Enantioselective organocatalytic singly occupied molecular orbital activation: The enantioselective α-enolation of aldehydes

Journal of the American Chemical Society

Volumn 129, Issue 22, 2007, Pages 7004-7005

  Jang, Hye Young ^a   Hong, Jun Bae ^b   MacMillan, David W C ^b  

^a Ajou University   (South Korea)

^b NONE

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE DERIVATIVE;

ARTICLE; CATALYSIS; CHEMICAL STRUCTURE; CYCLIZATION; ENANTIOSELECTIVITY; HYDROLYSIS;

ALDEHYDES; ALLYL COMPOUNDS; CATALYSIS; CYCLIZATION; KETONES; MODELS, MOLECULAR; SILANES; STEREOISOMERISM;

EID: 34250205588     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja0719428     Document Type: Article

References (16)

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3. The Organometallic Chemistry of the Transition Metals, 4th ed.; Crabtree, R. H.; Wiley-Interscience: Hoboken, NJ, 2005.
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7. Beeson, T. D.; Mastracchio, A.; Hong, J. B.; Ashton, K.; MacMillan, D. W. C. Science 2007, 316, 582.
8. The studies outlined in this manuscript were first described in a NIH submission to SBCA October 1st, 2005 and reported widely by D.W.C.M. in public presentations including the following: March 31st, Amgen, Thousand Oaks, CA; April 27th, 2006, Manchester U.K.; June 13th, 2006, IUPAC, Merida, Mexico; July 25th, 2006 IUPAC Kyoto, Japan; Sept 11th, 2006, ACS, San Francisco, CA.
9. For prior work related to the chemistry of oxidized enamines, see: (a) Chiba, T.; Okimoto, H.: Hamaguchi, H.; Imanishi, T.; Yoshida, K. J. Org. Chem. 1979, 44, 3519.
10. (b) Cossy, J.; Bouzide, A.; Leblanc, C. Synlett 1993, 202.
11. (c) Cossy, J.; Bouzide, A. J. Chem. Soc., Chem. Commun. 1993, 1218.
12. Shortly before submission of this manuscript, studies on the α-oxidation of radical cations with moderate enantioselectivity were reported, see: Sibi, M.; Hasegawa, M. J. Am. Chem. Soc. 2007, 129, 4124.
13. Narasaksa, K.; Okauchi, T.; Tanaka, K.; Murakami, M. Chem. Lett. 1992, 2099.
14. DFT calculations performed using B3LYP/6-311+G(2d,p)//B3LYP/6-31G(d).
15. 2O resulted in useful levels of enantio-selectivity (≥90% ee) but diminished yields (25-68% yield). Products arising from enamine-aldehyde aldol were not observed in this study.
16. The use of TMS enolethers in Table 2, entries 7 and 8, provides the corresponding products in 39% yield, 73% ee and ≤10% yield, 0% ee.