A. Kamal et al. / Tetrahedron: Asymmetry 15 (2004) 935–939
939
4.3.9.
(R)-2-Azido-1-(4-bromophenyl)-1-ethanol
2e.
References and notes
25
D
Yield: 42%; 92% ee (tR ¼ 17:98 min); ½aꢁ )77 (c 1.1,
CHCl3); IR (KBr): 3420, 2100 cmꢀ1
;
1H NMR
1. For reviews, see: (a) McCoull, W.; Davis, F. A. Synthesis
2000, 1347; (b) Osborn, H. M. L.; Sweeney, J. Tetra-
hedron: Asymmetry 1997, 8, 1693; (c) Tanner, D. Angew.
Chem., Int. Ed. 1994, 33, 599.
2. For reviews, see: (a) Bergmeier, S. C. Tetrahedron 2000,
56, 2561; (b) Ager, D. J.; Prakash, I.; Schaad, D. R. Chem.
Rev. 1996, 96, 835.
3. (a) Procopiou, P. A.; Morton, G. E.; Todd, M.; Webb, G.
Tetrahedron: Asymmetry 2001, 12, 2005; (b) Caira, M. R.;
Hunter, R.; Nassimbeni, L. R.; Stevens, A. T. Tetrahe-
dron: Asymmetry 1999, 10, 2175.
4. (a) Luna, A.; Maestro, A.; Astorga, C.; Gotor, V.
Tetrahedron: Asymmetry 1999, 10, 1969; (b) Palmer,
M. J.; Wills, M. Tetrahedron: Asymmetry 1999, 10, 2045;
(c) Tye, H. J. Chem. Soc., Perkin Trans. 1 2000, 275.
5. Crossley, R. Chirality and the Biological Activity of Drugs;
CRC: New York, 1995.
6. (a) Martinez, L. E.; Leighton, J. L.; Carsten, D. H.;
Jacobsen, E. N. J. Am. Chem. Soc. 1995, 117, 5897; (b)
Guy, A.; Dubuffet, T.; Doussot, J.; Godefroy-Falguieres,
A. Synlett 1999, 403; (c) Spelberg, J. H. L.; Vlieg, J. E. T.
H.; Tang, L.; Jansenn, D. B.; Kellog, R. M. Org. Lett.
2001, 3, 41.
7. (a) Watanabe, M.; Murata, K.; Ikaria, T. J. Org. Chem.
2002, 67, 1712; (b) Kamal, A.; Damayanthi, Y.; Rao, M.
V. Indian Patent 2634/DEL/96, 1996; (c) Damayanthi, Y.
Ph.D. thesis, Osmania University, 1998.
(200 MHz, CDCl3): d 2.35 (1H, br s), 3.4 (2H, d,
J ¼ 5.94 Hz), 4.81 (1H, t, J ¼ 5.94 Hz), 7.24 (2H, d,
J ¼ 8.17 Hz), 7.5 (2H, d, J ¼ 8.17 Hz); LSIMS (m=z): 185
(Mþ)57). Anal. Calcd for C8H8BrN3O: C, 39.69; H,
3.33; Br, 33.01; N, 17.36. Found: C, 39.52; H, 3.21; Br,
32.96; N, 17.12.
4.3.10. (S)-2-Azido-1-(4-bromophenyl) ethyl acetate 3e.
25
D
Yield: 44%; >99% ee (tR ¼ 18:52 min); ½aꢁ +93.8 (c
1.1, CHCl3); IR (neat): 2085, 1730 cmꢀ1
;
1H NMR
(200 MHz, CDCl3): d 2.13 (3H, s), 3.35–3.43 (1H, dd,
J ¼ 13.21, 4.15 Hz), 3.53–3.62 (1H, dd, J ¼ 13.21,
7.93 Hz), 5.82 (1H, dd, J ¼ 7.93, 4.15 Hz), 7.2 (2H, d,
J ¼ 8.30 Hz), 7.5 (2H, d, J ¼ 8.30 Hz); LSIMS (m=z): 227
(Mþ)57). Anal. Calcd for C10H10BrN3O2: C, 42.28; H,
3.55; Br, 28.12; N, 14.79. Found: C, 42.13; H, 3.45; Br,
28.03; N, 14.65.
