Chemistry and catalysis advances in organometallic chemistry and catalysis
Three-Component “Click” Reaction
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15.2.3 Three-Component “Click” Reaction Owing to the danger, difficulty in handling, and isolation problems of low molecular weight organic azides [36], a number of methodologies have been developed for the synthesis of 1,4-disubstituted triazoles via [3 + 2] cycloadditions, avoiding the use of preisolated azides. To this end, a series of three-component synthetic methodologies have been used through the one-pot reaction of the terminal alkyne with organic azides generated in situ from sodium azide and an organic bromide [37]. These three-component reactions performed in water are much scarcer. NHC copper(I) complexes [CuBr(SIMes)] (1 in Fig. 15.1) [13a] and [CuCl(SIPr)] (SIPr = N,N-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene, 7 in Scheme 15.9) [38] show high catalytic activity toward the three-component reactions in aqueous media, the latter improving the catalytic performance as a lower catalyst loading is used (2 mol% vs 5 mol%). This reusable ammonium salt-tagged complex turned out to be a highly efficient catalyst involving a wide range of benzyl bromides and terminal alkynes (Scheme 15.9). Analogously, the water-soluble complex containing the tripodal ligand 5 tris(1-benzyl-1H-1,2,3-triazol-4-yl)methanol
·CuCl (see Scheme 15.5), is also able to catalyze the three-component reaction in water but heating and chromatographic purification were required to achieve catalytic efficiency. To date, the most active catalyst for the three-component transformation in water with terminal alkynes is the complex [CuBr(PPh 3 )
], which proceeds under very mild reaction conditions and with the lowest reported catalyst loading (as low as 50 ppm). Good-to-high yields were observed for the corresponding triazoles (no purification step required) after 24 h of reaction [39]. The most versatile catalyst in this three-component transformation is the iminophosphorane copper(I) complex (6), which is also active under very mild reaction conditions (pure water as solvent, at room temperature, and under air conditions) with both terminal and internal 1-iodoalkynes [40]. The latter, is an unprecedented catalytic reaction that is also efficient for a wide array of 1-iodoalkynes and organic bromides (Scheme 15.10). Both electron-withdrawing and electron-donating substituent groups are tolerated, although a longer reaction time is required for the internal iodoalkynes when compared with their terminal counterparts.
Since the very beginning of the discovery of CuAAC, synthetic applications have been extensively used, determining its great popularity among different chemical disciplines. These reactions disclose a type of transformations that are experimentally simple, highly efficient, and reliable, becoming the most genuine examples of Click Chemistry. Although remarkable Scheme 15.9 Ammonium salt-tagged [CuCl(SIPr)]-catalyzed three-component synthesis of triazoles in water. 204 “CLICK” COPPER CATALYZED AZIDE–ALKYNE CYCLOADDITION (CUAAC) IN AQUEOUS MEDIUM Scheme 15.10 Copper catalyzed 1,3-dipolar cycloaddition of in situ generated azides (organic bromide and NaN 3 ) with both terminal and internal 1-iodoalkynes in water. progress has taken place, including new stabilizing ligands and applications of well-defined catalysts, there is still a gap in designing new experimental methodologies and reaction conditions fulfilling strict “Click” criteria. This chapter clarified these features, emphasizing the state of the art of CuAAC in aqueous media known to date, which can allow for a higher number of applications, thus increasing the economic and environmental benefits.
