New versatile fluorinated chiral building blocks: Synthesis and reactivity of optically pure α-(fluoroalkyl)-β-sulfinylenamines

Journal of Organic Chemistry

Volumn 61, Issue 10, 1996, Pages 3375-3387

  Arnone, Alberto ^a   Bravo, Pierfrancesco ^a   Capelli, Silvia ^a   Fronza, Giovanni ^a   Meille, Stefano V ^a   Zanda, Matteo ^a   Cavicchio, Giancarlo ^a   Crucianelli, Marcello ^a  

^a POLITECNICO DI MILANO   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

3,3,3 TRIFLUOROALANINE; ALANINE DERIVATIVE; ORGANOFLUORINE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHIRALITY; DRUG SYNTHESIS; NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0029971190     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo952097r     Document Type: Article

References (82)

1. For some reviews see: Posner, G. H. In The Chemistry of Sulphones and Sulphoxides; Patai, S., Rappoport, Z., Stirling, C. J. M., Eds.; John Wiley: New York, 1988; p 823. Solladiè, G. In Asymmetric Synthesis; Morrison, J. D., Ed., 1983; Vol. 2, p 157. Barbashyn, M. R., Johnson, C. R. Ibid., Vol. 4, p 227. Posner, G. H. Acc. Chem. Res. 1987, 20, 72.
2. For some reviews see: Posner, G. H. In The Chemistry of Sulphones and Sulphoxides; Patai, S., Rappoport, Z., Stirling, C. J. M., Eds.; John Wiley: New York, 1988; p 823. Solladiè, G. In Asymmetric Synthesis; Morrison, J. D., Ed., 1983; Vol. 2, p 157. Barbashyn, M. R., Johnson, C. R. Ibid., Vol. 4, p 227. Posner, G. H. Acc. Chem. Res. 1987, 20, 72.
3. For some reviews see: Posner, G. H. In The Chemistry of Sulphones and Sulphoxides; Patai, S., Rappoport, Z., Stirling, C. J. M., Eds.; John Wiley: New York, 1988; p 823. Solladiè, G. In Asymmetric Synthesis; Morrison, J. D., Ed., 1983; Vol. 2, p 157. Barbashyn, M. R., Johnson, C. R. Ibid., Vol. 4, p 227. Posner, G. H. Acc. Chem. Res. 1987, 20, 72.
4. For some reviews see: Posner, G. H. In The Chemistry of Sulphones and Sulphoxides; Patai, S., Rappoport, Z., Stirling, C. J. M., Eds.; John Wiley: New York, 1988; p 823. Solladiè, G. In Asymmetric Synthesis; Morrison, J. D., Ed., 1983; Vol. 2, p 157. Barbashyn, M. R., Johnson, C. R. Ibid., Vol. 4, p 227. Posner, G. H. Acc. Chem. Res. 1987, 20, 72.
5. Walker, A. J. Tetrahedron: Asymmetry 1992, 3, 961 and references therein quoted.
6. Bravo, P.; Piovosi, E.; Resnati, G. Synthesis 1986, 579.
7. For the synthesis of chiral fluorinated cyclic alcohols: Arnone, A.; Bravo, P.; Frigerio, M.; Viani, F.; Cavicchio, G.; Crucianelli, M. J. Org. Chem. 1994, 59, 3459. For fluorinated nucleosides: Bravo, P.; Mele, A.; Salani, G.; Viani, F.; La Colla, P. Gazz. Chim. Ital. 1995, 125, 295. For fluoro-oxiranes: Arnone, A.; Bravo, P.; Frigerio, M., Salani, G.; Viani, F.; Zappalà, C. Cavicchio, G.; Crucianelli, M. Tetrahedron 1995, 51, 8289. For the synthesis of optically pure α-trifluoromethyl amino acids: Bravo, P.; Capelli, S.; Meille, S. V.; Viani, F.; Zanda, M.; Kukhar, V. P.; Soloshonok, V. A. Tetrahedron: Asymmetry 1994, 5, 2009.