4.3.11. (R)-2-Azido-1-(3-chloro-4-methoxyphenyl)-1-eth-
anol 2f. Yield: 43%; 75% ee [based on acetylated 2f
25
D
(tR ¼ 14:99 min)]; ½aꢁ )66.5 (c 1.2, CHCl3); IR (neat):
3420, 2100 cmꢀ1
;
1H NMR (200 MHz, CDCl3): d 2.3
(1H, br s), 3.36–3.44 (2H, m), 3.9 (3H, s), 4.76 (1H, t,
J ¼ 5.94 Hz), 6.88 (1H, d, J ¼ 8.17 Hz), 7.2 (1H, dd,
J ¼ 8.17, 2.23 Hz), 7.36 (1H, d, J ¼ 2.23 Hz); LSIMS
(m=z): 171 (Mþ)56). Anal. Calcd for C9H10ClN3O2: C,
47.48; H, 4.43; Cl, 15.57; N, 18.46. Found: C, 47.29; H,
4.38; Cl, 15.32; N, 18.28.
8. (a) Yadav, J. S.; Reddy, P. T.; Nanda, S.; Rao, A. B.
Tetrahedron: Asymmetry 2001, 12, 63; (b) Kamal, A.;
Arifuddin, M.; Rao, M. V. Tetrahedron: Asymmetry 1999,
10, 4261.
€
9. (a) Faber, H.; Honig, H.; Wasserthal, P. S. Tetrahedron
Lett. 1988, 29, 1903; (b) Foelsche, E.; Hickel, A.; Honig,
€
H.; Wasserthal, P. S. J. Org. Chem. 1990, 55, 1749; (c)
Brenelli, E. C. S.; Fernandes, J. L. N. Tetrahedron:
Asymmetry 2003, 14, 1255; (d) Pchelka, B. K.; Loupy, A.;
Plenkiewicz, J.; Blanco, L. Tetrahedron: Asymmetry 2000,
€
11, 2719; (e) Pamies, O.; Backvall, J.-E. J. Org. Chem.
2001, 66, 4022.
4.3.12. (S)-2-Azido-1-(3-chloro-4-methoxyphenyl) ethyl
acetate 3f. Yield: 37%; >99% ee (tR ¼ 14:71 min);
25
D
½aꢁ +108.2 (c 1.1, CHCl3); IR (neat): 2085, 1730 cmꢀ1
;
1H NMR (200 MHz, CDCl3): d 2.13 (3H, s), 3.21–3.3
(1H, dd, J ¼ 12.84, 4.15 Hz), 3.53–3.63 (1H, dd,
J ¼ 12.84, 7.93 Hz), 3.9 (3H, s), 5.79 (1H, dd, J ¼ 7.93,
4.15 Hz), 6.87 (1H, d, J ¼ 8.68 Hz), 7.15–7.21 (1H, dd,
J ¼ 8.68, 2.26 Hz), 7.34 (1H, d, J ¼ 2.26 Hz); LSIMS
(m=z): 269 (Mþ). Anal. Calcd for C11H12ClN3O3: C,
48.99; H, 4.48; Cl, 13.15; N, 15.58. Found: C, 48.50; H,
4.35; Cl, 13.05; N, 15.31.
10. (a) Kamal, A.; Sandbhor, M.; Ramana, K. V. Tetrahe-
dron: Asymmetry 2002, 13, 815; (b) Kamal, A.; Sandbhor,
M.; Shaik, A. A.; Sravanthi, V. Tetrahedron: Asymmetry
2003, 14, 2839; (c) Kamal, A.; Sandbhor, M.; Shaik, A. A.
Tetrahedron: Asymmetry 2003, 14, 1575; (d) Kamal, A.;
Sandbhor, M.; Ahmad, K.; Adil, S. F.; Shaik, A. A.
Tetrahedron: Asymmetry 2003, 14, 3861.
11. Pseudomonas cepacia lipases and Pseudomonas fluorescens
(AK-20), were less stereospecific and gave very low
conversion whereas lipozyme immobilized from Mucor
miehei gave no conversion at all. Lipase from Candida
rugosa, Candida antarctica, Porceine pancrease and Can-
dida cylindracea also gave low conversion (10–25%) and
enantioselectivities.
12. Chen, C.-S.; Funjimoto, Y.; Girdaunkar, G.; Sih, C. J.
J. Am. Chem. Soc. 1982, 104, 7294.
13. Reddy, M. A.; Bhanumathi, N.; Rama Rao, K. Chem.
Commun. 2001, 1974.
14. Cho, B. T.; Kang, S. K.; Shin, S. H. Tetrahedron:
Asymmetry 2002, 13, 1209.
Acknowledgements
We are thankful to the Department of Science and
Technology, New Delhi for the financial support for
Grants-in-Aid project under SERC (No. SP/S1/G-47/
99). Three of the authors A.A.S., M.S. and M.S.M. are
thankful to CSIR, New Delhi for the award of a
research fellowship.