Addition of carbamoylsilanes to electrophilically substituted alkenes. Preparation of β-functionalized tertiary amides

Organic Letters

Volumn 7, Issue 5, 2005, Pages 771-774

  Cunico, Robert F ^a   Motta, Adalie Rodriguez ^a  

^a NORTHERN ILLINOIS UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKENE DERIVATIVE; AMIDE; CARBON; ESTER DERIVATIVE; SILANE DERIVATIVE; SILICON;

ADDITION REACTION; ARTICLE; CHEMICAL BOND; CHEMICAL PROCEDURES; CHEMICAL REACTION; REACTION ANALYSIS;

EID: 15044338850     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol040066p     Document Type: Article

References (27)

1. Cunico, R. F. Tetrahedron Lett. 2001, 42, 2931-2932.
2. For examples of how α-silylcarbonyl compounds have been used in this regard, see: Larson, G. L. Advances in Silicon Chemistry; JAI Press: Greenwich, 1996; Vol. 3, pp 243-249.
3. (a) Keck, G. E.; Grier, M. C. Synlett 1999, 1657-1659.
4. (b) Gill, G. B.; Pattenden, G.; Reynolds, S. J. J. Chem. Soc., Perkin Trans. 1 1994, 369-378 and references therein.
5. Ruthenium-catalyzed hydroamidations of alkenes are known, but mixtures of regioisomers are generally obtained: (c) Ko, S.; Han, H.; Chang, S. Org. Lett. 2003, 5, 2687-2690. (d) Kondo, T.; Okada, T.; Mitsudo, T. Organometallics 1999, 18, 4123-4127. (e) Tsuji, Y.; Ohsumi, T.; Kondo, T.; Watanabe, Y. J. Organomet. Chem. 1986, 309, 333-344.
6. Ruthenium-catalyzed hydroamidations of alkenes are known, but mixtures of regioisomers are generally obtained: (c) Ko, S.; Han, H.; Chang, S. Org. Lett. 2003, 5, 2687-2690. (d) Kondo, T.; Okada, T.; Mitsudo, T. Organometallics 1999, 18, 4123-4127. (e) Tsuji, Y.; Ohsumi, T.; Kondo, T.; Watanabe, Y. J. Organomet. Chem. 1986, 309, 333-344.
7. Ruthenium-catalyzed hydroamidations of alkenes are known, but mixtures of regioisomers are generally obtained: (c) Ko, S.; Han, H.; Chang, S. Org. Lett. 2003, 5, 2687-2690. (d) Kondo, T.; Okada, T.; Mitsudo, T. Organometallics 1999, 18, 4123-4127. (e) Tsuji, Y.; Ohsumi, T.; Kondo, T.; Watanabe, Y. J. Organomet. Chem. 1986, 309, 333-344.
8. Cunico, R. F.; Chen, J. Synth. Commun. 2003, 33, 1963-1968.
9. 3 (100°C, 4.5 h) led to disappearance of 1a, but no addition product was formed.
10. Cunico, R. F. Tetrahedron Lett. 2002, 43, 355-358.
11. Carried out in perdeuterobenzene at 75°C in the NMR spectrometer with toluene as internal standard.
12. Rapid exchange of the silyl group between the two oxygen atoms occurs: Colvin, E. W.; Beck, A. K.; Bastani, B.; Seebach, D.; Kai, Y.; Dunitz, J. D. Helv. Chim. Acta 1980, 63, 697-710.
13. For an excellent review of reactions proceeding by SET pathways, see: Rathore, R.; Kochi, J. K. Adv. Phys. Org. Chem. 2000, 35, 193-318.
14. A formal carbene trapping product has been isolated from the reaction of 1a and sulfur (Cunico, R. F.; Maity, B. C. Org. Lett. 2003, 5, 4947-4949); however, the observed carbene-like C-H bond insertion of a carbamoylsilane with methyl propynoate (vide supra) has so far not been seen when preformed nucleophilic carbenes were employed with this ester (dialkoxycarbene: Pole, D. L.; Sharma, P. K.; Warkentin, J. Can. J. Chem. 1996, 74, 1335-1340; aminoalkoxycarbene: Couture, P.; Terlouw, J. K.; Warkentin, J. J. Am. Chem. Soc. 1996, 118, 4214-4215).
15. A formal carbene trapping product has been isolated from the reaction of 1a and sulfur (Cunico, R. F.; Maity, B. C. Org. Lett. 2003, 5, 4947-4949); however, the observed carbene-like C-H bond insertion of a carbamoylsilane with methyl propynoate (vide supra) has so far not been seen when preformed nucleophilic carbenes were employed with this ester (dialkoxycarbene: Pole, D. L.; Sharma, P. K.; Warkentin, J. Can. J. Chem. 1996, 74, 1335-1340; aminoalkoxycarbene: Couture, P.; Terlouw, J. K.; Warkentin, J. J. Am. Chem. Soc. 1996, 118, 4214-4215).
