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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]

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]

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]

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]

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]

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]

Novel halactolactonizations using NBS (2), NIS(3), and NSP(4) in dry DMF were found to be the most reasonable and efficient procedures. The participation of X as the cyclization initiator could be clearly rationalized by experimental results and the regioselectivities of formed halolactones were reasonably elucidated by weakly bridged carbonium ion intermediate. [ABSTRACT FROM AUTHOR]

A letter to the editor in response to the article "Unusual Effect of a Remote Substituent on Chlorination of Melatonin," by T. I. Bidylo and M. A. Yurovskaya is presented.