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Current Green Chemistry


ISSN (Print): 2213-3461
ISSN (Online): 2213-347X

Review Article

DABCO as a Base and an Organocatalyst in Organic Synthesis: A Review

Author(s): Dinesh K. Jangid*

Volume 7 , Issue 2 , 2020

Page: [146 - 162] Pages: 17

DOI: 10.2174/2213346107666191227101538


One of the organocatalysts 1,4-diazabicyclo[2.2.2]octane (DABCO) is an excellent solid catalyst in a number of reactions. It is also a good nucleophile and a base in numerous reactions for the synthesis of heterocycles. DABCO catalyzes many reactions like cycloaddition reactions, coupling reactions, Baylis-Hillman reaction, Henry reaction, ring opening reactions, etc. One more advanced feature of these reactions is that they proceed through environmental friendly pathway. DABCO has more advantages than other organic catalysts because it is an inexpensive, nontoxic base, an ecofriendly and a highly reactive catalyst for building of organic frameworks, which produce the desired products in excellent yields with high selectivity. Many catalytic applications of DABCO have been reported for the synthesis of an organic framework which has been discussed in this review.

Keywords: 1, 4-diazabicyclo[2.2.2]octane (DABCO), organic transformations, catalysis, environmentally friendly, heck reaction, aryldiazonium tetrafluoroborates.

