Functionalization of highly oxygenated xanthones: Unexpected stereochemistry and rearrangements

Synlett

Volumn , Issue 19, 2009, Pages 3187-3191

  Sahin, Hülya ^a   Nieger, Martin ^b   Nising, Carl F ^a   Bräse, Stefan ^a  

^a KARLSRUHE INSTITUTE OF TECHNOLOGY   (Germany)

^b UNIVERSITY OF HELSINKI   (Finland)

Author keywords

Oxidation; Wagner Meerwein rearrangement; Xanthones

Indexed keywords

KETONE DERIVATIVE; XANTHONE DERIVATIVE;

ARTICLE; CHEMICAL STRUCTURE; REACTION ANALYSIS; STEREOCHEMISTRY; WAGNER MEERWEIN REARRANGEMENT;

EID: 72049107795     PISSN: 09365214     EISSN: 14372096     Source Type: Journal    
DOI: 10.1055/s-0029-1218309     Document Type: Article

References (38)

1. (a) Shi, Y.-L.; Shi, M. Org. Biomol. Chem. 2007, 5, 1499.
2. (b) Bräse, S.; Encinas, A.; Keck, J.; Nising, C. F. Chem. Rev. 2009, 109, 3903.
3. (a) Lesch, B.; Bräse, S. Angew. Chem. Int. Ed. 2004, 116, 118;
4. Angew. Chem. 2004, 43, 115.
5. (b) Nising, C. F.; Ohnemüller, U. K.; Friedrich, A.; Lesch, B.; Steiner, J.; Schnöckel, H.; Nieger, M.; Bräse, S. Chem. Eur. J. 2006, 12, 3647.
6. Gérard, E. M. C.; Sahin, H.; Encinas, A.; Bräse, S. Synlett 2008, 2702.
7. (a) Diversonol: Nising, C. F.; Ohnemüller, U. K.; Bräse, S. Angew. Chem. Int. Ed. 2006, 45, 307;
8. Angew. Chem. 2006, 118, 313.
9. (b) For an alternative synthesis, see: Titze, L. F.; Spiegl, D. A.; Stecker, F.; Major, J.; Raith, C.; Große, C. Chem. Eur. J. 2008, 14, 8956.
10. (a) Blennolide: Gérard, E. M. C.; Bräse, S. Chem. Eur. J. 2008, 14, 8089.
11. (b) See also: Nicolaou, K. C.; Li, A. Angew. Chem. Int. Ed. 2008, 47, 6579.
12. Hemisecalonic acid models: Ohnemüller, U. K.; Nising, C. F.; Encinas, A.; Bräse, S. Synthesis 2007, 2175.
13. Otero, H.; Bräse, S. et al., unpublished results.
14. 4 and evaporated under vacuum. The residue was purified by flash column chromatography (cyclohexaneEtOAc, 3:1), yielding 7a (1.77 g, 26%) as a colorless oil.
15. 4, evaporated, and the residue was purified by flash column chromatography (cyclohexane-EtOAc, 3:1), yielding 7a (46 mg, 20%) as a colorless oil.
16. 2 (31.5 mL) and MeCN (6.30 mL) were added NMO (0.560 g, 4.75 mmol, 3.00 equiv) and molecular sieve (1.00 g). After stirring for 30 min TPAP (0.112 g, 0.317 mmol 0.200 equiv) was added and the mixture was refluxed for 2 h. The solvent was evaporated and the residue was purified by flash column chromatography (cyclohexane-EtOAc, 3:1), yielding 7a (0.113 g, 22%) as a colorless oil.
17. 4 and evaporated under vacuum. The residue was purified by flash column chromatography (cyclohexane-EtOAc, 3:1), yielding 7a (93 mg, 40%) as a colorless oil.
18. 4: 232.0736; found: 232.0733.
19. 4: 309.9841; found: 309.9843.
20. 3: 216.0786; found: 216.0788.
21. 2). Hydrogen atoms were localized by difference electron density determination and refined using a riding model [H(O) free]. A semi-absorption correction was applied for 1b and7b.
22. -3.
23. -3.
24. -3.
25. -3.
26. -3. The atoms C9, 09 are disordered [3:1; s.o.f. (C9, H9, O9, H9O) = 0.760(3)].
27. -3. Crystallographic data (excluding structure factors) for the structures reported in this work have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication numbers CCDC 742582 (1b), CCDC 740940 (7a), CCDC 740941 (7b), CCDC 740942 (8a), CCDC 740943 (9a), and CCDC 740944 (11a). Copies of the data can be obtained free of charge on application to: The Director, CCDC, 12 Union Road, Cambridge DB2 IEZ, UK deposit@ccdc.cam.ac.uk
28. For some hydrates of nonactivated, cyclic ketones, see, for example: Khartulyari, A. S.; Maier, M. E. Eur. J. Org. Chem. 2007, 317.
29. (a) Cromwell, N. H.; Bambury, R. E. J. Org. Chem. 1961, 26, 997.
30. (b) Buchanan, G. L.; Jhaveri, D. B. J. Org. Chem. 1961, 26, 4295.
31. Watanabe, H.; Katsuhara, J.; Yamamoto, N. Bull. Chem. Soc. Jpn. 1971, 44, 1328.
32. Rehse, K.; Bienfait, R. Arch. Pharm. 1984, 317, 385.
33. (e) Bach, R. D.; Klix, R. C. Tetrahedron Lett. 1985, 26, 985.
34. (f) Bach, R. D.; Klix, R. C. J. Org. Chem. 1985, 50, 5438.
35. (g) Elings, J. A.; Lempers, H. E. B.; Sheldon, R. A. Eur. J. Org. Chem. 2000, 1905.
36. (h) Majidi, L.; El Idrissi, M. Phys. Chem. News 2003, 9, 122.
37. Singh, V.; Prathap, S. J. Ind. Inst. Sci. 2001, 81, 75.
38. Sheldrick, G. M. Acta Crystallogr., Sect. A 2008, 64, 112.