Financial support from the Spanish MICINN (Projects CTQ2010-14796/BQU, CTQ2009-08746/BQU, CTQ2008- 00506/BQU, and CSD2007-00006) is acknowledged. J. G.-A. also thanks MICINN and the European Social Fund for the award of “Juan de la Cierva” and “Ram´on y Cajal” contracts. REFERENCES 1. (a) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless, K. B. Angew. Chem. Int. Ed. 2002, 41 , 2596; (b) Tornøe, C. W.; Christensen, C.; Meldal, M. J. Org. Chem. 2002, 67 , 3057. 2. (a) Huisgen, R. Proc. Chem. Soc. 1961, 357; (b) Huisgen, R.; Knorr, R.; Moebius, L.; Szeimies, G. Chem. Ber. 1965, 98 , 4014; (c) Huisgen, R.; Szeimies, G.; Moebius, L. Chem. Ber. 1967, 100 , 2494; (d) 1,3-Dipolar Cycloaddition Chemistry; Huisgen, R.; Pawda, A., Eds; John Wiley & Sons, Ltd: New York, 1984; Vol. 1 ; (e) Huisgen, R. Pure Appl. Chem. 1989, 61 , 613. 3. 1,5-disubstituted triazoles can be regioselective obtained with ruthenium catalysts. For examples, see: (a) Tam, A.; Arnold, U.; Soellner, M. B.; Raines, R. T. J. Am. Chem. Soc. 2007, 129 , 12670; (b) Boren, B. C.; Narayan, S.; Rasmussen, L. K.; Zhang, L.; Zhao, H.; Lin, Z.; Jia, G.; Fokin, V. V. J. Am. Chem. Soc. 2008, 130 , 8923; (c) Kwok, S. W.; Fotsing, J. R.; Fraser, R. J.; Rodionov, V. O.; Fokin, V. V. Org. Lett., 2010, 12 , 4217; (d) Johansson, J. R.; Lincoln, P.; Nord´en, B.; Kann, N. J. Org. Chem. 2010, 76 , 2355. 4. “Click Chemistry” has found wide application in pharmaceutical, combinatorial, and material chemistry. For selected reviews see: (a) Wu, P.; Fokin, V. V. Aldrichim. Acta 2007, 40 , 7; (b) Spiteri, A. D.; Moses, J. E. ChemMedChem 2008, 3 , 715; (c) Meldal, M.; Tornøe, C. W. Chem. Rev. 2008, 108 , 2952; (d) Holub, J. M.; Kirshenbaum, K. Chem. Soc. Rev. 2010, 39 , 1325. 5. The term “Click chemistry” was coined by K. B. Sharpless et al. in 2001 and describes chemistry tailored to generate substances quickly and reliably by joining small units together. Click chemistry is not a single specific reaction, but was meant to mimic nature, which also generates substances by joining small modular units. Kolb, H. C.; Finn, M. G.; Sharpless, K. B. Angew. Chem. Int. Ed. 2001, 40 , 2004. 6. Baskin, J. M.; Bertozzi, C. R. Aldrichim. Acta 2010, 43 , 15. 7. For recent AgAAC examples see: McNulty, J.; Keska, K. Eur. J. Org. Chem. 2012, 5462. 8. For representative examples see: (a) Rodionov, V. O.; Presolski, S. I.; Gardinier, S.; Lim, Y.-H.; Finn, M. G. J. Am. Chem. Soc. 2007, 129 , 12696; (b) Rodionov, V. O.; Presolski, S. I.; D´ıaz D´ıaz, D.; Fokin, V. V.; Finn, M. G. J. Am. Chem. Soc. 2007, 129 , 12705; (c) Presolski, S. I.; Hong, V.; Cho, S. -H.; Finn, M. G. J. Am. Chem. Soc. 2010, 132 , 14570. 9. See for example: (a) Chan, T. R.; Hilgraf, R.; Sharpless, K. B.; Fokin, V. V. Org. Lett. 2004, 6 , 2853; (b) Lewis, W. G.; Magallon, F. G.; Fokin, V. V.; Finn, M. G. J. Am. Chem. Soc. 2004, 126 , 9152. 10. (a) Liu, Y.; D´ıaz, D. D.; Accurso, A. A.; Sharpless, K. B.; Fokin, V. V.; Finn, M. G. J. Polym. Sci., Part A: Polym. Chem. 2007, 45 , 5182; (b) Isobe, H.; Fujino, T.; Yamazaki, N.; Guillot-Nieckowski, M.; Nakamura, E. Org. Lett. 2008, 10 , 3729. 11. (a) P´erez-Balderas, F.; Ortega-Mu˜noz, M.; Morales-Sanfrutos, J.; Hern´andez-Mateo, F.; Calvo-Flores, F. G.; Calvo-As´ın, J. A.; Isac- Garc´ıa, J.; Santoyo-Gonz´alez, F. Org. Lett. 2003, 5 , 1951; (b) Moitra, N.; Moreau, J. J. E.; Cattoen, X.; Wong Chi Man, M. Chem. Commun. 2010, 46 , 8416. REFERENCES 205 12. [CuBr(PPh 3 )
] and [CuI {P(OEt)}
3 ] complexes have been considered the catalyst of choice for the preparation of glycopolymers, oligomers or more complicated biologically active molecules: (a) Marmuse, L.; Nepogodiev, S. A.; Field, R. A. Org. Biomol. Chem.
