L-Butyl-3-methylimidazolium bromide

Multicomponent reactions have been described for several syntheses of imidazoles. Highly efficient methods for the syntheses of spiroimidazolinones via microwave-assisted three-component one-pot sequential reactions or one-pot domino reactions have been described <06JOC3137>. Multicomponent reactions between 2-aminopyrimidine, aldehydes and isonitriles afforded imidazo[l,2-a]pyrimidines <06TL947>. Two novel one-step microwave mediated syntheses of arrays of 3-iminoaryl-imidazo[l,2-a]pyridines and imidazo[l,2-a]pyridyn-3-ylamino-2-acetonitriles were synthesized by multicomponent reactions under microwave condition in methanol by simply mixing a-aminopyridines, aldehydes, and trimethylsilylcyanide catalyzed by polymer-bound scandium triflate <06TL2989>. 3-Aminoimidazo[l,2-a]pyridines have been synthesized via the multicomponent reaction of aldehydes, isocyanides and 2-aminopyridines in the presence of the ionic liquid l-butyl-3-methylimidazolium bromide [bmim]Br<06TL3031>. 

Shaabani and co-workers reported the synthesis of furo[2,3-d]pyrimidine-2,4 (lH,3H)-diones via the three-component condensation of -dimethylbarbituric acid, aldehyde, and an alkyl or aryl isocyanide in l-butyl-3-methylimidazolium bromide ([bmim][Br]) as the solvent and promoter at room temperature (Fig. 12.17) [13]. 

The aerobic oxidation of alkyl arenes and alcohols to the corresponding carbonyl compounds have been achieved using cobalt(II) phthalocyanine (CoPc) as catalyst and oxygen (0.1 atm) in the ionic liquid l-butyl-3-methylimidazolium bromide ([bmim][Br]). Excellent yields were obtained under mild and easily obtainable conditions [36]. 

Shekouhy, M. and Hasaninejad, A. 2012. Ultrasound-promoted catalyst-free one-pot four component synthesis of 2//-indazolo[2,l- ]phthalazine-triones in neutral ionic liquid l-butyl-3-methylimidazolium bromide. Ultrason. Sonochem. 19 307-313. 

Grishina EP, Vladimirova TV, Ramenskaya LM, Shilovskii KS (2007) Anodie oxidatitm of silver in l-butyl-3-methylimidazolium bromide ionie liquid. Russ J Electroehem 43 234—237... 

Zare A, Hasaninejad A et al (2010) Ionic liquid l-butyl-3-methylimidazolium bromide ([bmimJBr) a green and neutral reaction media for the efficient, catalyst-free synthesis of quinoxaline derivatives. J Serb Chem Soc 75 1315-1324... 

Imanari, M., Nakakoshi, M. Seki, H., Nishikawa, K. (2008) iH NMR Study on Reorientational Dynamics of an Ionic Liquid, l-Butyl-3-methylimidazolium Bromide, Accompanied with Phase Transitions, Chem. Phys. Lett. Vol. 511 241-246. 

The compounds l-ethyl-3-methylimidazolium tetrafluoroborate ([EMlm][BF4]), l-butyl-3-methylimidazolium tetrafluoroborate ([B-Mlm][BF4]), l-hexyl-3-methylimidazolium tetrafluoroborate ([H-Mlm][BF4]) and l-butyl-3-methylimidazolium bromide ([BMlm]-[Br]) were used as ionic liquids. Some of these compounds are shown in Figure 1.7. Some properties are summarized in Table 1.3. 

Sadeghi R, Golabiazar R, Shekaari H (2010) The salting effect and phase separation in aqueous solutions of tri-sodium citrate and l-butyl-3-methylimidazolium bromide. J Chem Thermodyn 42 441-453... 

E. Soleimani, M.M. Khodaei, A.T.K. Koshvandi, Three-component, one-pot synthesis of benzo[l ][l,4]oxazines in ionic liquid l-butyl-3-methylimidazolium bromide, Syn. Commun. 42 (2012) 1367-1371. 

Kim K-S, Shin B-K, Lee H (2012) Physical electrochemical properties of l-butyl-3-methylimidazolium bromide, l-butyl-3-methylimidazolinm iodide, and l-butyl-3-methylimidazolinm tetrafluoroborate. Korean J Chem Eng 21 1010-1014... 

In recent years, ionic liquids have become extremely popular as a green alternative to conventional reaction solvents. Given that a number of the most popular ionie liquids used are 1,3-dialkylated imidazolium salts, their true role in transition metal catalysed reactions, particularly in the presence of base, must be scrutinised. Following the initial report of a successful Mizoroki-Heck reaction performed in an ionic liquid by Earle and co-workers, Xiao and co-workers were able to isolate a number of isomeric [(NHC)2PdBr2] complexes from the reaction mixture [eqn (2.6)]. Under stoichiometric conditions, heating [Pd(OAc)2] and sodium acetate in the ionic liquid, BMIM HBr (l-butyl-3-methylimidazolium bromide), the dimeric palladium carbene complex, [(BMIM)PdBr(p-Br)]2 could be readily obtained, which upon further heating generated bis(NHC)-Pd complexes. 

Santos PS, Ando RA, Siqueira LJA, Bazito FC, Torresi RM (2007) The sulfur diojdde-l-butyl-3-methylimidazolium bromide interaction drastic changes in structural and physical properties. J Phys Chem B 111(30) 8717-8719. doi 10.1021/jp0743572... 

Kim, K., Shin, B., Lee, H. Ziegler, F. (2004). Refractive index and heat capacity of l-butyl-3-methylimidazolium bromide and l-butyl-3-methylimidazolium tetrafluoroborate, and vapor pressure of binary systems for l-butyl-3-methylimidazolium bromide plus trifluoroethanol and l-butyl-3-methylimidazolium tetrafluoroborate plus trifluoroethanol. Fluid Phase Equilibria, Vol. 218, No. 2, pp. 215-220. 

Zafarani-Moattar, M.T. Shekaari, H. (2005). Apparent molar volume and isentropic compressibility of ionic liquid l-butyl-3-methylimidazolium bromide in water, methanol, and ethanol at T = (298.15 to 318.15) K. J.Chem.Thermodynamics 37, 10 (Oct. 2005)1029-1035. 

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