Graphical Abstract
Yang, H.; Tian, R.; Li, Y. Organic reactions catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO). Front. Chem. China,, 2008, 3(3), 279-287.
Barbier, V.; Couty, F.; David, O.R.P. Morita-Baylis-Hillman reactions with nitroalkenes: A case study. Eur. J. Org. Chem., 2015, 17, 3679-3688.
Ma, G-N.; Jiang, J-J.; Shi, M.; Wei, Y. Recent extensions of the Morita-Baylis-Hillman reaction. Chem. Commun. (Camb.), 2009, 37(37), 5496-5514.
[] [PMID: 19753340]
Zhao, S.; Zhi, H.; Zhang, M.; Yan, Q.; Fan, J.; Guo, J. Morita–Baylis-Hillman reaction in eutectic solvent under aqueous medium. RSC Advances, 2016, 6, 62778-62784.
Yu, Y.Q.; Xu, D.Z. A quaternary ammonium salt [H-DABCO][AcO]: As a recyclable and highly efficient catalyst for the one pot synthesis of β-phosphonomalonates. RSC Advances, 2015, 5, 28857-28863.
Shi, M.; Liu, X.G. Asymmetric Morita-Baylis-Hillman reaction of arylaldehydes with 2-cyclohexen-1-one catalyzed by chiral bis(thio)urea and DABCO. Org. Lett., 2008, 10(6), 1043-1046.
[] [PMID: 18284244]
Jogireddy, R.; Maier, M.E. Synthesis of luminacin D. J. Org. Chem., 2006, 71(18), 6999-7006.
[] [PMID: 16930055]
Wang, H.; Wang, B.; Sun, S.; Cheng, J. Copper-catalyzed radical Heck type cyclization: A three-component reaction of DABCO•(SO2)2, aryldiazonium tetrafluoroborates and dienes toward sulfonated benzo- seven-membered nitrogen heterocycles. Org. Chem. Front., 2018, 5, 2547-2551.
(a)Jadhav, S.N.; Rode, C.V. An efficient palladium catalyzed Mizoroki–Heck cross-coupling in water. Green Chem., 2017, 19, 5958-5970.
(b)Zhao, B.; Shi, Z. Copper-catalyzed intermolecular Heck-like coupling of cyclobutanone oximes initiated by selective C-C bond cleavage. Angew. Chem. Int. Ed. Engl., 2017, 56(41), 12727-12731.
[] [PMID: 28861945]
(a)Li, J-H.; Li, J-L.; Wang, D-P.; Pi, S-F.; Xie, Y-X.; Zhang, M-B.; Hu, X-C. CuI-catalyzed Suzuki-Miyaura and Sonogashira cross-coupling reactions using DABCO as ligand. J. Org. Chem., 2007, 72(6), 2053-2057.
[] [PMID: 17286440]
(b)Meconi, G.M.; Vummaleti, S.V.C.; Luque-Urrutia, J.A.; Belanzoni, P.; Nolan, S.P.; Jacobsen, H.; Cavallo, L. Solà. M.; Poater, A. Mechanism of the Suzuki–Miyaura cross-coupling reaction mediated by [Pd(NHC)(allyl)Cl] precatalysts. Organometallics, 2017, 36(11), 2088-2095.
Hajipour, A.R.; Mohammadsaleh, F. Sonogashira reactions catalyzed by a new and efficient copper (I) catalyst incorporating N-benzyl DABCO chloride. Tetrahedron Lett., 2014, 55, 3459-3462.
Foroughifar, N.; Mobinikhaledi, A.; Rabeie, B.; Jalili, L. DABCO as a mild and efficient catalyst for the synthesis of tetrahydropyrimidines. Rev. Roum. Chim., 2013, 58(6), 491-495.
Behbehani, H.; Ibrahim, H.M. Organocatalysis in heterocyclic synthesis: DABCO as a mild and efficient catalytic system for the synthesis of a novel class of quinazoline, thiazolo [3,2-a]quinazoline and thiazolo[2,3-b] quinazoline derivatives. Chem. Cent. J., 2013, 7(1), 82-99.
[] [PMID: 23651877]
Paliwal, P.; Jetti, S.R.; Bhatewara, A.; Kadre, T.; Jain, S. DABCO catalyzed synthesis of xanthene derivatives in aqueous media. ISRN Org. Chem,, 2013.Article ID 526173 6 pages.
Wu, J.; Sun, X.; Li, Y. DABCO: An efficient organocatalyst in the ring-opening reactions of aziridines with amines or thiols. Eur. J. Org. Chem., 2005, 20, 4271-4275.
Lin, S.; Li, L.; Liang, F.; Liu, Q. DABCO-catalyzed ring opening of activated cyclopropanes and recyclization leading to γ-lactams with an all-carbon quaternary center. Chem. Commun. (Camb.), 2014, 50(72), 10491-10494.
[] [PMID: 25068593]
