Asymmetric Mannich-type reactions of aldimines with a chiral acetate

Organic Letters

Volumn 2, Issue 13, 2000, Pages 1891-1894

  Saito, Susumu ^a   Hatanaka, Keiko ^a   Yamamoto, Hisashi ^a  

^a NAGOYA UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001080997     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol000099e     Document Type: Article

References (38)

1. (a) Evans, D. In Asymmetric Synthesis; Morrison, J. D., Ed.; Academic Press: San diego, CA, 1984; Vol. 3, Chapter 1.
2. (b) Asymmetric Synthesis; Procter, G., Ed.; Oxford University Press: Oxford, 1996; Chapter 5.
3. Ager, D. J.; Prakash, I.; Schaad, D. R. Chem. Rev. 1996, 96, 835.
4. (a) Arend, M.; Westermann, B.; Risch, N. Angew. Chem., Int. Ed. 1998, 37, 1044.
5. (b) Denmark, S. E.; Nicaise, O. J.-C. Chem. Commun. 1996, 999.
6. Risch, N.; Arend, M. In Stereoselective Synthesis (Houben-Weyl), Vol. E21/b; Helmchen, G., Hoffmann, R. W., Mulzer, J., Schaumann, E., Eds.; Thieme: Stuttgart, 1996; p 1833.
7. (a) Most examples concerning the asymmetric Mannich-type reaction employ chiral sources appended to the N atom of aldimines. For leading reviews, see: (a) Hart, D. J.; Ha, D.-C. Chem. Rev. 1989, 89, 1447.
8. (b) Enantioselective Synthesis of β-Amino Acids; Juraisti, E., Ed.; Wiley-VCH: New York, 1997. For recent outstanding examples using chiral aldimines and related reactions, see:
9. Tang, T. P.; Ellman, J. A. J. Org. Chem. 1999, 64, 12.
10. Müller, R.; Goesmann, H.; Waldmann, H. Angew. Chem., Int. Ed. 1999, 38, 184.
11. (e) Davis, F. A.; Szewczyk, J. M.; Reddy, R. E. J. Org. Chem. 1996, 61, 2222. For reactions using chiral metal catalysts, see:
12. (f) Hagiwara, E.; Fujii, A.; Sodeoka, M. J. Am. Chem. Soc. 1998, 120, 2472.
13. (g) Ferraris, D.; Young, B.; Dudding, T.; Lectka, T. J. Am. Chem. Soc. 1998, 120, 4548.
14. (h) Ferraris, D.; Young, B.; Cox, C.; Drury, W. J., III; Dudding, T.; Lectka, T. J. Org. Chem. 1998, 63, 6090.
15. Kobayashi, S.; Ishitani, H.; Ueno, M. J. Am. Chem. Soc. 1998, 120, 431.
16. (j) Ishihara, K.; Miyata, M.; Hattori, K.; Yamamoto, H. J. Am. Chem. Soc. 1994, 116, 10520.
17. For asymmetric Mannich-type reactions using a chiral acetate equivalent (chiral iron acyl complex), see: (a) Liebeskind, L. S.; Welker, M. E.; Fengel, R. W. J. Am. Chem. Soc. 1986, 108, 6328.
18. (b) Liebeskind, L. S.; Welker, M. E.; Goedken, V. J. Am. Chem. Soc. 1984, 106, 441. Very recent example, see:
19. Palomo, C.; Oiarbide, M.; Concepción, M.; González-Rego, C.; Sharma, A. K.; García, M.; González, A.; Landa, C.; Linden, A. Angew. Chem., Int. Ed. 2000, 39, 1063.
20. For preliminary synthesis of 1, see: (a) Saito, S.; Kano, T.; Hatanaka, K.; Yamamoto, H. J. Org. Chem. 1997, 62, 5651. For the more efficient synthesis of 1 we developed recently, see:
21. (b) Saito, S.; Kano, T.; Muto, H.; Nakadai, M.; Yamamoto, H. J. Am. Chem. Soc. 1999, 121, 8943.
22. Saito, S.; Hatanaka, K.; Kano, T.; Yamamoto, H. Angew. Chem., Int. Ed. 1998, 37, 3378.
23. (a) Gluchowski, C.; Cooper, L.; Bergbreiter, D. E.; Newcomb, M. J. Org. Chem. 1980, 45, 3413.