8. For the synthesis of chiral fluorinated cyclic alcohols: Arnone, A.; Bravo, P.; Frigerio, M.; Viani, F.; Cavicchio, G.; Crucianelli, M. J. Org. Chem. 1994, 59, 3459. For fluorinated nucleosides: Bravo, P.; Mele, A.; Salani, G.; Viani, F.; La Colla, P. Gazz. Chim. Ital. 1995, 125, 295. For fluoro-oxiranes: Arnone, A.; Bravo, P.; Frigerio, M., Salani, G.; Viani, F.; Zappalà, C. Cavicchio, G.; Crucianelli, M. Tetrahedron 1995, 51, 8289. For the synthesis of optically pure α-trifluoromethyl amino acids: Bravo, P.; Capelli, S.; Meille, S. V.; Viani, F.; Zanda, M.; Kukhar, V. P.; Soloshonok, V. A. Tetrahedron: Asymmetry 1994, 5, 2009.
9. For the synthesis of chiral fluorinated cyclic alcohols: Arnone, A.; Bravo, P.; Frigerio, M.; Viani, F.; Cavicchio, G.; Crucianelli, M. J. Org. Chem. 1994, 59, 3459. For fluorinated nucleosides: Bravo, P.; Mele, A.; Salani, G.; Viani, F.; La Colla, P. Gazz. Chim. Ital. 1995, 125, 295. For fluoro-oxiranes: Arnone, A.; Bravo, P.; Frigerio, M., Salani, G.; Viani, F.; Zappalà, C. Cavicchio, G.; Crucianelli, M. Tetrahedron 1995, 51, 8289. For the synthesis of optically pure α-trifluoromethyl amino acids: Bravo, P.; Capelli, S.; Meille, S. V.; Viani, F.; Zanda, M.; Kukhar, V. P.; Soloshonok, V. A. Tetrahedron: Asymmetry 1994, 5, 2009.
10. For the synthesis of chiral fluorinated cyclic alcohols: Arnone, A.; Bravo, P.; Frigerio, M.; Viani, F.; Cavicchio, G.; Crucianelli, M. J. Org. Chem. 1994, 59, 3459. For fluorinated nucleosides: Bravo, P.; Mele, A.; Salani, G.; Viani, F.; La Colla, P. Gazz. Chim. Ital. 1995, 125, 295. For fluoro-oxiranes: Arnone, A.; Bravo, P.; Frigerio, M., Salani, G.; Viani, F.; Zappalà, C. Cavicchio, G.; Crucianelli, M. Tetrahedron 1995, 51, 8289. For the synthesis of optically pure α-trifluoromethyl amino acids: Bravo, P.; Capelli, S.; Meille, S. V.; Viani, F.; Zanda, M.; Kukhar, V. P.; Soloshonok, V. A. Tetrahedron: Asymmetry 1994, 5, 2009.
11. (a) Resnati, G. Tetrahedron 1993, 49, 9385-9445.
12. (b) Banks, R. E.; Tatlow, J. C.; Smart, B. E. Organofluorine Chemistry: Principles and Commercial Applications; Plenum Press: New York, 1994.
13. (c) Welch, J. T.; Eswarakrishnan, S. Fluorine in Bioorganic Chemistry; John Wiley & Son Inc.: New York, 1991.
14. (d) Filler, R.; Kobayashi, Y.; Yagupolskii, L. M. Biomedical Aspects of Fluorine Chemistry; Elsevier: Amsterdam, 1993.
15. (e) Kukhar, V. P.; Soloshonok, V. A. In Fluorine Containing Amino Acids; Kukhar, V. P., Soloshonok, V. A., Eds.; John Wiley & Son Inc.: New York, 1994.
