메뉴 건너뛰기




Volumn 20, Issue 41, 2014, Pages 13217-13225

Solvent-Controlled Bifurcated Cascade Process for the Selective Preparation of Dihydrocarbazoles or Dihydropyridoindoles

Author keywords

Cascade reaction; dihydrocarbazole; dihydropyridoindole; nitrone; solvent effect

Indexed keywords

POLYCYCLIC AROMATIC HYDROCARBONS; SOLVENTS; SYNTHESIS (CHEMICAL);

EID: 84941049203     PISSN: 09476539     EISSN: 15213765     Source Type: Journal    
DOI: 10.1002/chem.201403268     Document Type: Article
Times cited : (51)

References (87)
  • 11
    • 84879880639 scopus 로고    scopus 로고
    • For a review of diversity-oriented natural product synthesis that includes examples of reagent-, substrate-, and catalyst-controlled cascade reactions, see.
    • For a review of diversity-oriented natural product synthesis that includes examples of reagent-, substrate-, and catalyst-controlled cascade reactions, see:, C. Serba, N. Winssinger, Eur. J. Org. Chem. 2013, 4195.
    • (2013) Eur. J. Org. Chem. , pp. 4195
    • Serba, C.1    Winssinger, N.2
  • 32
    • 84957925806 scopus 로고    scopus 로고
    • For examples of biologically active, partially saturated carbazoles and pyrido[1,2-a]indoles, see
    • For examples of biologically active, partially saturated carbazoles and pyrido[1,2-a]indoles, see:
  • 45
    • 1542499040 scopus 로고    scopus 로고
    • in (Ed.: G. A. Cordell), Academic Press, New York
    • J. Bosch, J. Bonjoch, M. Amat, in The Alkaloids (Ed.:, G. A. Cordell,), Academic Press, New York, 1996, Vol. 48, pp. 75-189;
    • (1996) The Alkaloids , vol.48 , pp. 75-189
    • Bosch, J.1    Bonjoch, J.2    Amat, M.3
  • 58
    • 84957925807 scopus 로고    scopus 로고
    • 2 was excluded from the reaction of 3 n with 4 a to minimize competing hydrolysis of the aldehyde-derived nitrone.
    • 2 was excluded from the reaction of 3 n with 4 a to minimize competing hydrolysis of the aldehyde-derived nitrone.
  • 59
    • 84867703800 scopus 로고    scopus 로고
    • See Supporting Information for copper-mediated nitrone synthesis. See the following for related examples of CN bond coupling to form nitrones:, and ref. [5].
    • See Supporting Information for copper-mediated nitrone synthesis. See the following for related examples of CN bond coupling to form nitrones:, D.-L. Mo, D. J. Wink, L. L. Anderson, Org. Lett. 2012, 14, 5180 and ref. [5].
    • (2012) Org. Lett. , vol.14 , pp. 5180
    • Mo, D.-L.1    Wink, D.J.2    Anderson, L.L.3
  • 71
    • 84957925808 scopus 로고    scopus 로고
    • 4 to prevent hydrolysis of the aldehyde-derived nitrones.
    • 4 to prevent hydrolysis of the aldehyde-derived nitrones.
  • 82
    • 84957925809 scopus 로고    scopus 로고
    • Less than 5 % 1 a - 1 n were separated during purification of 2 a - 2 n indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
    • Less than 5 % 1 a-1 n were separated during purification of 2 a-2 n indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
  • 83
    • 84957925810 scopus 로고    scopus 로고
    • Less than 5 % 1 o - 1 x, 1 bb were separated during purification of 2 o - 2 x, 2 bb indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
    • Less than 5 % 1 o-1 x, 1 bb were separated during purification of 2 o-2 x, 2 bb indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
  • 84
    • 84957925811 scopus 로고    scopus 로고
    • Less than 5 % 6 - 8 were separated during purification of 25 - 27 and less than 5 % of the corresponding dihydrocarbazoles were separated from 28 - 32 indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
    • Less than 5 % 6-8 were separated during purification of 25-27 and less than 5 % of the corresponding dihydrocarbazoles were separated from 28-32 indicating that the 2: 1 ratios for all of these reactions were greater than or equal to 10:1.
  • 85
    • 84957925812 scopus 로고    scopus 로고
    • Irrespective of the reaction media, amide substitution on the allene strongly favors the formation of dihydropyridoindoles, and mixtures of 1 and 2 were even observed when these reagents were subjected to toluene-mediated reaction conditions previously optimized for dihydrocarbazole synthesis.
    • Irrespective of the reaction media, amide substitution on the allene strongly favors the formation of dihydropyridoindoles, and mixtures of 1 and 2 were even observed when these reagents were subjected to toluene-mediated reaction conditions previously optimized for dihydrocarbazole synthesis.
  • 87
    • 84957925813 scopus 로고    scopus 로고
    • 1H NMR spectrum. Dihydrocarbazoles 1 that have been prepared from ketone-derived nitrones are stable in air at 25 °C and only begin to oxidize slowly to the corresponding carbazoles at higher temperatures (5-10 % after 18 h at 80 °C). Dihydrocarbazoles 1 that have been prepared from aldehyde-derived nitrones are stable at -40 °C but slowly oxidize at 25 °C in air and more quickly at higher temperatures (∼50 % after 18 h at 80 °C). Dihydropyridoindoles 2 show no sign of oxidation when heated in air for 18 h at 80 °C.
    • 1H NMR spectrum. Dihydrocarbazoles 1 that have been prepared from ketone-derived nitrones are stable in air at 25 °C and only begin to oxidize slowly to the corresponding carbazoles at higher temperatures (5-10 % after 18 h at 80 °C). Dihydrocarbazoles 1 that have been prepared from aldehyde-derived nitrones are stable at -40 °C but slowly oxidize at 25 °C in air and more quickly at higher temperatures (∼50 % after 18 h at 80 °C). Dihydropyridoindoles 2 show no sign of oxidation when heated in air for 18 h at 80 °C.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.