety of substituted oximes under mild conditions within short reaction times. The latter method has the advantages of an aqueous solvent and lack of halogenated organic by-products. [ABSTRACT FROM AUTHOR]

A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with N-chlorosuccinimide (NCS), tetrabutylammonium chloride, and water. The sulfonyl chlorides are then further allowed to react with excess amine or sodium azide in the same reaction vessel. [ABSTRACT FROM AUTHOR]

Two N-chloro reagents (chloramine-T and N-chlorosuccinimide) were used as effective oxidizing agents for the oxidation of bisnaphthols to the corresponding Abel's ketones under mild and convenient conditions at room temperature with good to excellent yields. [ABSTRACT FROM AUTHOR]

A mixture of N-chlorosuccinimide and 1,8-diazabicyclo[5.4.0]undec-7-ene oxidatively cyclizes structurally diverse acyl hydrazone, thereby providing an efficient and convenient method for the synthesis of various 2,5-disubstituted 1,3,4-oxadiazoles. The salient features of this method are mild reaction conditions, short reaction time, excellent yields, and simple workup procedure. [ABSTRACT FROM AUTHOR]

Abstract: Solid additives participate in the dry microwave assisted chlorination reaction of N-chlorosuccinimide with the xylenes affecting both yields and chemoselectivities. Total yields can be increased up to nine times for simple alkylaromatics and chemoselectivities can be altered according to the desired ring or α-side chlorination product by choosing the appropriate additive. We believe that in these reactions the solid additives play a very important role by increasing yields and affecting chemoselectivities, as well as behaving as microwave energy absorbers that consequently aid the transfer of heat to the active reagents. [Copyright &y& Elsevier]

Aniline undergoes regioselective trichlorination by N-chlorosuccinimide (NCS) in acetonitrile in good yield. The product 2,4,6-trichoroaniline was converted into 1,3,5-trichlorobenzene by reduction of its diazonium salt. Reaction of the methyl carbamate of aniline with NCS gave only the 2,4-dichlorophenyl carbamate. [ABSTRACT FROM AUTHOR]

Aldehydes and ketones are easily converted to their corresponding gem-dichlorides using a mixture of chlorodiphenylphosphine and N-chlorosuccinimide (ClPPh2/NCS) in dichloromethane under neutral conditions and at room temperature. [ABSTRACT FROM AUTHOR]

4(5)-Chloro-imidazole-5(4)-carboxaldehyde derivatives are important precursors for the preparation of biologically active compounds. We developed a simple, novel, and efficient method for the synthesis of these compounds. The chemistry described is amenable to large-scale use and is flexible enough to allow the preparation of analogs. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of N-(2-arylcyclohex-1-en-1-yl)-α-(methylthio)acetamides with N-chlorosuccinimide (NCS) gave 3a-aryl-2,3,3a,4,5,6-hexahydro-3-(methylthio)indol-2-ones. Desulfurization of the cyclization products followed by a catalytic hydrogenation of the resulting hexahydroindol-2-ones gave predominantly or exclusively trans-fused octahydroindol-2-ones. On the other hand, reduction of the desulfurization products with Et3SiH in CF3CO2H exclusively provided cis-fused octahydroindol-2-ones. A chiral induction of N-[2-(3,4-dimethoxy)phenylcyclohex-1-en-1-yl]-α-(methylthio)acetamide having an (R)-1-(1-naphthyl)ethyl group on the nitrogen atom led to the synthesis of (−)-mesembrane and (−)-trans-mesembrane. [Copyright &y& Elsevier]

Reacting methyl isoricinoleate with N-bromosuccinimide in the presence of excess diols [mono-, di-, tri-, and tetraethylene glycol] gave the 1,4-epoxy derivative in 80% yield along with the respective ß-bromoethoxylates as minor products (20%). However, when the reaction was carried out with N-chlorosuccinimide, the yield of 1,4-epoxy derivative was reduced to 20%, and formation of ß-chloroethoxylates was increased to 80%. [ABSTRACT FROM AUTHOR]

Olefinic fatty methyl esters, undec-10-enoate ( 1), octadec- Z-9-enoate ( 2), methyl-12 hydroxy octadec- Z-9-enoate ( 3), on reaction with N-halosuccinimides ( 4,5), that is, N-bromosuccinimide ( 4) or N-chlorosuccinimide ( 5) and 2-mercaptoethanol ( 6) in benzene, gave β-bromo- or β-chlorothioethoxylates ( 8–13). β-Halothioethoxylates so formed were acetylated with acetyl chloride in CH2Cl2 to form the respective acetylated products ( 20–25). [ABSTRACT FROM AUTHOR]

Abstract: A mild two-step synthesis of perfluoroalkanesulfonyl chlorides starting from perfluoroalkyl iodides has been developed. Reaction of perfluoroalkyl iodides with sodium dithionite gave sodium perfluoroalkanesulfinate salts which were converted into perfluoroalkanesulfonyl chlorides in 25–73% yield (two steps) using N-chlorosuccinimide. [Copyright &y& Elsevier]

Primary amides and aldoximes are easily converted to their corresponding nitriles using a mixture of triphenylphosphine and N-chlorosuccinimide in dichloromethane at room temperature. The reaction of aldoximes occurs almost immediately and primary amides in 0.5 h by this method. By this procedure secondary amides are produced by Beckmann rearrangement of ketoximes. [ABSTRACT FROM AUTHOR]

The ruthenium(III) catalyzed oxidation of dimethyl sulfoxide by N-chlorosuccinimide (NCS) in aqueous alkaline medium is found to occur via substrate-catalyst complex formation followed by the interaction of active species of NCS viz., HOCl and the complex in a slow step to yield the products with regeneration of the catalyst. One of the products, succinimide, retards the rate of reaction. The reaction is first order in [NCS] and [Ru(III)], lower than first order in [DMSO] and of inverse fractional order in [OH]. A suitable mechanism is proposed and the reaction constants of individual steps involved in the mechanism have been evaluated. [ABSTRACT FROM AUTHOR]

An efficient method to prepare 1-chloroalkynes was investigated. The method involved the use of readily available terminal alkynes and a catalytic amount of a silver salt with N-chlorosuccinimide as the chlorinating agent under mild conditions. Compared with the existing process, this method has a broad substrate scope: 19 examples were explored, and the products were obtained in excellent yields and were easily isolated by vacuum distillation. Moreover, recycling of the catalyst was achieved by simple filtration and desiccation, which made the method more economic and environmentally benign. [ABSTRACT FROM AUTHOR]

New spectrophotometric and titrimetric methods for the determination of sulphonamides with N-chlorosuccinimide (NCS) were developed. The spectrophotometric measurements can be made at 324-395 nm at pH 7.4 at room temperature, the stoichiometry being 1: 2, ( p-HN-CH-SONHR): (NCS) forming a dibromination product in presence of acidified potassium bromide. Potentiometrically or visually using methyl red as indicator, sulphonamides are titrated in pharmaceutical preparations by NCS always in presence of acidified potassium bromide. Ascorbic acid is determined alone and also in combinations, by first titrating it using potassium iodide and starch or 2,6-dichlorophenolindophenol as indicator. Acylation or diazotization of the aromatic amino groups that prevents substitution at the two ortho positions, is used as additional prereaction to analyze various binary and ternary mixtures of certain sulphonamides. These methods are accurate, simple, rapid, reproducible, useful at higher concentrations, do not involve any preseparation, and can tolerate several compounds that cause interference in other methods. [ABSTRACT FROM AUTHOR]