G. Nagendra et al. / Tetrahedron Letters 53 (2012) 5059–5063
5063
reaction, the solvent was evaporated and the crude alcohol was extracted into
EtOAc and the organic phase was washed with 5% citric acid (10 mL Â 2), 5%
Na2CO3 (10 mL Â 2), water, and brine solution. The product was isolated after
the evaporation of solvent under reduced pressure and dried over anhydrous
Na2SO4.
27. Kokotos, G.; Noula, C. J. Org. Chem. 1996, 61, 6994.
28. Sureshbabu, V. V.; Sudarshan, N. S.; Muralidhar, L.; Narendra, N. J. Chem. Res.
2007, 683.
29. Fehrentz, J.-A.; Califano, J.-C.; Amblard, M.; Lottet, A.; Martinez, J. Tetrahedron
Lett. 1994, 35, 569.
17. Spectral data for p-tolylmethanol, 2c: Yield 89%; mp 58–60 °C. TLC Rf 0.7
(EtOAc:n-hexane, 1:9). RP-HPLC Rt 21.98 min. 1H NMR (400 MHz, CDCl3):
d = 2.22 (s, 3H), 4.86 (s, 2H), 5.31 (t, 1H), 6.91 (d, 2H), 7.05 (d, 2H) ppm. 13C
NMR (100 MHz, CDCl3): d = 23.1, 67.8, 126.8, 129.1, 138.0, 138.5 ppm. ESI-MS
Calcd for C8H10O m/z 123.1 [M+H]+. Found 123.0.
18. (a) Stanfield, C. F.; Parker, J. E.; Kanellis, P. J. Org. Chem. 1981, 46, 4797; (b)
Thompson, R. C. Methods Enzymol. 1977, 46, 220; (c) Sharma, R. P.; Gore, M. G.;
Akhtar, M. J. Chem. Soc., Chem. Commun. 1979, 875; (d) Ten Brink, R. E. J. Org.
Chem. 1987, 52, 418; (d) Pless, J.; Bauer, W.; Cardenaux, F.; Closse, A.; Hauser,
D.; Huguenia, R.; Roemer, D.; Buescher, H.-H.; Hill, R. C. Helv. Chim. Acta 1979,
62, 398; (e) Shang, L.; Wang, Q.; Fang, H.; Mu, J.; Wang, X.; Yuan, Y.; Wang, B.;
Xu, W. Bioorg. Med. Chem. 2008, 16, 9984; (f) Kokotos, G.; Constantiou-Kokotou,
V. J. Chem. Res. (S) 1992, 391, 3117.
30. (a) Nikawa, J.; Shiba, T. Chem. Lett. 1979, 981; (b) Jadhav, S. V.; Bandyopadhyay,
A.; Benke, S. N.; Mali, S. M.; Gopi, H. N. Org. Biomol. Chem. 2011, 9, 4182; (c)
Papavassilopoulou, E.; Christofis, P.; Terzoglou, D.; Moutevelis-Minakakis, P.
Tetrahedron Lett. 2007, 48, 8323–8325.
31. Falorni, M.; Porcheddu, A.; Taddei, M. Tetrahedron Lett. 1999, 40, 4395–4396.
32. Spectral data for (S)-(9H-fluoren-9-yl)methyl 1-hydroxypropan-2-ylcarbamate,
(Fmoc-L-Ala-ol) 4b: Yield 88%; mp 120–122 °C. TLC Rf 0.5 (EtOAc:n-hexane,
2:8). RP-HPLC Rt 12.39 min. 1H NMR (400 MHz, DMSO-d6): d = 1.02 (d, 3H),
3.17–3.21 (m, 1H), 3.31 (m, 1H), 3.45–3.51 (m, 1H), 4.19 (t, J = 6.3 Hz, 1H), 4.26
(d, J = 7.4 Hz, 2H), 4.63 (t, J = 5.7 Hz, 1H), 7.04 (d, J = 7.8 Hz, 1H), 7.32 (t,
J = 7.4 Hz, 2H), 7.40 (t, J = 7.2 Hz, 2H), 7.69 (d, J = 7.4 Hz, 2H), 7.88 (d, J = 7.4 Hz,
2H) ppm. 13C NMR (100 MHz, DMSO-d6): d = 17.29, 46.74, 48.43, 64.47, 65.14,
120.08, 125.18, 127.02, 127.57, 140.71, 143.94, 155.57 ppm. HRMS Calcd for
19. (a) Cassal, J.-M.; Furst, A.; Meier, W. Helv. Chim. Acta 1976, 59, 1917; (b)
Thaisrivongs, S.; Pals, D. T.; Kati, W. M.; Turner, S. R.; Thosmosco, L. M.; Watt,
W. J. Med. Chem. 1986, 29, 2080.
C
18H19NO3 m/z 320.1263 [M+Na]+. Found 320.1261.