Wu, J.; Xia, H.G. Tertiary amines as highly efficient catalysts in the ring-opening reactions of epoxides with amines or thiols in H2O: Expeditious approach to β -amino alcohols and β-aminothioethers. Green Chem., 2005, 7, 708-710.
(a)Sartori, G.; Ballini, R.; Bigi, F.; Bosica, G.; Maggi, R.; Righi, P. Protection (and deprotection) of functional groups in organic synthesis by heterogeneous catalysis. Chem. Rev., 2004, 104(1), 199-250.
[] [PMID: 14719975]
(b)Greene, T.W.; Wuts, P.G.M. Protective groups in organic synthesis, 3rd ed; John Wiley: New York, 1999.
Rostami, A.; Pourshiani, O.; Navasi, Y.; Darvishi, N.; Saadati, S. Magnetic nanoparticle-supported DABCO tribromide: A versatile nanocatalyst for the synthesis of quinazolinones and benzimidazoles and protection/deprotection of hydroxyl groups. New J. Chem., 2017, 41, 9033-9040.
Meng, X.B.; Li, Y.F.; Li, Z.J. 1, 4-diazabicyclo[2.2.2]octane (DABCO) as a useful catalyst in organic synthesis. Carbohydr. Res., 2007, 342, 1101-1104.
[] [PMID: 17336949]
Gadakh, B.K.; Patil, P.R.; Malik, S.; Kartha, K.P.R. Novel selectivity in carbohydrate reactions, IV: DABCO mediated regioselective primary hydroxyl protection of carbohydrates. Synth. Commun., 2009, 39, 2430-2438.
Mahdian, S.; Naimi-Jamal, M.R.; Panahi, L. Chemoselective protection of hydroxyl and amine functional groups catalysed by MOFs., 2016.
Munch, H.; Hansen, J.S.; Pittelkow, M.; Christensen, J.B.; Boas, U. A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate. Tetrahedron Lett., 2008, 49, 3117-3119.
Declerck, V.; Ribière, P.; Martinez, J.; Lamaty, F. Sequential aza-Baylis-Hillman/ring closing metathesis/aromatization as a novel route for the synthesis of substituted pyrroles. J. Org. Chem., 2004, 69(24), 8372-8381.
[] [PMID: 15549809]
Kosal, A.D.; Wilson, E.E.; Ashfeld, B.L. Direct acyl substitution of carboxylic acids: A chemoselective O- to N-acyl migration in the traceless Staudinger ligation. Chemistry, 2012, 18(45), 14444-14453.
[] [PMID: 23001688]
Valeur, E.; Bradley, M. Amide bond formation: Beyond the myth of coupling reagents. Chem. Soc. Rev., 2009, 38(2), 606-631.
[] [PMID: 19169468]
Tajbakhsh, M.; Heravi, M.M.; Habibzadeh, S. DABCO–bromine complex: A novel oxidizing agent for oxidative deprotection of THP and silyl ethers and semicarbazones to corresponding carbonyl compounds. Synth. Commun., 2007, 37, 2967-2973.
Heravi, M.M.; Derikvand, F.; Ghassemzadeh, M.; Neumuller, B. Synthesis, characterization and structure of a tetrameric DABCO–bromine complex: A novel oxidizing agent for oxidation of alcohols to carbonyl compounds. Tetrahedron Lett., 2005, 46, 6243-6245.
Crouch, R.D. Selective deprotection of silyl ethers. Tetrahedron, 2013, 69, 2383-2417.
Sharafi, T.; Heravi, M.M. DABCO, A reagent for deprotection of benzylic trimethylsilyl ethers under microwave irradiation in a solventless system. Phosphorus Sulfur Silicon Relat. Elem., 2004, 179, 2437-2440.
Zorn, C.; Gnad, F.; Salmen, S.; Herpin, T.; Reiser, O. Deprotection of N-Alloc amines by Pd (0)/DABCO-an efficient method for in situ peptide coupling of labile amino acids. Tetrahedron Lett., 2001, 42, 7049-7053.
Papageorgiou, C.D.; Ley, S.V.; Gaunt, M.J. Organic-catalyst-mediated cyclopropanation reaction. Angew. Chem. Int. Ed. Engl., 2003, 42(7), 828-831.
[] [PMID: 12596214]
Bremeyer, N.; Smith, S.C.; Ley, S.V.; Gaunt, M.J. An intramolecular organocatalytic cyclopropanation reaction. Angew. Chem. Int. Ed. Engl., 2004, 43(20), 2681-2684.
[] [PMID: 18629989]
