Abstract
Background: Recently, organic synthesis using ionic liquids (ILs) via green approach has attracted considerable attention to address the problem associated with environmental pollution. Magnetization of ILs provides added advantages of separation by external magnet. This can be accomplished by incorporation of high-spin iron(III) in the form of tetrachloro or tetrabromoferrate( III). Thus, synthesis of novel magnetically separable ILs for organic transformations is highly desirable.
Results: [AcMIm]FeCl4 ionic liquid showed excellent catalytic activity in the one pot threecomponent synthesis tetrahydrobenzo[b]pyran derivatives at room temperature in excellent yields (94-98 %) within short reaction time (15-20 min.). The ILs were recovered and reused for at least six times with the minimum loss of catalytic activity.
Methods: Here, we have demonstrated the excellent catalytic activity of acid functionalized magnetic Ils, [AcMIm]FeCl4 in one-pot multicomponent reactions for the synthesis of biologically important tetrahydrobenzo[b]pyran derivatives.
Conclusion: A facile and convenient methodology has been developed for the synthesis of bio-active tetrahydrobenzo[b]pyran derivatives using [AcMIm]FeCl4 ionic liquid as an sufficient and reusable catalyst under environment-benign conditions.
Keywords: [AcMIM]FeCl4, clean synthesis, catalytic, magnetically separable organocatalyst, tetrahydrobenzo[b]pyran derivatives, tetrachloro or tetrabromoferrate(III).
Graphical Abstract
(b) Plechkova, N.V.; Seddon, K.R. Applications of ionic liquids in the chemical industry. Chem. Soc. Rev., 2008, 37(1), 123-150.
(b) Sun, X.; Luo, H.; Dai, S. Ionic liquids-based extraction: A promising strategy for the advanced nuclear fuel cycle. Chem. Rev., 2011, 112(4), 2100-2128.
(b) Zhang, Q.; Shreeve, J.n.M. Energetic ionic liquids as explosives and propellant fuels: A new journey of ionic liquid chemistry. Chem. Rev., 2014, 114(20), 10527-10574.
(c) Zhang, S.G.; Miran, M.S.; Ikoma, A.; Dokko, K.; Watanabe, M. Protic ionic liquids and salts as versatile carbon precursors. J. Am. Chem. Soc., 2014, 136(5), 1690-1693.
(d) Smiglak, M.; Pringle, J.M.; Lu, X.; Han, L.; Zhang, S.; Gao, H.; MacFarlane, D.R.; Rogers, R.D. Ionic liquids for energy, materials, and medicine. Chem. Commun., 2014, 50(66), 9228-9250.
(e) MacFarlane, D.R.; Tachikawa, N.; Forsyth, M.; Pringle, J.M.; Howlett, P.C.; Elliott, G.D.; Davis, J.H.; Watanabe, M.; Simon, P.; Angell, C.A. Energy applications of ionic liquids. Energy Environ. Sci., 2014, 7(1), 232-250.
(b) Hayashi, S.; Saha, S.; Hamaguchi, H. A new class of magnetic fluids: bmim[FeCl/sub 4/] and nbmim[FeCl/sub 4/] ionic liquids. IEEE Trans. Magn., 2006, 42(1), 12-14.
(c) Sitze, M.S.; Schreiter, E.R.; Patterson, E.V.; Greeman, R.G. Ionic liquids based on FeCl3 and FeCl2. raman scattering and ab initio calculations. Inorg. Chem., 2001, 40(10), 2298-2304.
(d) Zhang, Q.; Yang, J.; Lu, X.; Gui, J.; Huang, M. Studies on an ionic liquid based on FeCl3 and its properties. Fluid Phase Equilib., 2004, 226, 207-211.
(e) Lee, S.H.; Ha, S.H.; You, C.Y.; Koo, Y.M. Recovery of magnetic ionic liquid [bmim] FeCl4 using electromagnet. Korean J. Chem. Eng., 2007, 24(3), 436-437.