16. (a) McMullen, C. H.; Stirling C. J. J. Chem. Soc. B 1966, 1217. Chan, W.; Lee, A. W. M.; Jiang, L. Tetrahedron Lett. 1995, 36, 715.
17. (a) McMullen, C. H.; Stirling C. J. J. Chem. Soc. B 1966, 1217. Chan, W.; Lee, A. W. M.; Jiang, L. Tetrahedron Lett. 1995, 36, 715.
18. (b) Truce, W E.; Markley, L. D. J Org. Chem. 1970, 35, 3275.
19. (c) Tsuchihashi, G.; Iriuchijima, S.; Maniwa, K. Tetrahedron Lett. 1973, 14, 3389. Yokoyama, M ; Takeshima, T. Tetrahedron Lett. 1978, 19, 147.
20. (c) Tsuchihashi, G.; Iriuchijima, S.; Maniwa, K. Tetrahedron Lett. 1973, 14, 3389. Yokoyama, M ; Takeshima, T. Tetrahedron Lett. 1978, 19, 147.
21. (d) Annunziata, R.; Cinquini, M.; Restelli, A.; Cozzi, F. J. Chem. Soc., Perkin Trans. 1, 1982, 1183. Hua, D. H.; Park, J. G.; Katsuhira, T.; Bharathi, S. N. J. Org. Chem. 1993, 58, 2144. Kawecki, R ; Kozerski, L.; Urbanczyk-Lipkowska, Z.; Bocelli, G. J. Chem Soc., Perkin Trans. 1, 1991, 2255.
22. (d) Annunziata, R.; Cinquini, M.; Restelli, A.; Cozzi, F. J. Chem. Soc., Perkin Trans. 1, 1982, 1183. Hua, D. H.; Park, J. G.; Katsuhira, T.; Bharathi, S. N. J. Org. Chem. 1993, 58, 2144. Kawecki, R ; Kozerski, L.; Urbanczyk-Lipkowska, Z.; Bocelli, G. J. Chem Soc., Perkin Trans. 1, 1991, 2255.
23. (d) Annunziata, R.; Cinquini, M.; Restelli, A.; Cozzi, F. J. Chem. Soc., Perkin Trans. 1, 1982, 1183. Hua, D. H.; Park, J. G.; Katsuhira, T.; Bharathi, S. N. J. Org. Chem. 1993, 58, 2144. Kawecki, R ; Kozerski, L.; Urbanczyk-Lipkowska, Z.; Bocelli, G. J. Chem Soc., Perkin Trans. 1, 1991, 2255.
24. (e) Garcia Ruano, J. L.; Lorente, A.; Rodriguez, J. H. Tetrahedron Lett. 1992, 33, 5637. Baldenius, K. U ; Kagan, H. B. Tetrahedron: Asymmetry 1990, 1, 597. Kawecki, R.; Kozersky, L. Tetrahedron 1986, 42, 1469.
25. (e) Garcia Ruano, J. L.; Lorente, A.; Rodriguez, J. H. Tetrahedron Lett. 1992, 33, 5637. Baldenius, K. U ; Kagan, H. B. Tetrahedron: Asymmetry 1990, 1, 597. Kawecki, R.; Kozersky, L. Tetrahedron 1986, 42, 1469.
26. (e) Garcia Ruano, J. L.; Lorente, A.; Rodriguez, J. H. Tetrahedron Lett. 1992, 33, 5637. Baldenius, K. U ; Kagan, H. B. Tetrahedron: Asymmetry 1990, 1, 597. Kawecki, R.; Kozersky, L. Tetrahedron 1986, 42, 1469.
27. Osipov, S. N.; Kolomiets, A. F.; Fokin, A V. Russ. Chem. Rev. 1992, 61 (8), 798. For a recent report on the preparation of α-(fluoro-and -perfluoroalkyl) imines from the corresponding fluorinated ketones and aldehydes and benzylamine see: Soloshonok, V. A., Kirilenko, A. G.; Kukhar, V. P.; Resnati, G. Tetrahedron Lett. 1994, 35, 3119. In our hands, attempts to obtain the title compounds directly from acid catalyzed condensation of benzylamine and α-(fluoroalkyl)-α′-sulfinyl ketones did not gave satisfactory results.
