Synthesis of 2-oxazolones and α-aminoketones via palladium-catalyzed reaction of β,β-dibromoenamides

Organic Letters

Volumn 13, Issue 1, 2011, Pages 106-109

  Chai, David I ^a   Hoffmeister, Laura ^a   Lautens, Mark ^a  

^a UNIVERSITY OF TORONTO   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 78650856225     PISSN: 15237060     EISSN: 15237052     Source Type: Journal    
DOI: 10.1021/ol102634c     Document Type: Article

References (29)

1. Fang, Y.-Q.; Lautens, M. Org. Lett. 2005, 7, 3549
2. Fang, Y.-Q.; Yuen, J.; Lautens, M. J. Org. Chem. 2007, 72, 5152
3. Sun, C.; Xu, B. J. Org. Chem. 2008, 73, 7361
4. Viera, T. O.; Meaney, L. A.; Shi, Y.-L.; Alper, H. Org. Lett. 2008, 10, 4899
5. Arthuls, M.; Pontikis, R.; Florent, J.-C. Org. Lett. 2009, 11, 4608
6. Bryan, C. S.; Braunger, J. A.; Lautens, M. Angew. Chem. Int. Ed. 2009, 48, 7064
7. Chai, D.; Lautens, M. J. Org. Chem. 2009, 74, 3054, and references therein.
8. Newman, S. G.; Lautens, M. J. Am. Chem. Soc. 2010, 132, 11416
9. For other coupling reactions of dibromides, see: Evano, G.; Coste, A.; Jouvin, K. Angew. Chem., Int. Ed. 2010, 49, 2840 and references cited therein
10. Berciano, B. P.; Lebrequier, S.; Besselièvre, F.; Piguel, S. Org. Lett. 2010, 12, 4038
11. Xu, H.; Zhang, Y.; Huang, J.; Chen, W. Org. Lett. 2010, 12, 3704
12. Faulkner, D. J. Nat. Prod. Rep. 1999, 16, 155
13. Cacchi, S.; Fabrizi, G. Chem. Rev. 2005, 105, 2873
14. Luo, J.-K.; Federspiel, R. F.; Castle, R. N. J. Heterocycl. Chem. 1997, 34, 1597 and references cited therein
15. Sata, N. U.; Sugano, M.; Matsunaga, S.; Fusetani, N. Tetrahedron Lett. 1999, 40, 719-722
16. Nam, N.-H.; Kim, Y.; You, Y.-J.; Hong, D.-H.; Kim, H.-M.; Ahn, B.-Z. Bioorg. Med. Chem. Lett. 2001, 11, 3073-3076
17. Kudo, N.; Taniguchi, M.; Furuta, S.; Sato, K.; Endo, T.; Honma, T. J. Agric. Food Chem. 1998, 46, 5305-5312
18. Hanada, M.; Sugawara, K.; Koko, K.; Toda, S.; Nishiyama, Y.; Tomita, K.; Yamamoto, H.; Konishi, M.; Oki, T. J. Antibiot. 1992, 45, 1746
19. For synthesis of dihalovinylamine, see: Couty, S.; Barbazanges, M.; Meyer, C.; Cossy, J. Synlett 2005, 6, 905
20. Brückner, D. Tetetrahedron 2006, 62, 3809
21. The gem -dibromination of formamides only works when an N -carbonyl protecting group on the formamide is present. Thus, β,β- dibromoenamides having a Boc or Piv group can be prepared. However, attempts to react other carbonyl protecting groups such as methylformyl (-COOMe) or benzoyl groups failed.
22. Biscoe, M. R.; Fors, B. P.; Buchwald, S. L. J. Am. Chem. Soc. 2008, 130, 6686
23. Momiyama, N.; Kanan, M. W.; Liu, D. R. J. Am. Chem. Soc. 2007, 129, 2230
24. 2O did not undergo H/D exchange under the reaction conditions.
25. Shi, J.; Zeng, X.; Negishi, E. Org. Lett. 2003, 5, 1825
26. Negishi, E.; Shi, J.; Zeng, X. Tetrahedron 2005, 61, 9886
27. 31P NMR) were initially observed in 1:1 ratio at 60 °C, the signal at 46.8 ppm slowly disappeared. We believe that these two signals correspond to trans-and cis -vinylpalladium 10 and 14. See the Supporting Information for details.
28. For hydrolysis of cyclic amide hemiacetals, see: Marinelli, E. R.; Johnson, F.; Iden, C. R.; Yu, P. L. I. Chem. Res. Toxicol. 1990, 3, 49
29. Vorbruggen, H.; Krolikiewicz, K. Tetrahedron 1993, 49, 9