Chen, M.; Fang, L. Y.; Sun, D. X.; Wang, P. G. J. Med. Chem. 2008, 51 , 7417; (e) Kato, T.; Miyagawa, A.; Kasuya, M. C. Z.; Hatanaka, K. Open Chem. Biomed. Methods J. 2009, 2 , 13; (f) Papin, C.; Doisneau, G.; Beau, J. M. Chem. Eur. J. 2009, 15 , 53; (g) M´endez-Ardoy, A.; G´omez-Garc´ıa, M.; Ortiz-Mellet, C.; Sevillano, N.; Gir´on, M. D.; Salto, R.; Santoyo-Gonz´alez, F.; Garc´ıa Fern´andez, J. M. Org. Biomol. Chem. 2009, 7 , 2681. 13. (a) D´ıez-Gonz´alez, S.; Correa, A.; Cavallo, L.; Nolan, S. P. Chem. Eur. J. 2006, 12 , 7558; (b) Nolte, C.; Mayer, P.; Straub, B. F. Angew. Chem. Int. Ed. 2007, 46 , 2101; (c) S`everac, M.; Le Pleux, L.; Scarpaci, A.; Blart, E.; Odobel, F. Tetrahedron Lett. 2007, 48 , 6518; (d) D´ıez-Gonz´alez, S.; Nolan, S. P. Angew. Chem. Int. Ed. 2008, 47 , 8881; (e) D´ıez-Gonz´alez, S.; Stevens, E. D.; Nolan, S. P. Chem. Commun. 2008, 4747; (f) Broggi, J.; D´ıez-Gonz´alez, S.; Petersen, J. L.; Berteina-Raboin, S.; Nolan, S. P.; Agrofoglio, L. A. Synthesis 2008, 141; (g) Li, P. H.; Wang, L.; Zhang, Y. C. Tetrahedron 2008, 64 , 10825; (h) Teyssot, M. L.; Chevry, A.; Tra¨ıkia, M.; EI-Ghozzi, M.; Avignant, D.; Gautier, A. Chem. Eur. J. 2009, 15 , 6322; (i) Pawar, G. M.; Bantu, B.; Weckesser, J.; Blechert, S.; Wurst, K.; Buchmeiser, M. R. Dalton Trans. 2009, 9043; (j) D´ıez-Gonz´alez, S.; Escudero-Adan, E. C.; Benet-Buchholz, J.; Stevens, E. D.; Slawin, A. M. Z.; Nolan, S. P. Dalton Trans. 2010, 39 , 7595; (k) Teyssot, M. L.; Nauton, L.; Canet, J. -L.; Cisnetti, F.; Chevry, A.; Gautier, A. Eur. J. Org. Chem. 2010, 3507. 14. (a) Shai, C.; Cheng, G.; Su, D.; Xu, J.; Wang, X.; Hu, Y. Adv. Synth. Catal. 2010, 352 , 1587– 1592; (b) Gonda, Z.; Nov´ak, Z. Dalton
15. For recent reviews on well-defined copper(I) complexes, see: (a) D´ıez-Gonz´alez, S. Catal. Sci. Technol. 2011, 1 , 166; (b) D´ıez- Gonz´alez, S. Curr. Org. Chem. 2012, 15 , 2830. 16. For a review on CuAAC reactions in organic media including mechanistic discussions, see: Hein, J. E.; Fokin, V. V. Chem. Soc. Rev. 2010, 39 , 1302. 17. Cassidy, M. P.; Rauschel, J.; Fokin, V. V. Angew. Chem. Int. Ed. 2006, 45 , 3154. 18. Okzal, E.; ¨ Ozcubukcu, S.; Jimeno, C.; Peric`as, M. Catal. Sci. Technol. 2012, 2 , 195. 19. Rodionov, V. O.; Fokin, V. V.; Finn, M. G. Angew. Chem. Int. Ed. 2005, 44 , 2210. 20. (a) Bai, S. -Q.; Koh, L.; Hor, T. S. A. Inorg. Chem. 2009, 48 , 1207; (b) Li, F.; Hor, T. S. A. Chem. Eur. J. 2009, 15 , 10585. 21. Cho, S. H.; Chang, S. Angew. Chem. Int. Ed. 2007, 46 , 1897. 22. Asano, K.; Matsubara, S. Org. Lett. 2010, 12 , 4988. 23. (a) Wang, F.; Fu, H.; Jiang, Y. Y.; Zhao, Y. F. Adv. Synth. Catal. 2008, 350 1830; (b) Wang, F.; Fu, H.; Jiang, Y. Y.; Zhao, Y. F.