28. Osipov, S. N.; Kolomiets, A. F.; Fokin, A V. Russ. Chem. Rev. 1992, 61 (8), 798. For a recent report on the preparation of α-(fluoro-and -perfluoroalkyl) imines from the corresponding fluorinated ketones and aldehydes and benzylamine see: Soloshonok, V. A., Kirilenko, A. G.; Kukhar, V. P.; Resnati, G. Tetrahedron Lett. 1994, 35, 3119. In our hands, attempts to obtain the title compounds directly from acid catalyzed condensation of benzylamine and α-(fluoroalkyl)-α′-sulfinyl ketones did not gave satisfactory results.
29. Katritzky, A. R.; Jiang, J. J. Org. Chem. 1994, 59, 4551.
30. Johnson, A. W.; Wong, S. C. K. Can J. Chem., 1966, 44, 2793. For some reviews on the aza-Wittig reaction see: Johnson, A. W.; Kasha, W. C.; Starzewsky, K. A. O.; Dixon, D. A Ylides and Imines of Phosphorus; John Wiley: New York, 1993; Chapt. 13. Molina, P.; Vilaplana, M. J. Synthesis, 1994, 1197 and references cited therein
31. Johnson, A. W.; Wong, S. C. K. Can J. Chem., 1966, 44, 2793. For some reviews on the aza-Wittig reaction see: Johnson, A. W.; Kasha, W. C.; Starzewsky, K. A. O.; Dixon, D. A Ylides and Imines of Phosphorus; John Wiley: New York, 1993; Chapt. 13. Molina, P.; Vilaplana, M. J. Synthesis, 1994, 1197 and references cited therein
32. Johnson, A. W.; Wong, S. C. K. Can J. Chem., 1966, 44, 2793. For some reviews on the aza-Wittig reaction see: Johnson, A. W.; Kasha, W. C.; Starzewsky, K. A. O.; Dixon, D. A Ylides and Imines of Phosphorus; John Wiley: New York, 1993; Chapt. 13. Molina, P.; Vilaplana, M. J. Synthesis, 1994, 1197 and references cited therein
33. For a preliminary report see: Bravo, P.; Crucianelli, M.; Zanda, M. Tetrahedron Lett. 1995, 36, 3043.
34. Kricheldorf, H. R. Synthesis 1972, 695.
35. Kloek, J. A.; Leschinsky, K L. J. Org. Chem. 1978, 43, 1460 and references cited therein.
36. 10 the enol ethers 5c,d were mistaken for E isomers of 3c and 3d. Probably these byproducts do not arise from the corresponding β-sulfinyl enamines, because under aza-Wittig reaction conditions they did not afford the enol ethers 5. It is likely that they are directly produced by reaction of the gem-diols 1c, d with the iminophosphorane 2a.
37. Bravo, P.; Bruché, L.; Crucianelli, M.; Merli, A. J. Fluorine Chem 1995, 74, 127.
38. For a conformational study on β-sulfinyl enamines and α-sulfinylimines see: Kozersky, L.; Kawecki, R.; Hanson, P. E. Magn. Reson Chem., 1994, 32, 517. For a discussion about the intramolecular hydrogen bonding in β-sulfinyl enamines see ref 6d.
39. Oae, S. Organic Sulfur Chemistry: Structure and Mechanism, CRC Press: Boca Raton, 1991; pp 21-26.
40. Erickson, J. A.; Mc Loughlin, J. I. J. Org. Chem. 1995, 60, 1626-1631.
41. The reactions of the β-sulfinyl enamines 3 with acyl halides and anhydrides have a completely different and much more complex outcome, presently not well understood and under active investigation. The results will be reported in due course.