(b) Tang, S.; Babai, A.; Mudring, A.V. Europium‐based ionic liquids as luminescent soft materials. Angew. Chem. Int. Ed., 2008, 47(40), 7631-7634.
(c) Yoshida, Y.; Saito, G. Influence of structural variations in 1-alkyl-3-methylimidazolium cation and tetrahalogenoferrate (III) anion on the physical properties of the paramagnetic ionic liquids. J. Mater. Chem., 2006, 16(13), 1254-1262.
(b) Raeissi, S.; Peters, C.J. A potential ionic liquid for CO2-separating gas membranes: selection and gas solubility studies. Green Chem., 2009, 11(2), 185-192.
(c) Albo, J.; Santos, E.; Neves, L.A.; Simeonov, S.P.; Afonso, C.A.M.; Crespo, J.G.; Irabien, A. Separation performance of CO2 through supported magnetic ionic liquid membranes (SMILMs). Separ. Purif. Tech., 2012, 97, 26-33.
(d) Ko, N.H.; Lee, J.S.; Huh, E.S.; Lee, H.; Jung, K.D.; Kim, H.S.; Cheong, M. Extractive desulfurization using fe-containing ionic liquids. Energy Fuels, 2008, 22(3), 1687-1690.
(e) Clark, K.D.; Nacham, O.; Yu, H.; Li, T.; Yamsek, M.M.; Ronning, D.R.; Anderson, J.L. Extraction of DNA by magnetic ionic liquids: tunable solvents for rapid and selective DNA analysis. Anal. Chem., 2015, 87(3), 1552-1559.
(b) Bica, K.; Gaertner, P. An Iron-containing ionic liquid as recyclable catalyst for aryl grignard cross-coupling of alkyl halides. Org. Lett., 2006, 8(4), 733-735.
(c) Wanga, H.; Yan, R.; Li, Z.; Zhang, X.; Zhang, S. Fe-containing magnetic ionic liquid as an effective catalyst for the glycolysis of poly(ethylene terephthalate). Catal. Commun., 2010, 11(8), 763-767.
(d) Panja, S.K.; Saha, S. Recyclable, magnetic ionic liquid bmim[FeCl4]-catalyzed, multicomponent, solvent-free, green synthesis of quinazolines. RSC Advances, 2013, 3(34), 14495-14500.
(e) Nguyen, M.D.; Nguyen, L.V.; Jeon, E.H.; Kim, J.H.; Cheong, M.; Sik, K.H.; Lee, J.S. Fe-containing ionic liquids as catalysts for the dimerization of bicyclo[2.2.1]hepta-2,5-diene. J. Catal., 2008, 258(1), 5-13.
(b) Andreani, L.; Lapi, E. Boll. Chim. Farm., 1960, 99, 583.
(c) Zhang, L.; Chen, Z.; Zheng, Q.; Xu, L.; Lei, H.; Yaoxue, B. 1982, 17, 17. Chem. Abstr., 1982, 96, 135383e.
(d) Bonsignore, L.; Loy, G.; Secci, D.; Calignano, A. Synthesis and pharmacological activity of 2-oxo-(2H) 1-benzopyran-3-carboxamide derivatives. Eur. J. Med. Chem., 1993, 28(6), 517-520.
(b) Rong, L.; Li, X.; Wang, H.; Shi, D.; Tu, S.; Zhuang, Q. Efficient synthesis of tetrahydrobenzo[b]pyrans under solvent‐free conditions at room temperature. Synth. Commun., 2006, 36, 2363-2369.
(c) Balalaie, S.; Ahmadi, M.; Bararjanian, M. Tetra-methyl ammonium hydroxide: An efficient and versatile catalyst for the one-pot synthesis of tetrahydrobenzo[b]pyran derivatives in aqueous media. Catal. Commun., 2007, 8(11), 1724-1728.
