Improved and ligand-free copper-catalyzed cyclization for an efficient synthesis of benzimidazoles from <i>o</i>-bromoarylamine and nitriles
作者:Emmanuel Mintah Bonku、Hongjian Qin、Abdullajon Odilov、Safomuddin Abduahadi、Samuel Desta Guma、Feipu Yang、Fuqiang Zhu、Haji A. Aisa、Jingshan Shen
DOI:10.1039/d4ra00245h
日期:——
improved copper-catalyzed cyclization for an efficient synthesis of benzimidazoles from o-bromoarylamine and nitriles, under mild and ligand-free conditions. The optimal conditions yielded exceptional products of up to 98%, demonstrating the broad applicability of this synthetic strategy in generating a wide range of valuable imidazole derivatives. This methodology enables the efficient synthesis of various
Identification of bromination products of chloro-substituted anilines in aqueous environment by gas chromatography
作者:I. V. Gruzdev、M. V. Filippova、I. G. Zenkevich、B. M. Kondratenok
DOI:10.1134/s1070427211100132
日期:2011.10
To reduce the detection limits of aniline and its various chloroderivatives (all isomers of mono- and dichloroanilines, 2,4,5 -, 2,4,6-, and 3,4,5-trichloroanilines, pentachloroaniline) in aqueous media we suggested bromination reaction, followed by gas chromatographic definition bromo derivatives of chloroanilines on a selective electron capture detector. To identify the products of bromination of chloroaniline in combination with mass-spectrometric data we used chromatographic retention indices on standard nonpolar polydimethylsiloxane stationary phase that was determined for 50 compounds in this class. The technique of identifying bromoderivatives of chloroaniline in water was developed at the gas-chromatographic analysis in the selective electron capture detector. To improve the reliability of the identification of additional bromoderivatives of chloroanilines we obtained their trifluoroacetyl derivatives.