• Title/Summary/Keyword: Enones

Search Result 34, Processing Time 0.022 seconds

Facile One-Pot Synthesis of 1,3,5-Trisubstituted Pyrazoles from α,β-Enones

  • Yu, Jin;Kim, Ko Hoon;Moon, Hye Ran;Kim, Jae Nyoung
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.6
    • /
    • pp.1692-1696
    • /
    • 2014
  • A practical and efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from ${\alpha},{\beta}$-enones and arylhydrazine hydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the corresponding pyrazolines and an acid-catalyzed aerobic oxidation process.

Organocatalytic Enantioselective Michael Addition of α-Nitroacetate to α,β-Unsaturated Enones: A Route to Chiral γ-Nitro Ketones and δ-Keto Esters

  • Moon, Hyoung-Wook;Kim, Dae-Young
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.1
    • /
    • pp.291-295
    • /
    • 2011
  • The catalytic enantioselective conjugate addition reaction of $\alpha$-nitroacetate to $\alpha,\beta$-unsaturated enones promoted by chiral bifunctional organocatalysts is described. The treatment of $\alpha$-nitroacetate to $\alpha,\beta$-unsaturated enones afforded the corresponding Michael adducts with high enantioselectivity. The conjugate addition adducts are easily converted to chiral $\gamma$-nitro ketones and $\delta$-keto esters.

Photo-enhanced Reduction of Conjugated Enones with NaBH$_4$

  • Shim, Sang-Chul;Yeo, Ho-Seop
    • Bulletin of the Korean Chemical Society
    • /
    • v.8 no.3
    • /
    • pp.202-205
    • /
    • 1987
  • The reduction of some cyclic conjugated enones with electron-donating substituent on C-3 by sodium borohydride was accelerated on irradiation. The photo-enhanced reduction seems to undergo through zwitterionic species formed from the (n, ${\pi}^{\ast}$) triplet state of conjugated enones, followed by hydride attack to yield unsaturated or saturated alcohols.

Regioselective Synthesis of 1,3,4,5-Tetrasubstituted Pyrazoles from α-Alkenyl-α,β-Enones Derived from Morita-Baylis-Hillman Adducts

  • Kim, Sung Hwan;Lim, Jin Woo;Yu, Jin;Kim, Jae Nyoung
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.10
    • /
    • pp.2915-2920
    • /
    • 2013
  • Convenient synthetic method for 4-arylethylpyrazoles and 4-styrylpyrazoles was developed using ${\alpha}$-alkenyl-${\alpha},{\beta}$-enones readily accessed from the Morita-Baylis-Hillman reaction. For the synthesis of 4-arylethylpyrazole, the reactions with arylhydrazines needed to be carried out in o-dichlorobenzene under $N_2$ balloon atmosphere. On the other hand, 4-styrylpyrazoles required the reactions in ethanol under $O_2$ balloon atmosphere.