16. A formal carbene trapping product has been isolated from the reaction of 1a and sulfur (Cunico, R. F.; Maity, B. C. Org. Lett. 2003, 5, 4947-4949); however, the observed carbene-like C-H bond insertion of a carbamoylsilane with methyl propynoate (vide supra) has so far not been seen when preformed nucleophilic carbenes were employed with this ester (dialkoxycarbene: Pole, D. L.; Sharma, P. K.; Warkentin, J. Can. J. Chem. 1996, 74, 1335-1340; aminoalkoxycarbene: Couture, P.; Terlouw, J. K.; Warkentin, J. J. Am. Chem. Soc. 1996, 118, 4214-4215).
17. Acylsilanes afford products attributable to silyloxycarbene intermediates under photolysis (Brook, A. G.; Kucera, H. W.; Pearce, R. Can. J. Chem. 1971, 49, 1618-1621) and thermolysis (Bassingdale, A. R.; Brook, A. G.; Harris, J. J. Organomet. Chem. 1975, 90, C6-C8).
18. Acylsilanes afford products attributable to silyloxycarbene intermediates under photolysis (Brook, A. G.; Kucera, H. W.; Pearce, R. Can. J. Chem. 1971, 49, 1618-1621) and thermolysis (Bassingdale, A. R.; Brook, A. G.; Harris, J. J. Organomet. Chem. 1975, 90, C6-C8).
19. Silicon-carbon bond formation may be advanced in the case of B, while carbon-carbon bond formation may precede silyl group transfer if C acts as a nucleophile. The former is seen as analogous to mechanisms descibing initial proton transfer followed by radical-radical coupling in radical anion/radical cation pairs: Moss, R. A.; Platz, M. S.; Jones, M., Jr. Reactive Intermediate Chemistry; Wiley-Interscience: New Jersey, 2204; pp 242-243.
20. Thermal generation of dialkoxycarbenes results in coupling products: (a) El-Saidi, M.; Kassam, K.; Pole, D. L.; Tadey, T.; Warkentin, J. J. Am. Chem. Soc. 1992, 114, 8751-8752. (b) Moss, R. A.; Wlostowski, M.; Shen, S.; Krogh-Jespersen, K.; Matro, A. J. Am. Chem. Soc. 1988, 110, 4443-4444. Some evidence exists for the dimer of an aminoalkoxycarbene: Couture, P.; Warkentin, J. Can. J. Chem. 1997, 75, 1264-1280.
21. Thermal generation of dialkoxycarbenes results in coupling products: (a) El-Saidi, M.; Kassam, K.; Pole, D. L.; Tadey, T.; Warkentin, J. J. Am. Chem. Soc. 1992, 114, 8751-8752. (b) Moss, R. A.; Wlostowski, M.; Shen, S.; Krogh-Jespersen, K.; Matro, A. J. Am. Chem. Soc. 1988, 110, 4443-4444. Some evidence exists for the dimer of an aminoalkoxycarbene: Couture, P.; Warkentin, J. Can. J. Chem. 1997, 75, 1264-1280.
22. Thermal generation of dialkoxycarbenes results in coupling products: (a) El-Saidi, M.; Kassam, K.; Pole, D. L.; Tadey, T.; Warkentin, J. J. Am. Chem. Soc. 1992, 114, 8751-8752. (b) Moss, R. A.; Wlostowski, M.; Shen, S.; Krogh-Jespersen, K.; Matro, A. J. Am. Chem. Soc. 1988, 110, 4443-4444. Some evidence exists for the dimer of an aminoalkoxycarbene: Couture, P.; Warkentin, J. Can. J. Chem. 1997, 75, 1264-1280.
23. Watanabe, H.; Kogure, T.; Nagai, Y. J. Organomet. Chem. 1972, 43, 285-291.
24. A geminal siloxy(alkyl)cyclopropane has been isolated from the photolysis of an acylsilane in the presence of diethyl fumarate: Brook, A. G.; Kucera, H. W.; Pearce, R. Can. J. Chem. 1971, 49, 1618-1621.
25. He(I) photoelectron spectroscopy.
26. The ground state of the analogous acylsilanes has been described as involving strong mixing between the oxygen lone pair and the silicon-carbon σ bond, thus leading to a lower ionization potential relative to all-carbon ketones: (a) Ramsey, B. G.; Brook, A.; Bassingdale, A. R.; Bock, H. J. Organomet. Chem. 1974, 74, C41-C45. (b) Yoshida, J.; Itoh, M.; Matsanuga, S.; Isoe, S. 1992, 57, 4877-4882.
27. The ground state of the analogous acylsilanes has been described as involving strong mixing between the oxygen lone pair and the silicon-carbon σ bond, thus leading to a lower ionization potential relative to all-carbon ketones: (a) Ramsey, B. G.; Brook, A.; Bassingdale, A. R.; Bock, H. J. Organomet. Chem. 1974, 74, C41-C45. (b) Yoshida, J.; Itoh, M.; Matsanuga, S.; Isoe, S. 1992, 57, 4877-4882.