1,2-Additions of Silylenol Ethers to 4-Silyloxy-1-benzothiopyrylium Triflates: A New and Efficient Method for the Synthesis of 2-Substituted Benzothiopyran-4-ones

Synlett

Volumn 1996, Issue 2, 1996, Pages 182-184

  Beifuss, Uwe ^a   Tietze, Mario ^a   Gehm, Henning ^a  

^a UNIVERSITY OF GÖTTINGEN   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0002361539     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1996-5339     Document Type: Article

References (21)

1. Perlmutter, P. Conjugate Addition Reactions in Organic Synthesis; Pergamon: Oxford, 1992.
2. Chapdelaine, M. J.; Hulce, M. Org. React. 1990, 38, 227.
3. (a) Casy, G.; Lane, S.; Taylor, R. J. K. J. Chem. Soc., Perkin Trans. 1 1986, 1397.
4. (b) Lane, S.; Quick, S. J.; Taylor, R. J. K. J. Chem. Soc., Perkin Trans. 1 1985, 893.
5. (c) Batten, R. J.; Coyle, J. D.; Taylor, R. J. K.; Vassiliou, S. J. Chem. Soc., Perkin Trans. 1 1982, 1177.
6. (d) Batten, R. J.; Coyle, J. D.; Taylor, R. J. K. Synthesis 1980, 910.
7. (a) Dieter, R. K.; Silks III, L. A. J. Org. Chem. 1986, 51, 4687.
8. (b) Posner, G. H.; Brunelle, D. J. J. Chem. Soc., Chem. Commun. 1973, 907.
9. (a) Casy, G.; Taylor, R. J. K. Tetrahedron 1989, 45, 455.
10. (b) Clarke, P. D.; Fitton, A. O.; Suschitzky, H.; Wallace, T. W.; Dowlatshahi, H. A.; Suschitzky, J. L. Tetrahedron Lett. 1986, 27, 91.
11. Giles, P. R.; Marson, C. M. Austr. J. Chem. 1992, 45, 439.
12. Simchen, G. In Advances in Silicon Chemistry; Vol. 1; Larson, G. L., Ed.; JAI Press: Greenwich, 1991; p 191.
13. (a) Rücker, C. Chem. Rev. 1995, 95, 1009.
14. (b) Brownbridge, P. Synthesis 1983, 1; 1983, 85.
15. (b) Brownbridge, P. Synthesis 1983, 1; 1983, 85.
16. (c) Colvin, E.W. Silicon in Organic Synthesis; Butterworths: London, 1981.
17. 2 / petroleum ether 3:1) to give the 1,5 diketones 10a-f as colourless oils, which crystallised at -20°C.
18. 3), 2.78 (dd, J = 17.0 Hz, J = 7.0 Hz, 1H, 1′-H), 2.87 (dd, J = 17.0 Hz, J = 7.0 Hz, 1H, 1′-H), 3.91 (q, J = 7.0, Hz, 1 H, 2-H), 5.33 (d, J = 7.0 Hz, 1H, 3-H), 7.10 - 7.26 (m, 3H, arom. H), 7.60 - 7.70 (m, 1H, arom. H).
19. 3), 35.56 (C-2), 45.01 (C-1′), 47.18 (C-3), 125.10 (C-6), 127.73 (C-8), 128.83 (C-5), 130.38 (C-4a), 133.68 (C-7), 140.58 (C-8a), 193.63 (C-4), 204.53 (C-2′).
20. 3): δ = 20.33 (C-4′), 26.11 (C-5′), 38.36 (C-3′), 40.04 (C-2), 42.71 (C-3), 52.44 (C-1′), 125.09 (C-6), 127.52 (C-5), 128.98 (C-8), 130.48 (C-4a), 133.50 (C-7), 141.44 (C-8a), 194.03 (C-4), 216.33 (C-2′).
21. Single crystal X-ray analysis of u-10d was performed by Martina Walker and Regine Herbst-Irmer (Institut für Anorganische Chemie, Universität Göttingen, Tammannstr. 4, D-37077 Göttingen, Germany). Full crystallographic data will be provided in a forthcoming paper.