Papageorgiou, C.D.; Cubillo de Dios, M.A.; Ley, S.V.; Gaunt, M.J. Enantioselective organocatalytic cyclopropanation via ammonium ylides. Angew. Chem. Int. Ed. Engl., 2004, 43(35), 4641-4644.
[] [PMID: 15352192]
Kimachi, T.; Kinoshita, H.; Kusaka, K.; Takeuchi, Y.; Aoe, M.; Juichi, M. The highly trans-selective darzens reaction via ammonium ylides. Synlett, 2005, 5, 842-844.
Zhao, G-L.; Shi, M. Aza-Baylis-Hillman reactions of N-tosylated aldimines with activated allenes and alkynes in the presence of various Lewis base promoters. J. Org. Chem., 2005, 70(24), 9975-9984.
[] [PMID: 16292830]
Yang, Z.; Fan, M.; Mu, R.; Liu, W.; Liang, Y. A facile synthesis of highly functionalized dihydrofurans based on 1,4-diazabicyclo [2.2.2]octane (DABCO) catalyzed reaction of halides with enones. Tetrahedron, 2005, 61, 9140-9146.
Shi, Y-L.; Shi, M. DABCO-catalyzed reaction of allenic esters and ketones with salicyl N-tosylimines: synthesis of highly functionalized chromenes. Org. Lett., 2005, 7(14), 3057-3060.
[] [PMID: 15987204]
Shi, Y-L.; Shi, M. Synthesis of substituted chromenes through the DABCO-catalyzed reaction of but-3-yn-2-one and methyl propiolate with salicyl N-tosylimines (DABCO = 1, 4-diazabicyclo [2.2.2]octane). Chemistry, 2006, 12(12), 3374-3378.
[] [PMID: 16470561]
Fan, M-J.; Li, G-Q.; Liang, Y-M. DABCO catalyzed reaction of various nucleophiles with activated alkynes leading to the formation of alkenoic acid esters, 1,4-dioxane, morpholine, and piperazinone derivatives. Tetrahedron, 2006, 62(29), 6782-6791.
Fan, M-J.; Li, G-Q.; Li, L-H.; Yang, S-D.; Liang, Y-M. DABCO catalyzed reaction of phenols or 1,2-diphenols with activated alkynes leading to the formation of alkenoic acid esters or 1,3-dioxole derivatives. Synthesis, 2006, 14, 2286-2292.
Pimenta, L.S.; Gusevskaya, E.V.; Alberto, E.E. Intermolecular halogenation/esterification of alkenes with N– halosuccinimide and acetic acid catalyzed by 1,4-diazabicyclo[2.2.2]octane. Adv. Synth. Catal., 2017, 359, 2297-2303.
Jain, S.; Rajguru, D.; Keshwal, B.S.; Acharya, A.D. Solvent-free green and efficient one-pot synthesis of dihydropyrano [3,2-c]chromene derivatives. ISRN Org. Chem., 2013. 2013185120
[] [PMID: 24282643]
Asadolah, K.; Heravi, M.M.; Hekmatshoar, R. Solvent-free DABCO-catalyzed one-pot conversion of tetrahydropyranyl ethers into acetates by the action of bismuth(III) nitrate under microwave irradiation. Russ. J. Org. Chem., 2009, 45, 1110-1111.
Zhang, W.; Xu, H.; Xu, H.; Tang, W. DABCO-catalyzed 1, 4-bromolactonization of conjugated enynes: highly stereoselective formation of a stereogenic center and an axially chiral allene. J. Am. Chem. Soc., 2009, 131(11), 3832-3833.
[] [PMID: 19245198]
Bhagat, U.K. Kamaluddin; Peddinti, R.K. DABCO-ediated aza-Michael addition of 4-aryl-1H-1,2,3-triazoles to cycloalkenones. Regioselective synthesis of disubstituted 1,2,3-triazoles. Tetrahedron Lett., 2017, 58, 298-301.
Ying, A.; Li, Z.; Yang, J.; Liu, S.; Xu, S.; Yan, H.; Wu, C. DABCO-based ionic liquids: recyclable catalysts for aza-Michael addition of α,β-unsaturated amides under solvent-free conditions. J. Org. Chem., 2014, 79(14), 6510-6516.
[] [PMID: 24950008]
(a)Imanzadeh, G.; Ahmadi, F.; Zamanloo, M.; Mansoori, Y. Tetrabutylammonium bromide media aza-Michael addition of 1,2,3,6-tetrahydrophthalimide to symmetrical fumaric esters and acrylic esters under solvent-free conditions. Molecules, 2010, 15(10), 7353-7362.
[] [PMID: 20966877]
(b)Zhu, J-N.; Yang, Z-H.; Qi, M.; Zhao, S-Y. DABCO-catalyzed double cascade cycloaddition of maleimides with bisarylhydrazones: Access to fused pyrazolo[5,1-c][1,2,4]triazole derivatives. Adv. Synth. Catal., 2019, 361, 868-874.