24. Lal, S.; McNally, J.; White, A. J. P.; D´ıez-Gonz´alez, S. Organometallics 2011, 30 , 6225. 25. (a) D´ıez-Gonz´alez, S.; Marion, N.; Nolan, S. P. Chem. Rev. 2009, 109 , 3612; (b) Samojlowicz, C.; Bieniek, M.; Grela, K. Chem.
26. Gaulier, C.; Hospital, A.; Legeret, B.; Delmas, A. F.; Aucagne, V.; Cisnetti, F.; Gautier, A. Chem. Commun. 2012, 48 , 4005. 27. (a) Wu, Y. M.; Deng, J.; Fang, X.; Chen, Q. Y. J. Fluorine Chem. 2004, 125 , 1415; (b) Yan, Z. Y.; Zhao, Y. B.; Fan, M. J.; Liu, W. M.; Liang, Y. M. Tetrahedron 2005, 61 , 9331; For other monodentate amines see: (c) Hasegawa, T.; Umeda, M.; Numata, M.; Fujisawa, T.; Haraguchi, S.; Sakurai, K.; Shinkai, S. Chem. Lett. 2006, 35 , 82; (d) Kalesh, K. A.; Liu, K.; Yao, S. Q. Org. Biomol.
28. ¨
Ozc¸ubukc¸u, S.; Ozkal, E.; Jimeno, C.; Peric`as, M. A. Org. Lett. 2009, 11 , 4680. 29. Garc´ıa- ´ Alvarez, J.; D´ıez, J.; Gimeno, J. Green Chem. 2010, 12 , 2127. 30. (a) Himo, F.; Lovell, T.; Hilgraf, R.; Rostovtsev, V. V.; Noodleman, L.; Sharpless, K. B.; Fokin, V. V. J. Am. Chem. Soc. 2005, 127 , 210; (b) Bock, V. D.; Hiemstra, H.; van Maarseveen, H. Eur. J. Org. Chem. 2006, 51; (c) Buckley, B. R.; Dann, S. E.; Heaney, H.
31. Nevertheless, it has been reported that Cu(I) catalyst [CuBr(SIMes)] and 5 •CuCl can mediate the reaction of benzyl azide and 3-hexyne (see Refs 13a and 28, respectively). 32. However, ruthenium mediated cycloaddition reactions of azides and internal alkynes in organic media have been already reported by Fokin and coworkers. In this case, the Ru-catalyzed triazole annulations proceed through the usual alkyne oligomerization sequence which involves (i) the oxidative coupling of an alkyne and an azide on ruthenium, giving rise to a six-membered ruthenacycle, (ii) subsequent rate-determining reductive elimination, releasing the aromatic triazole product. Zhang, L.; Chen, X.; Xue, P.; Sun, H. H. Y.; Williams, I. D.; Sharpless, K. B.; Fokin, V. V.; Jia, G. J. Am. Chem. Soc. 2005, 127 , 15998. See also Ref. 3b. 33. 5-Bromo and 5-iodotriazoles can be accessible through one-pot cycloaddition/halogenations: (a) Wu, Y.-M.; Deng, J.; Li, Y.; Chen, Q.-Y. Synthesis 2005, 1314; (b) Li, L.; Zhang, G.; Zhu, A.; Zhang, L. J. Org. Chem. 2008, 73 , 3630; (c) Smith, N. W.; Polenz, B. P.; Johnson, S. B.; Dzyuba, S. V. Tetrahedron Lett. 2010, 51 , 550; Also, these 5-halogenated-triazoles can be easily synthesized via cycloaddition of halogenated alkynes: (d) Kuijpers, B. H. M.; Dijkmans, G. C. T.; Groothuys, S.; Quaedflieg, P. J. L. M.; Blaauw, R.