42. Whitesell, J. K. In Comprehensive Organic Synthesis, Trost, B. M , Fleming, I., Eds.; Academic Press. Oxford, 1991; Vol. 6, pp 703-732. Martin, S. F. Ibid , Vol. 2, pp 475-502. Whitesell, J. K.; Whitesell, M. A. Synthesis 1983, 517. Hickmott, P. W. Tetrahedron 1986, 40, 2989.
43. Whitesell, J. K. In Comprehensive Organic Synthesis, Trost, B. M , Fleming, I., Eds.; Academic Press. Oxford, 1991; Vol. 6, pp 703-732. Martin, S. F. Ibid , Vol. 2, pp 475-502. Whitesell, J. K.; Whitesell, M. A. Synthesis 1983, 517. Hickmott, P. W. Tetrahedron 1986, 40, 2989.
44. Whitesell, J. K. In Comprehensive Organic Synthesis, Trost, B. M , Fleming, I., Eds.; Academic Press. Oxford, 1991; Vol. 6, pp 703-732. Martin, S. F. Ibid , Vol. 2, pp 475-502. Whitesell, J. K.; Whitesell, M. A. Synthesis 1983, 517. Hickmott, P. W. Tetrahedron 1986, 40, 2989.
45. Whitesell, J. K. In Comprehensive Organic Synthesis, Trost, B. M , Fleming, I., Eds.; Academic Press. Oxford, 1991; Vol. 6, pp 703-732. Martin, S. F. Ibid , Vol. 2, pp 475-502. Whitesell, J. K.; Whitesell, M. A. Synthesis 1983, 517. Hickmott, P. W. Tetrahedron 1986, 40, 2989.
46. 22 For a recent example of anti-Michael additions of heteroatom nucleophiles see: Back, T. G.; Wehrli, D. Tetrahedron Lett. 1995, 36, 4737 and references therein quoted
47. Bumgardner, C. L.; Bunch, J. E.; Whangbo, M.-H., J. Org. Chem 1986, 51, 4082.
48. Martin, V.; Molines, H.; Wakselman, C. J. Org. Chem., 1992, 57, 5530.
49. There is only one precedent of optically pure aminals like 10, as stated by: Matsumura, Y.; Tomita, T. Tetrahedron Lett., 1994, 35, 3737.
50. For the use of β-sulfinyl amines in the synthesis of alkaloids see Hua and co-workers, ref 6d; see also Pyne, S. G.; Dikic, B. J. Org. Chem., 1990, 55, 1932 and references cited therein. For their use as ligands of transition metals see the works of Kagan, ref 6e. See also: Lim, C. C., Leung, P. H.; Sim, K. Y. Tetrahedron: Asymmetry 1994, 5, 1883.
51. For the use of β-sulfinyl amines in the synthesis of alkaloids see Hua and co-workers, ref 6d; see also Pyne, S. G.; Dikic, B. J. Org. Chem., 1990, 55, 1932 and references cited therein. For their use as ligands of transition metals see the works of Kagan, ref 6e. See also: Lim, C. C., Leung, P. H.; Sim, K. Y. Tetrahedron: Asymmetry 1994, 5, 1883.
52. Carreno, M. C.; Dominguez, E.; Garcia Ruano J. L.; Pedregal, C., Rodriguez, J. H. Tetrahedron 1991, 47, 10035 Hua, D. H. Bharathi, S. N.; Panangadan, J. A. K.; Tsujimoto, A. J. Org. Chem. 1991, 56, 6998.
53. Carreno, M. C.; Dominguez, E.; Garcia Ruano J. L.; Pedregal, C., Rodriguez, J. H. Tetrahedron 1991, 47, 10035 Hua, D. H. Bharathi, S. N.; Panangadan, J. A. K.; Tsujimoto, A. J. Org. Chem. 1991, 56, 6998.
