1996
N. A. Salvi, S. Chattopadhyay / Tetrahedron: Asymmetry 19 (2008) 1992–1997
4.32. (R)-MTPA ester of 2i
4.43. (R)-MTPA ester of 4e
1H NMR: d 1.55 and 1.61 (two d, J = 6.6 Hz, 3H), 3.48 and 3.58
(two s, 3H), 6.02 (q, J = 6.6 Hz, 1H), 7.16–7.27 (m, 2H), 7.34–7.48
(7H).
1H NMR: d 0.91 and 0.97 (two t, J = 7.2 Hz, 3H), 1.84–2.24 (m,
2H), 3.45 and 3.57 (two s, 3H), 5.86 (t, J = 6.8 Hz, 1H), 7.17–7.28
(m, 3H), 7.31–7.45 (m, 6H).
4.44. (R)-MTPA ester of 4f
4.33. (R)-MTPA ester of 2k
1H NMR: d 0.85 and 0.92 (two t, J = 7.2 Hz, 3H), 1.74–2.02 (m,
2H), 3.45 and 3.56 (two s, 3H), 5.75 (t, J = 7.2 Hz, 1H), 7.06–7.36
(m, 9H).
1H NMR: d 1.59 (d, J = 6.6 Hz, 3H), 3.48 and 3.58 (two s, 3H),
6.39 (q, J = 6.6 Hz, 1H), 7.03–7.12 (m, 2H), 7.26–7.49 (m, 6H).
4.34. (R)-MTPA ester of 2l
4.45. (R)-MTPA ester of 4g
1H NMR: d 1.59 (d, J = 6.6 Hz, 3H), 3.47 and 3.58 (two s, 3H),
6.35 (q, J = 6.6 Hz, 1H), 6.95 (d, J = 8.4 Hz, 1H), 7.22 (d, J = 8.4 Hz,
1H), 7.29–7.44 (m, 5H).
1H NMR: d 0.92 (t, J = 7.2 Hz, 3H), 1.76–2.07 (m, 2H), 3.47 and
3.54 (two s, 3H), 5.78 (t, J = 6.8 Hz, 1H), 7.13 (d, J = 8.4 Hz, 2H),
7.27 (d, J = 8.4 Hz, 2H), 7.31–7.39 (m, 5H).
4.35. (R)-MTPA ester of 2m
4.46. (R)-MTPA ester of 4h
1H NMR: d 1.55 and 1.59 (two d, J = 6.2 Hz, 3H), 2.37 (s, 3H),
3.57 (s, 3H), 6.28 (q, J = 6.2 Hz, 1 H), 7.05–7.18 (m, 1H), 7.22–7.32
(m, 7H), 7.35–7.42 (m, 1H).
1H NMR: d 0.92 (t, J = 7.0 Hz, 3H), 1.82–2.36 (m, 2H), 3.54 (s,
3H), 5.89 (t, J = 6.6 Hz, 1H), 7.11–7.25 (m, 2H), 7.29–7.42 (m, 7H).
4.47. (R)-MTPA ester of 4i
4.36. (R)-MTPA ester of 2n
1H NMR: d 0.89 and 0.94 (two t, J = 6.8 Hz, 3H), 1.86–1.97 (m,
2H), 3.46 and 3.58 (two s, 3H), 5.75 (t, J = 6.4 Hz, 1H), 7.15–7.21
(m, 2H), 7.27–7.45 (m, 7H).
1H NMR: d 1.57 and 1.59 (two d, J = 7.2 Hz, 3 H), 2.29 (s, 3H),
3.47 and 3.57 (two s, 3H), 6.04 (q, J = 7.2 Hz, 1H), 7.00–7.42 (m,
9H).
4.48. (R)-MTPA ester of 4j
4.37. (R)-MTPA ester of 2o
1H NMR: d 0.93 (t, J = 7.2 Hz, 3H), 1.76–2.06 (m, 2H), 3.47 and
3.58 (two s, 3H), 5.77 (t, J = 6.6 Hz, 1H), 7.08 (d, J = 8.4 Hz, 2H),
7.30–7.50 (7H).
1H NMR: d 1.57 and 1.59 (two d, J = 7.0 Hz, 3H), 2.31 (s, 3H), 3.46
and 3.56 (two s, 3H), 6.08 (q, J = 7.0 Hz, 1 H), 6.88–7.02 (m, 2H),
7.22–7.28 (m, 5H), 7.38–7.50 (m, 2H).
4.49. (R)-MTPA ester of 4k
1H NMR: d 0.96 (t, J = 7.0 Hz, 3H), 1.82–1.93 (m, 2H), 3.49 and
3.57 (two s, 3H), 6.20 (t, J = 6.4 Hz, 1H), 6.93 (d, J = 8.4 Hz, 1H),
7.09 (dd, J = 8.4, 2.0 Hz, 1H), 7.25 (s, 1H), 7.37–7.41 (m, 5H).
4.38. (R)-MTPA ester of 2p
1H NMR: d 1.59–1.69 (two overlapping d, 3H), 3.47 and 3.58
(two s, 3H), 6.16 (q, J = 6.4 Hz, 1H), 7.30–7.78 (m, 7H), 8.06–8.20
(m, 2H).
