Title : ( A Mild, simple and efficient method for selective α-monobromination of 1,3diketones and β-keto-esters using bis(2-N-methylimidazoliummethyl)ether dichloride )
Authors: mina taheri torbati , Hossein Eshghi , Ali Shiri ,Access to full-text not allowed by authors
Abstract
Background: The α-bromination of carbonyl compounds is an important transformation in synthetic organic chemistry. These compounds are useful synthetic intermediates for various organic transformations [1-3]. On the hand, the importance of green reactions in organic synthesis has encouraged scientists to explore the use of room-temperature ionic liquids as a powerful alternative to the conventional organic solvents or catalysts because of possessing undetectable vapor pressure, wide liquid range, and ease of recovery [4,5]. Methods: To a stirred solution of 1,3-diketones and β-keto-esters in CH2Cl2, a 5 mol % of IL and Br2 was added at room temperature. After the completion of the reaction, the mixture was washed with water and extracted with diethyl ether. The organic layers were combined and dried over anhydrous Na2SO4 and solvent were removed by evaporation in a rotary evaporator to get the product. Results: We have developed an acceptable protocol for α-bromination of dicarbonyl compounds using bis(2-N-methylimidazoliummethyl)ether dibromochlorate. This novel ionic liquid brominated β-dicarbonyl compounds to give a high to excellent yields of the corresponding monobrominated compounds. Conclusion: We have developed a green method for the efficient α-monobromination of dicarbonyl compounds using bis(2-N-methylimidazoliummethyl)ether dibromochlorate as a new ionic liquid. Keywords: α-bromination; ionic liquid; β-dicarbonyl compounds; dibromochlorate References [1]Meshram, H. M.; Reddy, P. N.; Vishnu, P.; Sadashiv, K.; Yadav, J. S. Tetrahedron Lett. 2006, 47, 991 [2]Rahman, A.; Jonnalagadda, S. B. Synth. Commun. 2012, 42, 1091 [3]Yang, D.; Yan, Y.-L.; Lui, B. J. Org. Chem. 2002, 67, 7429. [4]Eshghi, H.; Bakavoli, M.; Ghasemzadeh, M.; Seyedi, S. M. Chem. Intermed 2013. doi:10.1007/ s11164-013-1302-1 [5]Zavozin, A. G.; Kravchenko, N. E.; Ignatev, N. V.; Zlotin, S. G. Tetrahedron Lett. 2010, 51, 545.
Keywords
, bis(2, N, methylimidazoliummethyl)etherdichloride@inproceedings{paperid:1049284,
author = {Taheri Torbati, Mina and Eshghi, Hossein and Shiri, Ali},
title = {A Mild, simple and efficient method for selective α-monobromination of 1,3diketones and β-keto-esters using bis(2-N-methylimidazoliummethyl)ether dichloride},
booktitle = {18th Iranian Chemistry Congress},
year = {2015},
location = {سمنان, IRAN},
keywords = {bis(2-N-methylimidazoliummethyl)etherdichloride},
}
%0 Conference Proceedings
%T A Mild, simple and efficient method for selective α-monobromination of 1,3diketones and β-keto-esters using bis(2-N-methylimidazoliummethyl)ether dichloride
%A Taheri Torbati, Mina
%A Eshghi, Hossein
%A Shiri, Ali
%J 18th Iranian Chemistry Congress
%D 2015