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Volumn 70, Issue 13, 2005, Pages 5235-5248

Lewis base catalyzed, enantioselective aldol addition of methyl trichlorosilyl ketene acetal to ketones

Author keywords

[No Author keywords available]

Indexed keywords

ADDITION REACTIONS; CATALYSIS; CHLORINE COMPOUNDS; COMPLEXATION; COMPUTATIONAL METHODS; SILICON COMPOUNDS; STEREOCHEMISTRY; SUBSTITUTION REACTIONS;

EID: 20844454091     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo0506276     Document Type: Article
Times cited : (125)

References (81)
  • 7
    • 0000699983 scopus 로고    scopus 로고
    • Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer-Verlag: Heidelberg, Chapter 29.1
    • (b) Carreira, E. M. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer-Verlag: Heidelberg, 1999; Vol. III, Chapter 29.1.
    • (1999) Comprehensive Asymmetric Catalysis , vol.3
    • Carreira, E.M.1
  • 8
    • 20844456501 scopus 로고    scopus 로고
    • Otera, J., Ed.; Wiley-VCH: Weinheim, Chapter 8
    • (c) Carreira, E. M. In Modern Carbonyl Chemistry; Otera, J., Ed.; Wiley-VCH: Weinheim, 2000; Chapter 8.
    • (2000) Modern Carbonyl Chemistry
    • Carreira, E.M.1
  • 10
    • 11844259698 scopus 로고    scopus 로고
    • Mahrwald, R., Ed.; Wiley-VCH: Weinheim
    • (e) Modern Aldol Reactions; Mahrwald, R., Ed.; Wiley-VCH: Weinheim, 2004.
    • (2004) Modern Aldol Reactions
  • 13
    • 0032554099 scopus 로고    scopus 로고
    • For catalytic enantioselective organometallic additions to ketones, see: (a) Dosa, P. I.; Fu, G. C. J. Am. Chem. Soc. 1998, 120, 445-446.
    • (1998) J. Am. Chem. Soc. , vol.120 , pp. 445-446
    • Dosa, P.I.1    Fu, G.C.2
  • 27
    • 0037620632 scopus 로고    scopus 로고
    • Shibasaki has recently described a catalytic aldol addition of trialkylsilyl ketene acetals to ketones. One example of an enantioselective addition to 3-pentanone was reported. Oisaki, K.; Suto, Y.; Kanai, M.; Shibasaki, M. J. Am. Chem. Soc. 2003, 125, 5644-5.
    • (2003) J. Am. Chem. Soc. , vol.125 , pp. 5644-5645
    • Oisaki, K.1    Suto, Y.2    Kanai, M.3    Shibasaki, M.4
  • 45
    • 0037165679 scopus 로고    scopus 로고
    • A preliminary account of this work has already appeared. Denmark, S. E.; Fan, Y. J. Am. Chem. Soc. 2002, 124, 4233-4235.
    • (2002) J. Am. Chem. Soc. , vol.124 , pp. 4233-4235
    • Denmark, S.E.1    Fan, Y.2
  • 54
    • 20844462809 scopus 로고    scopus 로고
    • Manuscript in preparation
    • The syntheses of the various bis N-oxides employed in this work constitutes a major effort that will be described separately. Denmark, S. E.; Fan, Y. Manuscript in preparation.
    • Denmark, S.E.1    Fan, Y.2
  • 56
    • 0004099399 scopus 로고
    • Mason, J., Ed.; Plenum Press: New York, Chapter 11
    • Kennedy, J. D.; McFarlane, W. In Multinuclear NMR; Mason, J., Ed.; Plenum Press: New York, 1987; Chapter 11.
    • (1987) Multinuclear NMR
    • Kennedy, J.D.1    McFarlane, W.2
  • 57
    • 20844450490 scopus 로고    scopus 로고
    • note
    • 4 have been deposited with the Cambridge Crystallographic Data Centre; deposition no. CCDC 241716. These data can be obtained free of charge via www.ccdc.cam.ac.uk/ conts/retrieving.html (or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, U.K.; fax: (+44) 1223-336-033; deposit@ccdc.cam.ac.uk).
  • 67
    • 20844461052 scopus 로고    scopus 로고
    • Ph.D. Thesis; University of Illinois
    • Pham, S. M. Ph.D. Thesis; University of Illinois, Urbana-Champaign, 2002.
    • (2002) Urbana-Champaign
    • Pham, S.M.1
  • 69
  • 70
    • 20844442202 scopus 로고    scopus 로고
    • Granovsky, A. A. www http://classic.chem.msu.su/gran/gamess/ index.html.
    • Granovsky, A.A.1
  • 72
    • 20844436057 scopus 로고    scopus 로고
    • note
    • In fact, this methoxy catalyst had been tested in the aldol reaction and was found to generate the S aldol product from acetophenone albeit in 77.5/22.5 er.
  • 73
    • 20844443572 scopus 로고    scopus 로고
    • note
    • The reason for the large energy difference between transition states derived from complexes vii and viii (i.e., ketone in equatorial positions 1 and 2) is the twisted conformation that the catalyst adopts around the silicon center (see Figure 3A). The 6,6′-substituents are located in the upper right and lower left quadrants of the complex. Because the ketene acetal is bound at an axial position, for aldolization to occur the ketone has to turn down out of the equatorial plane. In position 1, this is acceptable as the bottom right quadrant of the complex is unoccupied (the catalyst occupies the top right). However, in position 2 the R-group of the ketone is forced into the same quadrant of the complex as the 6,6′-subtituent, thereby increasing the energy of this orientation.
  • 79
    • 20844432122 scopus 로고    scopus 로고
    • Otera, J., Ed.; Wiley-VCH: Weinheim, Chapter 1
    • For a review of Lewis acid-carbonyl complexation see: Ooi, T.; Maruoka, K. In Modem Carbonyl Reactions; Otera, J., Ed.; Wiley-VCH: Weinheim, 2000, Chapter 1.
    • (2000) Modem Carbonyl Reactions
    • Ooi, T.1    Maruoka, K.2
  • 80
    • 20844433798 scopus 로고
    • This is of course, the basis for the elimination of reaction pathways via complex viii as discussed above. (40) The magnitude of the entropy change, in rising to the transition state, is likely to be different for each of the diastereomeric transition states. These changes in ΔS can be extremely significant as was clearly shown by Ingold in the Finkelstein substitution of organic halides (Ingold, C. K.; De La Mare, P. B. D.; Mackie, J. D. H. J. Chem. Soc. 1955, 3200-3236). The modest improvements in enantioselectivity observed in changing a methyl to an n-butyl group represent a very small change in the steric requirement of the catalyst and may be better understood in the decrease in entropy of the alkoxy side chain in the vi-Re pathway. The major interaction present in the complex vi-Re is between the ketone and the alkoxy substituent of the catalyst. At the transition state the n-butyl chain will be forced into one conformation, freezing out several rotational degrees of freedom.
    • (1955) J. Chem. Soc. , pp. 3200-3236
    • Ingold, C.K.1    De La Mare, P.B.D.2    Mackie, J.D.H.3


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