54. Ogura, K.; Tomori, H.; Fujita, M. Chem. Lett. 1991, 1407.
55. Solladiè, G.; Demailly, G.; Greek, C. Tetrahedron Lett., 1985, 26, 435. Pyne, S. G.; Hajipour, A. R. Tetrahedron, 1994, 50, 13501 and references cited therein.
56. Solladiè, G.; Demailly, G.; Greek, C. Tetrahedron Lett., 1985, 26, 435. Pyne, S. G.; Hajipour, A. R. Tetrahedron, 1994, 50, 13501 and references cited therein.
57. Carlsen, P. H. J.; Katsuki, T.; Martin, V. S.; Sharpless, K. B. J. Org. Chem. 1981, 46, 3936. See also: Garner, P.; Park, J. M. J. Org. Chem. 1990, 55, 3772. Casiraghi, G.; Colombo, L.; Rassu, G.; Spanu, P. J Org. Chem. 1991, 56, 6523.
58. Carlsen, P. H. J.; Katsuki, T.; Martin, V. S.; Sharpless, K. B. J. Org. Chem. 1981, 46, 3936. See also: Garner, P.; Park, J. M. J. Org. Chem. 1990, 55, 3772. Casiraghi, G.; Colombo, L.; Rassu, G.; Spanu, P. J Org. Chem. 1991, 56, 6523.
59. Carlsen, P. H. J.; Katsuki, T.; Martin, V. S.; Sharpless, K. B. J. Org. Chem. 1981, 46, 3936. See also: Garner, P.; Park, J. M. J. Org. Chem. 1990, 55, 3772. Casiraghi, G.; Colombo, L.; Rassu, G.; Spanu, P. J Org. Chem. 1991, 56, 6523.
60. Burger, K.; Hoss, E.; Gaa, K.; Sewald, N.; Schierlinger, C. Z. Naturforsch. 1991, B46, 361.
61. 2-catalyzed oxidation and of hydrogenolysis have not been optimized.
62. The formation of acylaminosulfonium ions as intermediates of Pummerer rearrangement has been already proposed: Kita, Y.; Shibata, N.; Kawano, N.; Tohjo, T.; Fujimori, C.; Matsumoto, K.; Fujima, S. J. Chem. Soc., Perkin Trans. 1 1995, 2405, and references cited therein. For a four membered acylaminosulfonium ion see: Yamamoto, K.; Yamazaki, S.; Murata, I.; Fukazawa, Y. J. Org. Chem. 1987, 52, 5239.
63. The formation of acylaminosulfonium ions as intermediates of Pummerer rearrangement has been already proposed: Kita, Y.; Shibata, N.; Kawano, N.; Tohjo, T.; Fujimori, C.; Matsumoto, K.; Fujima, S. J. Chem. Soc., Perkin Trans. 1 1995, 2405, and references cited therein. For a four membered acylaminosulfonium ion see: Yamamoto, K.; Yamazaki, S.; Murata, I.; Fukazawa, Y. J. Org. Chem. 1987, 52, 5239.
64. This unusual nonoxidative pathway is probably general for TFAA-promoted Pummerer rearrangement of N-Cbz 1,1,1-trifluoro-3-sulfinyl amines as shown in the preliminary report: Arnone, A.; Bravo, P.; Bruché, L.; Crucianelli, M.; Vichi, L.; Zanda, M. Tetrahedron Lett. 1995, 36, 7301.
65. A similar outcome was reported for various alkyl o-carbamoylphenyl sulfoxides, which afforded 1,2-benzisothiazole derivatives upon treatment with Lewis acids: Uchida, Y.; Oae, S. Gazz. Chim. Ital., 1987, 117, 649. See also: Wright, S. W.; Abelman, M. M ; Bostrom, L. L.; Corbett, L. L. Tetrahedron Lett. 1992, 33, 153. For a nonoxidative Pummerer rearrangement producing β-lactams see: Kaneko, T. J. Am. Chem Soc. 1985, 107, 5490.