Strasser, S.; Slugovc, C. Nucleophile-mediated oxa-Michael addition reactions of divinyl sulfone – A thiol-free option for step-growth polymerisations. Catal. Sci. Technol., 2015, 5, 5091-5094.
Shi, Y-J.; Humphrey, G.; Maligres, P.E.; Reamer, R.A.; Williams, J.M. Highly regioselective DABCO-catalyzed nucleophilic aromatic substitution (SNAr) reaction of methyl 2,6-dichloronicotinate with phenols. Adv. Synth. Catal., 2006, 348, 309-312.
Hon, Y-S.; Kao, C-Y. DABCO-catalyzed formation of 4-methoxy-1,3-dioxolan-2-ones and their synthetic applications in the aromatic electrophilic substitution. Tetrahedron Lett., 2009, 50, 748-751.
Luque, R.; Macquarrie, D.J. Efficient solvent- and metal-free Sonogashira protocol catalysed by 1,4-diazabicyclo(2.2.2) octane (DABCO). Org. Biomol. Chem., 2009, 7(8), 1627-1632.
[] [PMID: 19343249]
(a)Amer, F.A-K.; Hammouda, M.; El-Ahl, A-A.S.; Abdel-Wahab, B.F. Synthesis of important new pyrrolo[3, 4-c]pyrazoles and pyrazolyl-pyrrolines from heterocyclic beta-ketonitriles. Chin. Chem. Soc., 2007, 54, 1543-1552.
(b)Abdelhamid, A.O.; El-Ghandour, A.H.; El-Reedy, A.A.M. Reactions of hydrazonoyl halides 571: Reactions of 1-bromo-2-(5-chlorobenzofuranyl) ethanedione-1-phenylhydrazone. J. Chin. Chem. Soc. (Taipei), 2008, 55, 406-413.
Sechi, M.; Sannia, L.; Carta, F.; Palomba, M.; Dallocchio, R.; Dessì, A.; Derudas, M.; Zawahir, Z.; Neamati, N. Design of novel bioisosteres of beta-diketo acid inhibitors of HIV-1 integrase. Antivir. Chem. Chemother., 2005, 16(1), 41-61.
[] [PMID: 15739621]
Rapposelli, S.; Lapucci, A.; Minutolo, F.; Orlandini, E.; Ortore, G.; Pinza, M.; Balsamo, A. Synthesis and COX-2 inhibitory properties of N-phenyl- and N-benzyl-substituted amides of 2-(4-methylsulfonylphenyl)cyclopent-1-ene-1-carboxylic acid and of their pyrazole, thiophene and isoxazole analogs. Farmaco, 2004, 59(1), 25-31.
[] [PMID: 14751313]
Siddall, T.L.; Ouse, D.G.; Benko, Z.L.; Garvin, G.M.; Jackson, J.L.; McQuiston, J.M.; Ricks, M.J.; Thibault, T.D.; Turner, J.A.; Vanheertum, J.C.; Weimer, M.R. Synthesis and herbicidal activity of phenyl-substituted benzoylpyrazoles. Pest Manag. Sci., 2002, 58(12), 1175-1186.
[] [PMID: 12476990]
(a)Portela-Cubillo, F.; Scott, J.S.; Walton, J.C. 2-(Aminoaryl)alkanone O-phenyl oximes: Versatile reagents for syntheses of quinazolines. Chem. Commun. (Camb.), 2008, 44(25), 2935-2937.
[] [PMID: 18566730]
(b)Portela-Cubillo, F.; Scott, J.S.; Walton, J.C. Microwave-promoted syntheses of quinazolines and dihydroquinazolines from 2-aminoarylalkanone O-phenyl oximes. J. Org. Chem., 2009, 74(14), 4934-4942.
[] [PMID: 19449842]
(c)Wang, C.; Li, S.; Liu, H.; Jiang, Y.; Fu, H. Copper-catalyzed synthesis of quinazoline derivatives via Ullmann-type coupling and aerobic oxidation. J. Org. Chem., 2010, 75(22), 7936-7938.
[] [PMID: 20964407]
dZhang, J.; Zhu, D.; Yu, C.; Wan, C.; Wang, Z. A simple and efficient approach to the synthesis of 2-phenylquinazolines via sp(3) C-H functionalization. Org. Lett., 2010, 12(12), 2841-2843.
[] [PMID: 20481477]
Vodnala, S.; Bhavani, A.K.D.; Kamutam, R.; Naidu, V.G.M. Promila; Prabhakar, Ch. DABCO-catalyzed one-pot three component synthesis of dihydropyrano[3,2-c]chromene substituted quinazolines and their evaluation towards anticancer activity. Bioorg. Med. Chem. Lett., 2016, 26(16), 3973-3977.
[] [PMID: 27432765]
