Stereoselective Cyclopropanation of Chiral Carbohydrate-Derived Enol Ethers

Synlett

Volumn 1996, Issue 11, 1996, Pages 1121-1122

  Schumacher, Ralf ^a   Reissig, Hans Ulrich ^a  

^a DRESDEN UNIVERSITY OF TECHNOLOGY   (Germany)

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[No Author keywords available]

Indexed keywords

EID: 0003781987     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1996-5664     Document Type: Article

References (26)

1. Schumacher, R., Dissertation, Technische Universität Dresden, 1996.
2. th ed., Vol E21c; Helmchen, G.; Hoffmann, R. W.; Mulzer, J.; Schaumann, E., Eds.; Thieme: Stuttgart, 1995; p 3179-3270.
3. (a) Fritschi, H.; Leutenegger, U.; Pfaltz, A. Helv. Chim. Acta 1988, 71, 1553-1565.
4. (b) Müller, D.; Umbricht, G.; Weber, B.; Pfaltz, A. Helv. Chim. Acta 1991, 74, 232-240.
5. (c) Evans, D. A.; Woerpel, K. A.; Hinman, M. M.; Faul, M. M. J. Am. Chem. Soc. 1991, 113, 726-728.
6. (d) Lowenthal, R. E.; Abiko, A.; Masamune, S. Tetrahedron Lett. 1990, 31, 6005-6008.
7. (e) Nishiyama, H.; Itoh, Y.; Matsumoto, H.; Park, S.-B.; Itoh, K. J. Am. Chem. Soc. 1994, 116, 2223-2224.
8. 2 - Further examples for diastereoselective cyclopropanation of glucals: (a) Wienand, A.; Reissig, H.-U. unpublished results, Technische Hochschule Darmstadt, 1991.
9. (b) Kenneth, J. H. Jr.; Fraser-Reid, B. Tetrahedron Lett. 1995, 36, 8901-8904.
10. (c) Hoberg, J. O.; Claffey, D. J. Tetrahedron Lett. 1996, 37, 2533-2536.
11. (d) Timmers, C. M.; Leeuwenburgh, M. A.; Verheijen, J. C.; van der Marel, G. A.; van Boom, J. H. Tetrahedron: Asymmetry 1996, 7, 49-52.
12. Review: Reissig, H.-U. Top. Curr. Chem. 1988, 144, 73-135.
13. Kartha, K. P. R. Tetrahedron Lett. 1986, 27, 3415-3416.
14. Bessodes, M.; Shamsazar, J.; Antonakis, K. Synthesis 1988, 560-562.
15. (a) Taskinen, E.; Liukas, P. Acta Chem. Scand. B 1974, 28, 114-120.
16. (b) Taskinen, E. Tetrahedron 1993, 49, 11389-11394.
17. (c) Scherer, S. diploma thesis, Technische Hochschule Darmstadt, 1992.
18. 1H NMR)] as a colourless oil, which solidified slowly at r.t.
19. All new compounds provided appropiate spectroscopic data and correct elemental analysis.
20. Typical Procedure 2a → 3a (catalyst: copper acetylacetonate): A few drops of a solution of 0.450 g (1.50 mmol) of enol ether 2a and 0.100 g (1.00 mmol) of methyl diazoacetate in 4ml of 1,2-dichloroethane were added at 80°C to a suspension of 0.013 g (0.050 mmol) of copper acetylacetonate in 1 ml of 1,2-dichloroethane. After the reaction had started (evolution of nitrogen), the remaining solution of starting materials was added at 50°C over a period of 5 h via a syringe pump. The reaction mixture was cooled down to r.t. and filtered through a short column (alumina/dichloromethane). Flash chromatography (silicagel, hexane/MeOtBu gradient elution) furnished 0.203 g (54%) of cyclopropane 3a. (catalyst: 5·CuOTf): A mixture of 0.016 g (0.055 mmol) of 5 and 0.012 g (0.050 mmol) of CuOTf in 1 ml of 1,2-dichloroethane was stirred at r.t. for 30 min to give a clear green solution. At r.t. a solution of 0.300 g (1.00 mmol) of enol ether 2a and 0.501 g (5.00 mmol) of methyl diazoacetate in 4 ml of 1,2-dichloroethane was added over a period of 24 h via a syringe pump. Flash chromatography (silicagel, hexane/MeOtBu gradient elution) of the crude product furnished 0.277 g (74%) of cyclopropane 3a.
21. For catalysts of this type see: Aratani, T. Pure Appl. Chem. 1985, 57, 1839-1844. - Brunner, H.; Miehling, W. Monatsh. Chem. 1984, 115, 1237-1254.
22. For catalysts of this type see: Aratani, T. Pure Appl. Chem. 1985, 57, 1839-1844. - Brunner, H.; Miehling, W. Monatsh. Chem. 1984, 115, 1237-1254.
23. Further examples for enantioselective cyclopropanations of silyl enol ethers: Kunz, T.; Reissig, H.-U. Tetrahedron Lett. 1989, 30, 2079-2082. - Dammast, F.; Reissig, H.-U. Chem. Ber. 1993, 126, 2449-2456; ibid. 1993, 126, 2727-2732. - Schumacher, R.; Reissig, H.-U. Liebigs Ann. in press.
24. Further examples for enantioselective cyclopropanations of silyl enol ethers: Kunz, T.; Reissig, H.-U. Tetrahedron Lett. 1989, 30, 2079-2082. - Dammast, F.; Reissig, H.-U. Chem. Ber. 1993, 126, 2449-2456; ibid. 1993, 126, 2727-2732. - Schumacher, R.; Reissig, H.-U. Liebigs Ann. in press.
25. Further examples for enantioselective cyclopropanations of silyl enol ethers: Kunz, T.; Reissig, H.-U. Tetrahedron Lett. 1989, 30, 2079-2082. - Dammast, F.; Reissig, H.-U. Chem. Ber. 1993, 126, 2449-2456; ibid. 1993, 126, 2727-2732. - Schumacher, R.; Reissig, H.-U. Liebigs Ann. in press.
26. Further examples for enantioselective cyclopropanations of silyl enol ethers: Kunz, T.; Reissig, H.-U. Tetrahedron Lett. 1989, 30, 2079-2082. - Dammast, F.; Reissig, H.-U. Chem. Ber. 1993, 126, 2449-2456; ibid. 1993, 126, 2727-2732. - Schumacher, R.; Reissig, H.-U. Liebigs Ann. in press.