(d) Balalaie, S.; Bararjanian, M.; Ahmadi, M.; Hekmat, S.; Salehi, P. Diammonium hydrogen phosphate: An efficient and versatile catalyst for the one‐pot synthesis of tetrahydrobenzo[b]pyran derivatives in aqueous media. Synth. Commun., 2007, 37, 1097-1108.
(e) Guo, S.B.; Wang, S.X.; Li, J.T. D,L Proline-catalyzed one-pot synthesis of pyrans and pyrano[2,3-c]pyrazole derivatives by a grinding method under solvent-free conditions. Synth. Commun., 2007, 37, 2111-2120.
(f) Ranu, B.C.; Banerjee, S.; Roy, S. A task specific basic ionic liquid,[bmIm] OH-promoted efficient, green and one-pot synthesis of tetrahydrobenzo [b] pyran derivatives. Indian. Chem, 2008, 47B, 1108-1112.
(g) Lian, X.; Huang, Y.; Li, Y.; Zheng, W. A Green synthesis of tetrahydrobenzo[b]pyran derivatives through three-component condensation using N-methylimidazole as organocatalyst. Monatshefte fur Chemie., 2008, 139(2), 129-131.
(h) Tahmassebi, D.; Bryson, J.; Binz, S. 1,4-Diazabicyclo[2.2.2]octane as an Efficient catalyst for a clean, one-pot synthesis of tetrahydrobenzo[b]pyran derivatives via multicomponent reaction in aqueous media. Synth. Commun., 2011, 41, 2701-2711.
(i)Wang, X.; Shi, D.; Tu, S.; Yao, C. A convenient synthesis of 5-Oxo-5,6,7,8-tetrahydro-4 H -benzo-[b]-pyran derivatives catalyzed by KF-alumina. Synth. Commun., 2003, 33, 119-126.
(j)Hekmatshoar, R.; Majedi, S.; Bakhtiari, K. Sodium selenate catalyzed simple and efficient synthesis of tetrahydro benzo[b]pyran derivatives. Catal. Commun., 2008, 9(2), 307-310.
(k)Seifi, M.; Sheibani, H. High surface area MgO as a highly effective heterogeneous base catalyst for three-component synthesis of tetrahydrobenzopyran and 3,4-dihydropyrano[c]chromene derivatives in aqueous media. Catal. Lett., 2008, 126(3-4), 275-279.
(l)Tabatabaeian, K.; Heidari, H.; Mamaghani, M.; Mahmoodi, N. Ru(II) complexes bearing tertiary phosphine ligands: a novel and efficient homogeneous catalyst for one-pot synthesis of dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyran derivatives. Appl. Organomet. Chem., 2012, 26(2), 56-61.
(m)Fotouhi, L.; Heravi, M.; Fatehi, A.; Bakhtiari, K. Electrogenerated base-promoted synthesis of tetrahydrobenzo[b]pyran derivatives. Tetrahedron Lett., 2007, 48(31), 5379-5381.
(n)Jin, S.; Wang, Q.; Wang, X; Zhang, S.; Li, S. A clean one-pot synthesis of tetrahydrobenzo[b]pyran derivatives catalyzed by hexadecyltrimethyl ammonium bromide in aqueous media. Synlett, 2004, 5, 0871-0873.
(o)Tu, S.; Gao, Y.; Guo, C.; Shi, D.; Lu, Z. A convenient synthesis of 2-amino-5,6,7,8-tetrahydro-5-oxo-4-aryl-7,7-dimethyl-4h-benzo-[b]-pyran-3-carbonitrile under microwave irradiation. Synth. Commun., 2002, 32, 2137-2141.
(p)Banerjee, S.; Saha, A. Free-ZnO nanoparticles: a mild, efficient and reusable catalyst for the one-pot multicomponent synthesis of tetrahydrobenzo[b]pyran and dihydropyrimidone derivatives. New J. Chem., 2013, 37(12), 4170-4175.