Experimental
All commercial solvents and reagents were used without further purification except as noted below. THF was distilled from sodium benzophenone ketyl. Analytical thin-layer chromatography (TLC) was carried out on Merck silica gel 60F254 glass plate and column chromatography was performed on Merck silica gel 60 (70-230 mesh). 1H-NMR spectra was obtained using a Bruker Advanced Digital 400 spectrometer. Chemical shifts are reported relative to tetramethylsilane tetramethylsilane peak. MALDI-TOF spectrum was obtained using an Applied Biosystems Voyager-DE STR biospectrometer at NCIRF (Seoul National University).
2MeOH@carceplex 3. To a stirred solution of cavitand 2 (R = heptyl, X = Br, 100 mg) and K2CO3 (106 mg) in THF (1.0 mL) was added thioacetic acid (28.1 mg), and then the mixture was stirred for 2 h at rt. To the reaction mixture was added methanol (1.0 mL) and stirred for 4 h at rt. After stirring for another 24 h, the reaction mixture was neutralized by 2 mL of 1 N HCl. The mixture was partitioned with 10 mL of CH2Cl2 and 10 mL of water. The organic layer was separated and dried over anhydrous MgSO4 and the solvent was removed under reduced pressure. The product was purified by silica gel chromatography with a mixture of CH2Cl2/ Hexane (1:1) as mobile phase (27 mg, 32%): MALDI-TOF MS m/z : 2304 ((carcerand 3 + 2 MeOH + Na+), 100%); 1H NMR (400 MHz, CDCl3) δ 7.03 (s, 8H, Ar-H), 5.86 (d, J = 7.6 Hz, 8H, outer -OCH2O-), 4.70 (t,J = 8.0 Hz, 8H, CH methine), 4.44 (d, J = 7.6 Hz, 8H, inner -OCH2O-), 4.36 (d, J = 12.4 Hz, 8H, outer -CH2SSCH2-), 3.79 (d, J = 13.2 Hz, 8H, inner -CH2SSCH2-), 2.15 (m, 16H, -CH2-), 1.40-1.27 (m, 80H, -(CH2)5-), 0.88 (t, J = 6.8 Hz, 24H, -CH3), -0.30 (m, 6H, encapsulated CH3OH).
References
- (a) Warmuth, R.; Yoon, J. Acc. Chem. Res. 2001, 34, 95. https://doi.org/10.1021/ar980082k
- (b) Ihm, C.; Jo, E.; Kim, J.; Paek, K. Angew. Chem. Int. Ed. 2006, 45, 2056. https://doi.org/10.1002/anie.200503441
- Lee, M. H.; Yang, Z.; Lim, C. W.; Lee, Y. H.; Dongbang, S.; Kang, C.; Kim, J. S. Chem. Rev. 2013, 113, 5071. https://doi.org/10.1021/cr300358b
- (a) Liu, H.; Wang, H.; Yang, W.; Cheng, Y. J. Am. Chem. Soc. 2012, 134, 17680. https://doi.org/10.1021/ja307290j
- (b) Satoh, N.; Yamammoto, K. Org. Lett. 2009, 11(8), 1729. https://doi.org/10.1021/ol900137r
- Hayashida, O.; Ichimura, K.; Sato, D.; Yasunaga, T. J. Org. Chem. 2013, 78, 5463. https://doi.org/10.1021/jo400591w
- (a) Kumprecht, L.; Budesinsky, M.; Vondrasek, J.; Vymetal, J.; Cerny, J.; Cisarova, I.; Brynda, J.; Herzig, V.; Koutnik, P.; Zavada, J.; Kraus, T. J. Org. Chem. 2009, 74, 1082. https://doi.org/10.1021/jo802139s
- (b) Ooya, T.; Choi, S.; Yamashita, A.; Yui, N.; Sugaya, Y.; Kanto, A.; Maruyama, A.; Akita, H.; Ito, R.; Kogure, K.; Harashima, H. J. Am. Chem. Soc. 2006, 128, 3852. https://doi.org/10.1021/ja055868+
- Helgeson, R. C.; Hayden, A. E.; Houk, K. N. J. Org. Chem. 2010, 75, 570. https://doi.org/10.1021/jo9012496
- Sun, J.; Patrick, B. O.; Sherman, J. C. Tetrahedron 2009, 65, 7296. https://doi.org/10.1016/j.tet.2008.11.110
- Han, C. C.; Balakumar, R. Tetrahedron Lett. 2006, 47, 8255. https://doi.org/10.1016/j.tetlet.2006.09.093
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