References
4.39. (R)-MTPA ester of 2q
1. (a) Asymmetric Synthesis; Morrison, J. D., Ed.; Academic Press: NY, 1983; Vol. 2,
Chapter 2; (b) Singh, V. K. Synthesis 1992, 605–617; (c) Fujii, A.; Hashiguchi, S.;
Uematsu, N.; Ikariya, T.; Noyori, R. J. Am. Chem. Soc. 1996, 118, 2521–2522.
2. Food & Drug Administration Chirality 1992, 4, 338–340.
1H NMR: d 1.50 and 1.62 (two d, J = 6.6 Hz, 3H), 3.47 and 3.57
(two s, 3H), 6.12 (q, J = 6.6 Hz, 1H), 7.25–7.69 (m, 7H), 8.12–8.32
(m, 2H).
3. (a) Schnell, B.; Faber, K.; Kroutil, W. Adv. Synth. Catal. 2003, 345, 653–666; (b)
Zak, A. Curr. Opin. Chem. Biol. 2001, 5, 130–136; (c) Patel, R. N. In Stereoselective
Biocatalysis; Patel, R. N., Ed.; Mercel Dekker: New York, 2000; pp 87–130.
4. (a) Jones, J. B.; Beck, J. F. In Application of Biochemical Systems in Organic
Chemistry. Part I; Jones, J. B., Shi, C. J., Perlman, D., Eds.; Wiley: NY, 1976; Vol. X,
pp 236–401; (b) Davies, H. G.; Green, R. H.; Kelly, D. R.; Roberts, S. M. In
Biotransformations in Preparative Organic Chemistry. The Use of Isolated Enzymes
and Whole Cell Systems in Synthesis; Academic Press: London, 1989; Chapter 3;
(c) Azerad, R.; Buisson, D. In Microbial Reagents in Organic Synthesis; Servi, S.,
Ed.; Kluwer Academic: Dordecht, The Netherlands, 1992; pp 421–440; (d)
Roberts, S. M.; Turner, A. J.; Willetts, A. J.; Turner, M. K. Introduction to
Biocatalysis using Enzymes and Microorganisms; Cambridge University Press: NY,
1995; (e) Faber, K. Biotransformations in Organic Chemistry, 2nd ed.; Springer:
Berlin, 1995.
4.40. (R)-MTPA ester of 4b
1H NMR: d 0.91 and 0.95 (two t, J = 7.2 Hz, 3H), 1.79–2.27 (m,
2H), 3.44 and 3.56 (two s, 3H), 6.16 (t, J = 6.8 Hz, 1H), 6.99–7.21
(m, 3H), 7.28–7.47 (m, 6H).
4.41. (R)-MTPA ester of 4c
1H NMR: d 0.85 and 0.93 (two t, J = 7.2 Hz, 3H), 1.78–2.31 (m,
2H), 3.47 and 3.57 (two s, 3H), 5.80 (t, J = 7.0 Hz, 1H), 6.85–6.89
(m, 1H), 6.94–7.02 (m, 3H), 7.21–7.40 (m, 5H).
5. (a) Salvi, N. A.; Patil, P. N.; Udupa, S. R.; Banerji, A. Tetrahedron: Asymmetry
1995, 6, 2287–2290; (b) Salvi, N. A.; Udupa, S. R.; Banerji, A. Biotechnol. Lett.
1998, 20, 201–203; (c) Salvi, N. A.; Chattopadhyay, S. Tetrahedron 2002, 57,
2833–2839; (d) Salvi, N. A.; Badheka, L. P.; Chattopadhyay, S. Biotechnol. Lett.
2003, 25, 1081–1086; (e) Salvi, N. A.; Chattopadhyay, S. Tetrahedron:
Asymmetry 2004, 15, 3397–3400; (f) Salvi, N. A.; Chattopadhyay, S. Bioorg.
Med. Chem. 2006, 14, 4918–4922.
4.42. (R)-MTPA ester of 4d
6. (a) Ito, Y.; Hayashi, T. Japan, Kokai Tokyo, Koho JP 02, 264 736, (Chem. Abstr.
1991, 114, 124856e); (b) Chen, C.; Prasad, K.; Repic, O. Tetrahedron Lett. 1991,
32, 7175–7178; (c) Yadav, J. A.; Reddy, P. T.; Nanda, S.; Bhasker Rao, A.
Tetrahedron: Asymmetry 2001, 12, 3381–3385; (d) Schenk, D.; Games, D.;
Seubert, P. J. Mol. Neurosci 2001, 17, 259–265; (e) Rotella, D. P. Chemtracts 2000,
1H NMR: d 0.92 (t, J = 7.2 Hz, 3H), 1.80–2.04 (m, 2H), 3.48 and
3.55 (two s, 3H), 5.80 (t, J = 7.2 Hz, 1H), 6.93–7.02 (m, 2H), 7.16–
7.22 (m, 2H), 7.26–7.34 (m, 5H).