33. Chen, J. J.; Aduda, V. Synth. Commun. 2007, 37, 3493.
34. Spectral data for (S)-(9H-fluoren-9-yl)methyl 4-hydroxybutan-2-ylcarbamate,
20. (a) Bolm, C. Angew. Chem., Int. Ed. 1991, 30, 542; (b) Coppola, G. M.; Schuster, H.
F. Asymmetric Synthesis; John Wiley and Sons: New York, USA, 1987. 85.
21. Wu, S.; Takeya, R.; Eto, M.; Tomizawac J. Pestic Sci. 1987, 12, 221.
22. Martinez, J.; Bali, J. P.; Rodriguez, M.; Castro, B.; Magous, R.; Laur, J.; Lignon, M.
F. J. Med. Chem. 1985, 28, 1874.
23. (a) Boeijen, A.; Ameijde, J. V.; Liskamp, R. M. J. J. Org. Chem. 2001, 66, 8454; (b)
Guichard, G.; Semetey, V.; Didierjean, C.; Aubry, A.; Briand, J. P.; Rodriguez, M. J.
Org. Chem. 1999, 64, 8702.
(Fmoc-c-Ala-ol) 4o: Yield 96%; mp 129–131 °C. TLC Rf 0.3 (EtOAc/n-hexane,
3:7). RP-HPLC Rt 17.69 min. 1H NMR (400 MHz, DMSO-d6): d = 1.24 (d,
J = 6.8 Hz, 3H), 1.55 (m, 2H), 3.41 (m, 2H), 3.73 (m, 1H), 4.11 (t, J = 6.0 Hz,
1H), 4.14–4.24 (m, 3H), 5.18 (br, 1H), 7.28 (t, J = 7.2 Hz, 2H), 7.36 (t, J = 7.6 Hz,
2H), 7.61 (d, J = 5.6 Hz, 2H), 7.84 (d, J = 7.2 Hz, 2H) ppm. 13C NMR (100 MHz,
DMSO-d6): d = 21.13, 37.67, 41.13, 47.27, 58.38, 65.57, 120.54, 125.69, 127.49,
128.50, 141.19, 144.38, 156.11 ppm. HRMS Calcd for C19H21NO3 m/z 334.1419
[M+Na]+. Found 334.1422.
24. Monnee, M. C. F.; Marijne, M. F.; Brouwer, A. J.; Liskamp, R. M. J. Tetrahedron
Lett. 2000, 41, 7991.
35. HPLC particulars: Agilent 1100 series having G1311A VWD at k = 254 nm, flow
0.5 mL/min,
column:
agilent
eclipse
XDB-C18,
pore
size-5 lm,
25. (a) Cho, C. Y.; Morna, E. J.; Cherry, S. R.; Stephans, J. C.; Fodor, S. P.; Adams, C. L.;
Sundaram, A.; Jacobs, J. W.; Schultz, P. G. Science 1993, 261, 1303; (b)
Sureshbabu, V. V.; Sudarshan, N. S.; Venkataramanarao, R. J. Pept. Res. Ther.
2008, 14, 149; (c) Cho, C. Y.; Youngquist, R. S.; Paikoff, S. J.; Baresini, M. H.;
Hebert, A. R.; Berleau, L. T.; Liu, C. W.; Wemmer, D. E.; Keough, T.; Schultz, P. G.
J. Am. Chem. Soc. 1998, 120, 7706.
diameter  length = 4.6  150 mm; method: gradient 0.1% TFA water–
acetonitrile; acetonitrile 30–100% in 30 min.
36. Chiral HPLC particulars: Agilent 1100 series having G1311A VWD at
k = 254 nm, flow 1.0 mL/min, column: phenominex made Lux, pore size-5l,
Cellusole-1, diameter  length = 250  4.6 mm; method: 80:20 n-hexane/
isopropanol in isocratic mode in 40 min.
26. (a) Kokotos, G. Synthesis 1990, 299; (b) Rodriguez, M.; Llinares, M.; Doulut, S.;
Heitz, A.; Martinez, J. Tetrahedron Lett. 1991, 32, 923.