A facile access to N-sulfonylimidates and their synthetic utility for the transformation to amidines and amides

Organic Letters

Volumn 8, Issue 7, 2006, Pages 1347-1350

  Yoo, Eun Jeong ^a   Bae, Imhyuck ^a   Cho, Seung Hwan ^a   Han, Hoon ^a   Chang, Sukbok ^a  

^a Korea Advanced Institute of Science and Technology (KAIST)   (South Korea)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33645942102     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol060056j     Document Type: Article

References (37)

1. (a) Kolb, H. C.; Finn, M. G.; Sharpless, K. B. Angew. Chem., Int. Ed. 2001, 40, 2004-2021.
2. (b) Trost, B. M. Science 1991, 254, 1471-1477.
3. (c) Trost, B. M. Angew. Chem., Int. Ed. Engl. 1995, 34, 259-281.
4. (d) Sheldon, R. A. Pure Appl. Chem. 2000, 72, 1233-1246.
5. (e) Wangelin, A. J.; Neumann, H.; Cordes, D.; Klaus, S.; Strubing, D.; Beller, M. Chem. Eur. J. 2003, 9, 4286-4294.
6. (a) Tietze, L. F. Chem. Rev. 1996, 96, 115-136.
7. (b) Dömling, A.; Ugi, I. Angew. Chem., Int. Ed. 2000, 39, 3168-3210.
8. (a) Bae, I.; Han, H.; Chang, S. J. Am. Soc. Chem. 2005, 127, 2038-2039.
9. (b) Cho, S. H.; Yoo, E. J.; Bae, I.; Chang, S. J. Am. Chem. Soc. 2005, 127, 16046-16047.
10. (a) Neilson, D. G. In The Chemistry of Amdines and Imidates; Patai, S., Ed.; John Wiley & Sons: London, UK, 1975; Chapter 8.
11. (b) Kantlehner, W. Synthesis of Iminium Salts, Orthoesters and Related Compounds. In Comprehensive Organic Synthesis; Trost, B. M., Fleming, I., Eds.; Pergamon; Oxford, UK, 1991; Vol. 2, pp 485-599.
12. (c) Baindur, N.; Neumeyer, J. L.; Niznik, H. B.; Bozowej, N. H.; Jarvie, K. R.; Seeman, P.; Garlick, R. K.; Miller, J. J., Jr. J. Med. Chem. 1988, 31, 2069-2071.
13. (a) Pinner, A.; Klein, F. Chem. Ber. 1877, 10, 1889-1897.
14. (b) Gavin, D. J.; Mojica, C. A. Org. Process Res. Dev. 2001, 5, 659-664.
15. (c) For a review, see: Roger, R.; Neilson, D. G. Chem. Rev. 1961, 61, 179-211.
16. (a) Saluste, C. G.; Whitby, R. J.; Furber, M. Tetrahedron Lett. 2001, 42, 619-6194.
17. (b) Nakajima, N.; Saito, M.; Kudo, M.; Ubukata, M. Tetrahedron 2002, 58, 3579-3588.
18. (c) Kishore, K.; Tetala, R.; Whitby, R. J.; Light, M. E.; Hurtshouse, M. B. Tetrahedron Lett. 2004, 45, 6991-6994.
19. (d) Yadav, V. K.; Babu, K. G. Eur. J. Org. Chem. 2005, 452-456.
20. For seminal reports on the Cu-catalyzed cycloaddition between 1-alkynes and alkyl(aryl) azides. see: (a) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless, K. B. Angew. Chem., Int. Ed. 2002, 41, 2596-2599.
21. (b) Tornoe, C. W.; Christensen, C.; Meldal, M. J. Org. Chem. 2002, 67, 3057-3064.
22. See the Supporting Information tor details.
23. Sauers, R. R.; Van Arnum, S. D. Phosphorus, Sulfur, Silicon, Relat. Elem. 2003, 178, 2169-2181.
24. (a) Himo, F.; Lovell, T.; Hilgraf, R.; Rostovtsev, V. V.; Noodleman, L.; Sharpless, K. B.; Fokin, V. V. J. Am. Chem. Soc. 2005, 127, 210-216.
25. (b) Rodionov, V. O.; Fokin, V. V.; Finn, M. G. Angew. Chem., Int. Ed. 2005, 44, 2210-2215.
26. We thank one referee for this suggestion. A similar transformation of 5-lithiated triazoles into the corresponding ynamides has been reported: (a) Raap, R. Can. J. Chem. 1971, 49, 1792-1798.
27. (b) Gilchrist, T. L. Adv. Heteroycl. Chem. 1987, 41, 41-74.
28. 3N was used as a base, the formation of triuzole species was not observed. The difference in the acidity of conjugated ammonium ions between triethylamine and 2,6-lutidine may be attributed to these outcomes. The more acidic 2.6-lutidinium ion [pKa(THF): 7.2] relative to triethylammonium salt [pKa(THF): 12.5], formed presumably during the course of generation of copper acetylides. is believed to transfer its proton more readily to the postulated copper triazole species (B in Scheme 1) leading to the triazole species 5. For a reference on the indicated acidity values, see: Rodima, T.; Kaljurand, I.; Pihl, A.; Maemets, V.; Leito, I.; Koppel. I. J. Og. Chem. 2002, 67, 1873-1881.
29. Kochi, T.; Ellman, J. A. J. Am. Chem. Soc. 2004, 126, 15652-15653.
30. For example, a reaction of phenylacetylene, p-toluenesulfonyl azide, and morpholine provided the corresponding amidine 6c in a poor 19% yield under the previously described conditions (ref 3a).
31. For the rearrangement of allylic acyl(aryl)imidates, see: (a) Overman, L. E. J. Am. Chem. Soc. 1978, 98, 2901-2910.
32. (b) Overman, L. E. Acc. Chem. Res. 1980, 13, 218-224.
33. (c) Hollis, T. K.; Overman, L. E. J. Organomer. Chem. 1999, 576, 290-299. For a recent report on the rearrangement of allylic phosphorimidates, see:
34. (d) Chen, B.; Mapp, A. K. J. Am. Chem. Soc. 2004, 126, 5364-5365.
35. For selected examples, see: (a) Danishefsky, S.; Lee, J. Y. J. Am. Chem. Soc. 1989, 111, 4829-4837.
36. (b) Nishikawa, T.; Asai, M.; Ohyabu, N.; Yamamoto, N.; Fukuda, Y.; Isobe, M. Tetrahedron 2001, 57, 3875-3883.
37. (c) Kim, S.; Lee, T.; Lee, E.; Lee, J.; Fan, G.-J.; Lee, S. K.; Kim, D. J. Org. Chem. 2004, 67, 3144-3149.