24. (b) Ha, D.-C; Hart, D. J.; Yang, T.-K. J. Am. Chem. Soc. 1984, 106, 4819. The trimethylsilyl ketene acetal of methyl acetate also shows poor reactivity, see:
25. Colvin, E. W.; Macgarry, D. J. Chem. Soc., Chem. Commun. 1985, 539.
26. Colvin, E. W.; Macgarry, D.; Nugent, M. J. Tetrahedron 1988, 44, 4157.
27. In the meantime, restraining effects of the o-methoxyphenyl substituent of aldimines on the formation of β-amino esters, not the β-lactams, was reported in the Refomatsky reaction using α-bromoacetate and Zn, see: Adrian, J. C. Jr.; Barkin, J. L.; Hassib, L. Tetrahedron Lett. 1999, 40, 2457. Moreover, Kobayashi et al. reported a marked influence of aldimines 9 and 17 on the enantioselectivity and reactivity in the Mannich-type reaction using chiral zirconium reagents (ref 3i). Although both aldimines are employable, the reaction mechanism remains totally unclear.
28. 2, see: (a) Uchiyama, M.; Kameda, M.; Mishima, O.; Yokoyama, N.; Koike, M.; Kondo, Y.; Sakamoto, T. J. Am. Chem. Soc. 1998, 120, 4934.
29. For example, the reaction of the aldimine derived from 3-trimethylsilyl-2-propynal with a ketene silyl acetal exhibits reversal in the absolute configuration, compared with that of the aldimine derived from benzaldehyde using a chiral boron reagent. This implies that the (Z)-structure is the reactive form for the former aldimine, whereas it is (E)-isomer for the latter, see ref 3j. In good contrast, the present reaction using the o-anisidine-derived aldimines derived from these two types of aldehydes showed an identical S configuration.
30. See Supporting Information for experimental details.
31. Rasmussen, K. G.; Hazaell, R. G.; Jorgensen, K. A. Chem. Commun. 1997, 1103.
32. (b) Rasmussen, K. G.; Juhl, K.; Hazaell, R. G.; Jorgensen, K. A. J. Chem. Soc., Perkin Trans. 2 1998, 1347.
33. Hasegawa, T.; Yamamoto, H. Synlett 1998, 882. See also ref 6.
34. Bhattarai, K.; Cainelli, G.; Panunzio, M. Synlett 1990, 229.
35. Although it has been reported that aminoester 20 was readily oxidized by CAN to give 22 (ref 8), we were unable to detect the formation of 22 using CAN by varying numerous reaction conditions. No attempt was made here to characterize the exact structure of the dimer. Competitive dimerization is a significant problem in certain cases using CAN, see: Jacob, P., III; Callery, P. S.; Shulgin, A. T.; Castagnoli, N., Jr. J. Org. Chem. 1976, 41, 3627. We also tried oxidative removal of the o-fluorophenyl group from methyl 3-(2-fluorophenyl)amino-3-phenylpropionate (entry 7, Table 1) under conditions similar to those employed for 20 and 21 using CAN. However, product 22 was formed in 14% yield.
36. It was proposed that the boron enolates of α-unsubstituted ketones favor the more stable U-form by 1-2 kcal/mol than the W-form. Similarly, it is conceivable that the bulky phenoxy group of the enolate of 2 renders the U-form most likely and gives a twist-boat transition structure: (a) Gennari, C.; Todeschini, R.; Beretta, M. G.; Favini, G.; Scolastico, C. J. Org. Chem. 1986, 51, 612.
37. (b) Hoffmann, R. W.; Ditrich, K.; Froech, S. Tetrahedron 1985, 41, 5517.
38. Braun, M. Angew. Chem., Int. Ed. Engl. 1987, 26, 24.