206 “CLICK” COPPER CATALYZED AZIDE–ALKYNE CYCLOADDITION (CUAAC) IN AQUEOUS MEDIUM H.; van Delft, F. L.; Rutjes, F. P. J. T. Synlett 2005, 3059; (e) Hein, J. E.; Tripp, J. C.; Krasnova, L. B.; Sharpless, K. B.; Fokin, V. V. Angew. Chem. Int. Ed. 2009, 48 , 8018; (f) Panteleev, J.; Geyer, K.; Aguilar-Aguilar, A.; Wang, L.; Lautens, M. Org. Lett. 2010, 12 , 5092; (g) Juriˇcek, M.; Stout, K.; Kouwer, P. H. J.; Rowan, A. E. Org. Lett. 2011, 13 , 3494; (h) Bogdan, A.; James, K. Org. Lett. 2011, 13 , 4060; (i) Schwartz, E.; Breitenkamp, K.; Fokin, V. V. Macromolecules 2011, 44 , 4735. 34. 1,4-Disubstituted triazoles can be functionalized through the palladium- or copper-catalyzed direct arylation with arylhalides: (a) Chuprakov, S.; Chernyak, N.; Dudnik, A. S.; Gevorgyan, V. Org. Lett. 2007, 9 , 2333; (b) Basolo, L.; Beccalli, E. M.; Borsini, E.; Broggini, G.; Pellegrino, S. Tetrahedron 2008, 64 , 8182; (c) Ackermann, L.; Potukuchi, H. K.; Landsberg, D.; Vicente, R. Org. Lett. 2008, 10 , 3081; (d) Ackermann, L.; Vicente, R. Org. Lett. 2009, 11 , 4922; Alternatively, 1,4,5-trisubstituted triazoles can be easily synthesized via a dehydrogenative intramolecular coupling recently described by the Ackermann group: (e) Ackermann, L.; Jeyachandran, R.; Potukuchi, H. K.; Nov´ak, P.; B¨uttner, L. Org. Lett. 2010, 12 , 2056. 35. Buckley, B. R.; Dann, S. E.; Heaney, H.; Stubbs, E. C. Eur. J. Org. Chem. 2011, 770. 36. Scriven, E. F. V.; Turnbull, K. Chem. Rev. 1988, 88 , 297. 37. For recent examples in the three-component synthetic methodologies in organic solvents see: (a) Kamijo, S.; Jin, T.; Huo, Z.; Yamamoto, Y. J. Am. Chem. Soc. 2003, 125 , 7786; (b) Kamijo, S.; Jin, T.; Yamamoto, Y. Tetrahedron Lett. 2004, 45 , 689; (c) Kamijo, S.; Jin, T.; Huo, Z.; Yamamoto, Y. J. Org. Chem. 2004, 69 , 2386; (d) Appukkuttan, P.; Dehaen, W.; Fokin, V. V.; Van der Eycken, E. Org. Lett. 2004, 6 , 4223; (e) Kacpraz, K. Synlett 2005, 943; (f) Miao, T.; Wang, L. Synthesis 2008, 363; (g) Yan, Z. -Y.; Wang, L. Synthesis 2010, 447. 38. Wang, W.; Wu, J.; Xia, C.; Li, F. Green Chem. 2011, 13 , 3440. 39. Lal, S.; D´ıez-Gonz´alez, S. J. Org. Chem. 2011, 76 , 2367. 40. Garc´ıa- ´ Alvarez, J.; D´ıez, J.; Gimeno, J.; Su´arez, F. J.; Vincent, C. Eur. J. Inorg. Chem. 2012, 5854. 16 ORGANOGOLD CATALYSIS: HOMOGENEOUS GOLD-CATALYZED TRANSFORMATIONS FOR A GOLDEN JUBILEE Fabien Gagosz Ecole Polytechnique, Laboratoire de Synth`ese Organique (DCSO), Palaiseau, France 16.1 INTRODUCTION After having been ignored by several generations of synthetic chemists for its supposed scarcity, high price, and chemical inertness, gold has been recently reconsidered as a potentially interesting metal for the design of catalysts that might useful in organic synthesis. The birth of gold catalysis in synthetic organic chemistry is generally associated with the elegant work of Ito et al. [1], who reported in 1986 an efficient procedure for the formation of oxazolines by a gold(I)-catalyzed asymmetric addition of an isocyanoacetate to an aldehyde (Scheme 16.1, Eq. 1). However, it should also be noticed that a series of other less common synthetic transformations involving the use of an organogold compound or a gold complex in a stoichiometric amount had been previously described. The formation