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Volumn 63, Issue 26, 2007, Pages 5820-5831

Toward a rational design of the assembly structure of polymetallic asymmetric catalysts: design, synthesis, and evaluation of new chiral ligands for catalytic asymmetric cyanation reactions

Author keywords

[No Author keywords available]

Indexed keywords

AZIRIDINE DERIVATIVE; GADOLINIUM; LIGAND; MESO AZIRIDINE DERIVATIVE; METAL; UNCLASSIFIED DRUG;

EID: 34248684099     PISSN: 00404020     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tet.2007.02.081     Document Type: Article
Times cited : (75)

References (49)
  • 5
    • 34248653921 scopus 로고    scopus 로고
    • For reviews, see:
  • 10
    • 34248674784 scopus 로고    scopus 로고
    • Asymmetric synthesis of γ-amino acids mainly relied on diastereoselective reactions before Jacbosen's contribution (Ref. 8). For selected recent examples, see:
  • 18
    • 21544444468 scopus 로고    scopus 로고
    • For a review about the utility of chiral ligands 1 and 2, see:
    • For a review about the utility of chiral ligands 1 and 2, see:. Kanai M., Kato N., Ichikawa E., and Shibasaki M. Synlett (2005) 1491
    • (2005) Synlett , pp. 1491
    • Kanai, M.1    Kato, N.2    Ichikawa, E.3    Shibasaki, M.4
  • 19
    • 34248641287 scopus 로고    scopus 로고
    • note
    • Addition of TFA slightly, but constantly, improved the enantioselectivity. ESIMS studies demonstrated that TFA is incorporated in the polymetallic complex. TFA likely bridges two Gd metals in the complex, and thus finely tunes the relative position of the two metals. In addition, TFA enhances the Lewis acidity of Gd in the catalyst.
  • 22
    • 34248673877 scopus 로고    scopus 로고
    • Silverman, R. B.; Andruszkiewicz, R.; Yuen, P. W.; Sobieray, D. M.; Franklin, L. C.; Schwindt, M. A. U.S. Patent 5,563,175, 1996;
  • 23
    • 0042932780 scopus 로고    scopus 로고
    • For recent catalytic enantioselective synthesis of pregabalin, see:
    • For recent catalytic enantioselective synthesis of pregabalin, see:. Hoge G. J. Am. Chem. Soc. 125 (2003) 10219
    • (2003) J. Am. Chem. Soc. , vol.125 , pp. 10219
    • Hoge, G.1
  • 31
    • 34248658678 scopus 로고    scopus 로고
    • note
    • An extreme example in which the 2:3 complex and the 4:5+μ-oxo crystal demonstrated contrasting catalyst function was the asymmetric Strecker reaction of ketoimines. These two asymmetric catalysts produced reversed enantioselectivity in an excellent level. See Ref. 14.
  • 32
    • 34248657166 scopus 로고    scopus 로고
    • note
    • Crystal structure of another polymetallic complex (La-1=6:8+2OH complex) described in Ref. 14 also contained this general module.
  • 35
    • 34248637194 scopus 로고    scopus 로고
    • note
    • N2′-type reaction.
  • 38
    • 34248676170 scopus 로고    scopus 로고
    • note
    • Similar temperature dependency was also observed when using 18f and 18g as substrates.
  • 39
    • 34248664220 scopus 로고    scopus 로고
    • note
    • The syn isomer should be generated from the kinetically produced anti isomer through catalyst-mediated epimerization of the benzylnitrile moiety.
  • 40
    • 34248660116 scopus 로고    scopus 로고
    • note
    • In the reaction of 18f, which has a relatively small size compared to 18g and 18i, the liberation of the product might be hindered due to the high coordinating ability of the product to the metal.
  • 41
    • 1642264109 scopus 로고    scopus 로고
    • The protic additive activated the Gd-1=2:3 catalyst by forming a proton-containing complex, see:
    • The protic additive activated the Gd-1=2:3 catalyst by forming a proton-containing complex, see:. Kato N., Suzuki M., Kanai M., and Shibasaki M. Tetrahedron Lett. 45 (2004) 3147
    • (2004) Tetrahedron Lett. , vol.45 , pp. 3147
    • Kato, N.1    Suzuki, M.2    Kanai, M.3    Shibasaki, M.4
  • 43
    • 34248681722 scopus 로고    scopus 로고
    • note
    • Crystallographic data for the structural analysis have been deposited with the Cambridge Crystallographic Data Centre, CCDC No. 637203 for the Gd-4=3:4+2OH complex (Fig. 3b) and CCDC No. 637202 for 17 (Fig. 4).


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.