Peng, Y-Y.; Zeng, Y.; Qiu, G.; Cai, L.; Pike, V.W. A convenient one-pot procedure for the synthesis of 2-aryl quinazolines using active MnO2 as oxidant. J. Heterocycl. Chem., 2010, 47, 1240-1245.
Maheswari, C.U.; Kumar, G.S.; Venkateshwar, M.; Kumar, R.A.; Kantam, M.L.; Reddy, K.R. Highly efficient one‐pot synthesis of 2-substituted quinazolines and 4H-benzo[d][1,3]oxazines via cross dehydrogenative coupling using sodium hypochlorite. Adv. Synth. Catal., 2010, 352, 341.
Yamamoto, H.; Ishihara, K. Lewis Acids in Organic Synthesis. Molecules, 2008.
Jankowska, J.; Paradowska, J.; Rakiel, B.; Mlynarski, J. Iron(II) and zinc(II) complexes with designed pybox ligand for asymmetric aqueous Mukaiyama-aldol reactions. J. Org. Chem., 2007, 72(6), 2228-2231.
[] [PMID: 17315931]
Muthupandi, P.; Sekar, G. Zinc-catalyzed aerobic oxidation of benzoins and its extension to enantioselective oxidation. Tetrahedron Lett., 2011, 52, 692-695.
Mallat, T.; Baiker, A. Oxidation of alcohols with molecular oxygen on solid catalysts. Chem. Rev., 2004, 104(6), 3037-3058.
[] [PMID: 15186187]
Mannam, S.; Alamsetti, S.K.; Sekar, G. Aerobic, chemoselective oxidation of alcohols to carbonyl compounds catalyzed by a DABCO-copper complex under mild conditions. Adv. Synth. Catal., 2007, 349, 2253-2258.
Moghaddam, F.M.; Masoud, N.; Foroushani, B.K.; Saryazdi, S.; Ghonouei, N.; Daemi, E. Silica-supported DABCO -tribromide: A recoverable reagent for oxidation of alcohols to the corresponding carbonyl compounds. Sci. Iran. Trans. C, 2013, 20, 598-602.
Zhang, J.; Tang, Y.; Wei, W.; Wu, Y.; Li, Y.; Zhang, J.; Zheng, Y.; Xu, S. Organocatalytic Cloke−Wilson rearrangement: DABCO-catalyzed ring expansion of cyclopropyl ketones to 2, 3-dihydrofurans. Org. Lett., 2017, 19(12), 3043-3046.
[] [PMID: 28548502]
Rana, N.K.; Shukla, K.; Mahto, P.; Jha, R.K.; Singh, V.K. A facile and highly diastereoselective synthesis of carbocyclic spiro-pyrazolones via DABCO catalyzed Michael-Michael domino reaction. Tetrahedron, 2018, 74, 5270-5279.
Fang, X.; Li, J.; Tao, H-Y.; Wang, C-J. Highly diastereoselective DABCO-catalyzed [3 + 3]-cycloaddition of 1,4-dithiane-2,5-diol with azomethine imines. Org. Lett., 2013, 15(21), 5554-5557.
[] [PMID: 24180687]
Meng, D.; Qiao, Y.; Wang, X.; Wen, W.; Zhao, S. DABCO-catalyzed Knoevenagel condensation of aldehydes with ethyl cyanoacetate using hydroxy ionic liquid as a promoter. RSC Ad., 2018, 8, 30180-30185.
Zhang, J-R.; Liao, Y-Y.; Deng, J-C.; Tang, Z-L.; Xu, Y-L.; Xu, L.; Tang, R-Y. DABCO-promoted decarboxylative acylation: Synthesis of α-Keto and α,β-unsaturated amides or esters. Asian J. Org. Chem., 2017, 6, 305-312.
Kim, H.; Shin, D.; Lee, K.; Lee, S.; Kim, S.; Lee, P.H. Synthesis of (E)-α-ethynyl-α,β-unsaturated esters from allenyl acetates catalyzed by DABCO and their application to Sonogashira cross-coupling reactions. Bull. Korean Chem. Soc., 2010, 31(3), 742-745.
Choe, Y.; Lee, P.H. Stereoselective DABCO-catalyzed synthesis of (E)-α-ethynyl-α, β-unsaturated esters from allenyl acetates. Org. Lett., 2009, 11(6), 1445-1448.
[] [PMID: 19220059]
Soh, L.; Eckelman, M.J. Green solvents in biomass processing. ACS Sustain. Chem.Eng., 2016, 4, 5821-5837.
Bryne, F.P.; Jin, S.; Paggiola, G.; Petchey, T.H.M.; Clark, J.H.; Farmer, T.J.; Hunt, A.J.; McElroy, C.R.; Sherwood, J. Tools and techniques for solvent selection: green solvent selection guides. Sustain. Chem. Process., 2016, 4, 7-31.
Bubalo, M.C.; Vidovic, S.; Redovnikovic, I.R.; Jokic, S. Green solvents for green technologies. J. Chem. Technol. Biotechnol., 2015, 90, 1631-1639.

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