of biaryls by reaction of an aromatic Grignard reagent in the presence of (CO)AuCl reported in 1930 by Kharasch et al. [2] (Scheme 16.1, Eq. 2), or the formation of ethane from (Ph 3 P)AuMe and iodomethane described by Tamaki and Kochi [3] in 1974 (Scheme 16.1, Eq. 3) are examples of such kinds of transformations. An important breakthrough was made between 1991 and 2000 when Utimoto et al. and Teles et al. first reported that alkynes could be functionalized by an inter- or intramolecular addition of water, alcohols, and amines in the presence of a gold(III) salt or a cationic gold(I) complex (Scheme 16.2, Eqs. 1–3) [4]. This significant advance was followed by the work of Hashmi et al. [5] who demonstrated in 2000 that AuCl 3 could be used as an efficient catalyst for the intramolecular addition of ketones and alcohols to alkynes and for the inter- or intramolecular arylation of alkynes and allenes (Scheme 16.2, Eqs. 4 and 5). These seminal studies definitely set the foundation for the great majority of the developments that have been made so far in the field of homogeneous gold catalysis. After the use of gold in catalysis had been initially considered as a potential “Eldorado” for synthetic chemists [6], a true “gold rush” [7] took place during the last 10 years. The plethora of studies carried out during this period, mainly on the design of new gold catalysts, the exploration of their reactivity, the development of gold-catalyzed transformations, and their applications in synthesis, have established homogeneous gold catalysis as a viable, efficient, and selective tool for modern synthetic chemistry. One of the most striking and early reported examples of the use of homogeneous gold catalysis, which perfectly highlights its interest in synthesis, can be found in the total synthesis of Azadirachtin by Ley et al. Indeed, the synthetic route employed to access the target molecule features an impressive gold-catalyzed Claisen rearrangement that allows the efficient and selective formation of an allenyl ketone from a propargylic enol ether under mild experimental conditions (Scheme 16.3). Advances in Organometallic Chemistry and Catalysis: The Silver/Gold Jubilee International Conference on Organometallic Chemistry Celebratory Book, First Edition. Edited by Armando J. L. Pombeiro. © 2014 John Wiley & Sons, Inc. Published 2014 by John Wiley & Sons, Inc.
208 ORGANOGOLD CATALYSIS: HOMOGENEOUS GOLD-CATALYZED TRANSFORMATIONS FOR A GOLDEN JUBILEE R H
N CO 2 Me C [Au(c-HexNC) 2 ]BF
4 (1 mol%) (1 mol%) CH 2 Cl 2 , rt, 20 h Fe PPh
2 PPh
2 N N R R O N CO 2 Me R R = Me, Et + (1)
MgBr + (CO)AuCl Ar Ar Ar + Au (2) + MeI
+ (3)
(Ph 3 P)Au Me Me Me
(Ph 3 P)AuI Ito et al. [1] Kharasch et al. [2] Tamaki and Kochi [3] 83–100%
Scheme 16.1 Early examples in organogold chemistry. (1) (2)
(3) Utimoto et al. (1991) and Teles et al. (1998) 28–96% R
R 2 MeOH, H 2 O, reflux R 1
2 O R 1 R 2 O R 1 R 2 R 1 R 2 MeO OMe MeO OMe
N R 2 R 1 NaAuCl 4 (2 mol%) NaAuCl 4
CH 3 CN, reflux 85–96% R 1 R 2 NH 2 + 85–96% MeOH, reflux NaAuCl
4 (2 mol%) + or
3 P)AuMe, H 2 SO
MeOH, 55 °C Utimoto et al. (1991) (4) Hashmi et al. (2000) AuCl 3
O HO CH 3 CN, 20
°C O R R O O R R O AuCl 3 (1 mol%) CH 3 CN, 20 °C (5)
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