메뉴 건너뛰기




Volumn 73, Issue 19, 2008, Pages 7837-7840

A novel synthesis of 1-nosyl 3,3-dichloro-β-lactams and derivatives

Author keywords

[No Author keywords available]

Indexed keywords

CHEMICAL REACTIONS; NITROGEN COMPOUNDS;

EID: 53049099808     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo8014193     Document Type: Article
Times cited : (16)

References (61)
  • 17
    • 0035215545 scopus 로고    scopus 로고
    • For leading references on the chemistry of β-lactams, see: a
    • For leading references on the chemistry of β-lactams, see: (a) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Oiarbide, M. Synlett 2001, 1813.
    • (2001) Synlett , pp. 1813
    • Palomo, C.1    Aizpurua, J.M.2    Ganboa, I.3    Oiarbide, M.4
  • 21
    • 0004030277 scopus 로고
    • For leading references on the biological activity of β-lactams, see: a, Morin, R. B, Gorman, M, Eds, Academic Press: New York, Vols
    • For leading references on the biological activity of β-lactams, see: (a) Chemistry and Biology of β-Lactam Antibiotics; Morin, R. B.; Gorman, M., Eds.; Academic Press: New York, 1982; Vols. 1-3.
    • (1982) Chemistry and Biology of β-Lactam Antibiotics , vol.1-3
  • 25
    • 0037176279 scopus 로고    scopus 로고
    • Recent uses of dichloroketene: (a) Brocksom, T. J.; Coelho, F.; Depres, J.-P.; Greene, A. E.; Freire de Lima, M. E.; Hamelin, O.; Hartmann, B.; Kanazawa, A. M.; Wang, Y. J. Am. Chem. Soc. 2002, 124, 15313.
    • Recent uses of dichloroketene: (a) Brocksom, T. J.; Coelho, F.; Depres, J.-P.; Greene, A. E.; Freire de Lima, M. E.; Hamelin, O.; Hartmann, B.; Kanazawa, A. M.; Wang, Y. J. Am. Chem. Soc. 2002, 124, 15313.
  • 40
    • 53049083800 scopus 로고    scopus 로고
    • The dehalogenation reaction of trichloroacetyl chloride in the presence of the Zn-Cu amalgam did not afford satisfactory results due to the decomposition of starting imines 1-3
    • The dehalogenation reaction of trichloroacetyl chloride in the presence of the Zn-Cu amalgam did not afford satisfactory results due to the decomposition of starting imines 1-3.
  • 41
    • 37349022185 scopus 로고    scopus 로고
    • N-Nosyl imines were also used in the Staudinger reaction with arylalkylketenes: Sereda, O.; Wilhelm, R. Synlett 2007, 19, 3032.
    • N-Nosyl imines were also used in the Staudinger reaction with arylalkylketenes: Sereda, O.; Wilhelm, R. Synlett 2007, 19, 3032.
  • 42
    • 53049087923 scopus 로고    scopus 로고
    • The best conditions were obtained using 2 equiv of base and slowly adding acetyl chloride (2 equiv) for 2 h, in order to avoid the decomposition and polymerization of dichloroketene
    • The best conditions were obtained using 2 equiv of base and slowly adding acetyl chloride (2 equiv) for 2 h, in order to avoid the decomposition and polymerization of dichloroketene.
  • 43
    • 0034624432 scopus 로고    scopus 로고
    • 4Si at high temperature (73-89% yield): (a) Hayashi, T.; Ishigedani, M. J. Am. Chem. Soc. 2000, 122, 976.
    • 4Si at high temperature (73-89% yield): (a) Hayashi, T.; Ishigedani, M. J. Am. Chem. Soc. 2000, 122, 976.
  • 45
    • 53049101090 scopus 로고    scopus 로고
    • The purification on both silica gel and aluminum oxide was not effective due to the decomposition of most products. Simple crystallization was more efficient
    • The purification on both silica gel and aluminum oxide was not effective due to the decomposition of most products. Simple crystallization was more efficient.
  • 46
    • 0034693178 scopus 로고    scopus 로고
    • This base should not attack the ketene because of its steric hindrance: Tennyson, R, Romo, D. J. Org. Chem. 2000, 65, 7248
    • This base should not attack the ketene because of its steric hindrance: Tennyson, R.; Romo, D. J. Org. Chem. 2000, 65, 7248.
  • 47
    • 53049101790 scopus 로고    scopus 로고
    • 2-t-Bu), and catalysts (from 0.1 to 0.3 equiv) and addition modes of acyl chloride were tested. Nevertheless, no improvement in the enantiomeric excess was observed, leading to poorer results than the 20% ee achieved with TMS-quinidine. It is important to note that, in all assays, the reaction provided the β-lactam 4a in high conversion (>85%).
    • 2-t-Bu), and catalysts (from 0.1 to 0.3 equiv) and addition modes of acyl chloride were tested. Nevertheless, no improvement in the enantiomeric excess was observed, leading to poorer results than the 20% ee achieved with TMS-quinidine. It is important to note that, in all assays, the reaction provided the β-lactam 4a in high conversion (>85%).
  • 56
    • 53049096453 scopus 로고    scopus 로고
    • The deprotection of the N-nosyl group of 8 was never observed even when an excess of thiolate was used.
    • The deprotection of the N-nosyl group of 8 was never observed even when an excess of thiolate was used.
  • 57
    • 53049088780 scopus 로고    scopus 로고
    • 2NEt, but no variation was observed after the addition of the bases in comparison with the starting imine.
    • 2NEt, but no variation was observed after the addition of the bases in comparison with the starting imine.
  • 58
    • 53049089530 scopus 로고    scopus 로고
    • We were not able to detect any intermediate by in situ IR (see Supporting Information). On the other hand, a direct and fast transformation to β-lactam 4g was observed.
    • We were not able to detect any intermediate by in situ IR (see Supporting Information). On the other hand, a direct and fast transformation to β-lactam 4g was observed.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.