Reaction of adamantane series olefins with N-bromosuccinimide

Features of allyl bromination of sterically hindered adamantane series olefins with N-bromosuccinimide were investigated. A series of unsaturated mono- and polybromo adamantane derivatives was synthesized. The configuration of compounds obtained was established using 2D NOESY NMR spectroscopy.     

The use of ozone as a titrimetric agent for the quantitative determination of olefinic unsaturation

A new method is described for the determination of olefinic unsaturation, using a constant stream of ozone as the titrimetric agent. A dye is employed as the end-point indicator. The ozone is prepared by electrolysis of dilute sulphuric acid.The method is shown to possess a number of advantages over the methods so far in use for determining unsaturation. It may be satisfactorily applied to a wide variety of substituted as well as unsubstituted unsaturates.     

Reaction of chalcones with N-bromosuccinimide. Synthesis of aurones

The reaction of 2-OR-4-R¹ chalcone with N-bromosuccinimide is reported. It was found that the structure of the product depends on the nature of the substituents R and R¹. The prepared -bromo--methoxydihydrochalcones were converted to the corresponding aurones.T. G. Shevchenko State University, Kiev 252601. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 496–504, April, 1995. Original article submitted March 10, 1995.     

Spectrofluorimetric determination of acetaminophen with N-bromosuccinimide

A simple, sensitive, and selective method for determination of acetaminophen based on its oxidation using N-bromosuccinimide (NBS) to produce a highly fluorescent product. Optimization of reaction variables was carried out concerning NBS concentration, pH, temperature, reaction time, and stability time. Under optimal analytical conditions, the fluorescent intensity was measured at lambda emission. 442 nm (excitation at lambda 330 nm). The linearity range is 120-800 ng/mL with lower detection limit of 33.6 ng/mL acetaminophen. The method was applied successfully to the determination of the compound in pharmaceutical preparations, with average recovery of 100.3 +/- 2%. The method was also applied successfully to the determination of the drug in spiked plasma samples, with an average recovery of 101.2 +/- 1%. Interference effects of some compounds, present in combination with acetaminophen, were studied and the tolerance limits of these compounds were determined.     

Reactions of 1,2,3-triphenylcyclopropene with N-bromosuccinimide in various polar solvents

Conclusions A study was made of the reactions of 1,2,3-triphenylcyclopropene with N-bromosuccinimide in alcohol, acetic acid, aqueous DME, and also anhydrous DMSO. The direction and stereochemistry of these reactions were established.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 234–237, January, 1977.     

Determination of azo compounds with N-bromosuccinimide in acetic acid medium

The bromination reaction of azo compounds with N-bromosuccinimide in acetic acid medium has been studied. Some reaction products have been isolated and reaction mechanisms suggested. The reaction study has been applied for the determination of 2-10 mg of azo compounds. The maximum deviation of the results from the theoretical value is generally within +/- 1%.     

A.C. polarographic determination of unsaturation

A wide range of olefins can be determined by a.c. polarography of their addition compounds with mercuric acetate. The first step in the reduction of these compounds is a reversible, one-electron process to form the organo-mercury radical and gives a well defined a.c. peak. The optimum conditions for the determination of a representative selection of olefins has been established.     

Reaction of vinyl ketoximes with N-bromosuccinimide. Synthesis of isoxazoles and 4-bromoisoxazolines

The reaction of some selected α,β-unsaturated oximes with N-bromosuccinimide gave isoxazoles or 4-bromoisoxazolines in moderate to good yields.     

Continuous-flow chemiluminescence determination of isoniazid by oxidation with N-bromosuccinimide

A rapid and precise continuous-flow method is described for the determination of isoniazid (0.050-20.0 micrograms ml(-1)) based on the chemiluminescence produced during its reaction with N-bromosuccinimide in alkaline medium. The emission intensity is greatly enhanced by the presence of ammonia. The procedure is automated and samples can be analysed at a rate of 112 solutions per hour with a relative error of about 2%. When applied to tablets, the method is relatively free from interferences from common excipients and co-existing compounds. The results obtained for the assay of commercial preparations compared well with those obtained by an official chemical method and demonstrated good accuracy and precision.     

Milligram determination of aromatic amines and phenols with N-bromosuccinimide

A simple and rapid method has been developed for the determination of milligram amounts of aromatic amines and phenols. An aliquot containing 2-4 mg of sample is dissolved in a mixture of hydrochloric and acetic acids and allowed to react with N-bromo-succinimide, the excess of which is determined iodometrically after the reaction is over. The reaction time varies from 1-10 min and the absolute error generally is negative, ranging from -1 to -4%.