66. A similar outcome was reported for various alkyl o-carbamoylphenyl sulfoxides, which afforded 1,2-benzisothiazole derivatives upon treatment with Lewis acids: Uchida, Y.; Oae, S. Gazz. Chim. Ital., 1987, 117, 649. See also: Wright, S. W.; Abelman, M. M ; Bostrom, L. L.; Corbett, L. L. Tetrahedron Lett. 1992, 33, 153. For a nonoxidative Pummerer rearrangement producing β-lactams see: Kaneko, T. J. Am. Chem Soc. 1985, 107, 5490.
67. A similar outcome was reported for various alkyl o-carbamoylphenyl sulfoxides, which afforded 1,2-benzisothiazole derivatives upon treatment with Lewis acids: Uchida, Y.; Oae, S. Gazz. Chim. Ital., 1987, 117, 649. See also: Wright, S. W.; Abelman, M. M ; Bostrom, L. L.; Corbett, L. L. Tetrahedron Lett. 1992, 33, 153. For a nonoxidative Pummerer rearrangement producing β-lactams see: Kaneko, T. J. Am. Chem Soc. 1985, 107, 5490.
68. See ref 16, pp 18-21.
69. In this case, the deuteration degree in the 3 position was kept at 75%, in order to better detect any change in the labeling degree during the process.
70. For optically pure 1-(trifluoromethyl)ethylamine see: (a) Tarnow, H.; Baasner, B.; Luerssen, K.; Santel, H. J.; Schmidt, R. R. Ger. Offen. DE 3900300 A1 900712, 1990, Chem. Abstr. 113, 212024. (b) Tarnow, H.; Baasner, B.; Homeyer, B.; Hartwig, J. Eur. Pat. Appl., EP 323637 A1 890712, 1990, Chem. Abstr. 112, 98219.
71. For optically pure 1-(trifluoromethyl)ethylamine see: (a) Tarnow, H.; Baasner, B.; Luerssen, K.; Santel, H. J.; Schmidt, R. R. Ger. Offen. DE 3900300 A1 900712, 1990, Chem. Abstr. 113, 212024. (b) Tarnow, H.; Baasner, B.; Homeyer, B.; Hartwig, J. Eur. Pat. Appl., EP 323637 A1 890712, 1990, Chem. Abstr. 112, 98219.
72. The unfluorinated naturally occurring analogue is contained in ergonovine (D-lysergic acid L-1-hydroxy-2-propylamide), an important ergot alkaloid with therapeutic applications.
73. Very recently Uneyama and co-workers reported an interesting approach to enantioenriched (R)-3,3,3-trifluoroalanine (ee 62%) by enantioselective reduction of N-aryl imines of 3,3,3-trifluoropyruvic esters: Sakai, T.; Yan, F.; Uneyama, K. Synlett 1995, 753.
74. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
75. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
76. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
77. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
78. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
79. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
80. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
81. Wang, E. A., Walsh, C. Biochemistry 1981, 20, 7539. Laske, R.; Schoenenberger, H.; Holler, E. Arch. Pharm. 1989, 322, 857. Faraci, W. S.; Walsh, C. T. Biochemistry, 1989, 28, 431. Liger, D.; Blanot, D.; Van Heijenoort, J. FEMS Microbiol. Lett., 1991, 80, 111. Laber, H. Gerbling, K.-P.; Harde, C.; Neff, K.-H.; Verdhoff, E.; Pohlenz, H.-D. Biochemistry, 1994, 33, 3413. Silverman, R. B.; Abeles, R. H. Biochemistry, 1976, 15, 4718. Silverman, R. B.; Abeles, R. H. Biochemistry, 1977, 16, 5515. Wang, E. A.; Kallen, R.; Walsh, C. J. Biol Chem., 1981, 256, 6917.
82. s)-15a with the Cambridge Crystallographic Data Centre. The coordinates can be obtained, on request, from the Director, Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, CB2 1EZ, UK.