Catalytic generation of activated carboxylates from enals: A product-determining role for the base

Organic Letters

Volumn 7, Issue 18, 2005, Pages 3873-3876

  Sohn, Stephanie S ^a   Bode, Jeffrey W ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 24944439544     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol051269w     Document Type: Article

References (25)

1. (a) For catalytic methods for the esterifications of carboxylic acids, see: Otera, J. Esterification: Methods, Reactions, and Applications; Wiley & Sons: New York, 2003.
2. (b) Ishihara, K. Nakagawa, S.; Sakakura, A. J. Am. Chem. Soc. 2005, 127, 4168-4169.
3. For NHC-catalyzed transesterifications, see: (a) Grasa, G. A.; Sing, E.; Nolan, S. P. Synthesis 2004, 971-985.
4. (b) Nyce, G. W.; Glauser, T.; Conor, E. F.; Möck, A.; Waymouth, R. M.; Hedrick, J. L. J. Am. Chem. Soc. 2003, 125, 3046-3056.
5. (c) Movassaghi, M.; Schmidt, M. A. Org. Lett. 2005, 7, 2453-2456.
6. Chow, K. Y.-K.; Bode, J. W. J. Am. Chem. Soc. 2004, 126, 8126-8127.
7. For the catalytic generation of activated carboxylates from α-chloroaldehydes, see: Reynolds, N. T.; Read de Alaniz, J.; Rovis, T. J. Am. Chem. Soc. 2004, 126, 9518-9519.
8. For a metal-mediated redox esterification of cinnamaldehyde, see: de Vries, J. G.; Roelfes, G.; Green, R. Tetrahedron Lett. 1998, 39, 8329-8332.
9. (a) Sohn, S. S.; Rosen, E. L.; Bode, J. W. J. Am. Chem. Soc. 2004, 126, 14370-14371.
10. (b) He, M.; Bode, J. W. Org. Lett. 2005, 7, 3131-3134.
11. Glorius has independently reported a related method: Burstein, C.; Glorius, F. Angew. Chem. Int. Ed. 2004, 43, 6205-6208.
12. Chan, A.; Scheidt, K. A. Org. Lett. 2005, 7, 905-908.
13. For the organocatalytic, asymmetric conjugate reduction of α,β-unsaturated aldehydes to the saturated aldehydes in the presence of a hydride donor, see: (a) Ouellet, S. G.; Tuttle, J. B.; Macmillan, D. W. C. J. Am. Chem. Soc. 2005, 127, 32-33.
14. (b) Yang, J. W.; Hechavarria Fonseca, M. T.; List, B. L. Angew. Chem., Int. Ed. 2004, 43, 6660-6662.
15. (c) Yang, J. W.; Hechavarria Fonseca, M. T.; Vignola, N.; List, B. L. Angew. Chem., Int. Ed. 2005, 44, 108-110.
16. (a) Synthesis of related azolium catalysts has been described: Knight, R. L.; Leeper, F. J. J. Chem. Soc., Perkins Trans. 1 1998, 1891-1893.
17. (b) Kerr, M. S.; Read de Alaniz, J.; Rovis, T. J. Org. Chem. 2005, 70, 5725-5728. We are grateful to Prof. Rovis for a preprint of this work.
18. We postulate that the allylic strain inherent to the key homoenolate equivalent inhibits protonation at the β-position by impeding the formation of a fully conjugated system.
19. We have shown, by deuterium labeling experiments, that the catalyst reacts with a-methylcinnamaldehyde to give A (or its geometric isomer). This process, however, is unproductive and does not promote the formation of any products other than the deuterated aldehyde.
20. 3OD show rapid exchange of the C2 proton with deuterium.
21. (a) Rodima, T.; Kaljurand, I.; Pihl, A.; Mäemets, V.; Leito, I.; Koppel, I. A. J. Org. Chem. 2002, 67, 1873-1881.
22. (b) Bordwell, F. G. Acc. Chem. Res. 1988, 21, 456-463.
23. The apparently related conversion of β-formyl acrylic acid to succinic acid by aqueous cyanide ion has been described: (a) Nowak, R. M. J. Org. Chem. 1963, 28, 1182-1187.
24. (b) Franzen, V.; Fikentscher, L. Liebigs Ann. 1959, 623, 68-73.
25. For a similar overall transformation via the stoichiometric intermediacy of TMS cyanohydrins, see: Kawabata, H.; Hayashi, M. Tetrahedron Lett. 2002, 43, 5645-5647.