• Title/Summary/Keyword: Aldol Reaction

Search Result 35, Processing Time 0.022 seconds

Synthesis, Characterization and Correlation Analysis in Styryl 6-Methoxy-2-Naphthyl Ketones (Styryl-6-Methoxy-2-Naphthyl Ketone 유도체의 합성 및 특성 분석)

  • Thirunarayanan, G.
    • Journal of the Korean Chemical Society
    • /
    • v.51 no.2
    • /
    • pp.115-124
    • /
    • 2007
  • A series of α, β-unsaturated ketones are synthesized by Crossed - Aldol condensation reaction, from ecofriendly 6-methoxy-2-naphthyl ketones and substituted benzaldehydes under solvent free conditions using silica-sulfuric acid as a catalytic reagent. The yields of ketones are more than 90% and the catalyst was reusable for further run. There is no appreciable decrease in the yield of product and the activity of catalyst. These chalcones were characterized by their physical constants and spectral data (IR, 1H-, 13C-NMR and Mass). These spectral data are subjected to correlate various Hammett substituent constants with single and multiparameter correlation equations. From the results of statistical analysis the influence of electronic effects of substituents on the spectral data of the ketones were explained.

First Concise Total Syntheses of Biologically Interesting Nicolaioidesin C, Crinatusin C1, and Crinatusin C2

  • Jung, Eun-Mi;Lee, Yong-Rok
    • Bulletin of the Korean Chemical Society
    • /
    • v.29 no.6
    • /
    • pp.1199-1204
    • /
    • 2008
  • The efficient and concise total syntheses of naturally occurring dihydrochalcone nicolaioidesin C, crinatusin C1, and crinatusin $C_2$ have been achieved from the readily available 2,6-dihydroxy-4-methoxyacetophenone and 2,4-dihydroxy-6-methoxyacetophenone. The key steps in the synthetic strategy were aldol reaction and Diels-Alder reaction.

Synthesis of Renewable Jet Fuel Precursors from C-C Bond Condensation of Furfural and Ethyl Levulinate in Water

  • Cai, Chiliu;Liu, Qiying;Tan, Jin;Wang, Tiejun;Zhang, Qi;Ma, Longlong
    • Korean Chemical Engineering Research
    • /
    • v.54 no.4
    • /
    • pp.519-526
    • /
    • 2016
  • Biomass derived jet fuel is proven as a potential alternative for the currently used fossil oriented energy. The efficient production of jet fuel precursor with special molecular structure is prerequisite in producing biomass derived jet fuel. We synthesized a new jet fuel precursor containing branched $C_{15}$ framework by aldol condensation of furfural (FA) and ethyl levulinate (EL), where the latter of two could be easily produced from lignocellulose by acid catalyzed processes. The highest yield of 56% for target jet fuel precursor could be obtained at the optimal reaction condition (molar ratio of FA/EL of 2, 323 K, 50 min) by using KOH as catalyst. The chemical structure of $C_{15}$ precursor was specified as (3E, 5E)-6-(furan-2-yl)-3-(furan-2-ylmethylene)-4-oxohex-5-enoic acid ($F_2E$). For stabilization, this yellowish solid precursor was hydrogenated at low temperature to obtain C=C bonds saturated product, and the chemical structure was proposed as 4-oxo-6-(tetrahydrofuran-2-yl)-3-(tetrahydrofuran-2-yl)-methyl hexanoic acid ($H-F_2E$). The successful synthesis of the new jet fuel precursors showed the significance that branched jet fuel could be potentially produced from biomass derived FA and EL via fewer steps.

A Study on the Synthesis of Nortropinone Derivatives

  • Jung, Dai-II;Park, Chil-Sung;Choi, Hak-Ki;Kim, Dong-Hee;Lee, Do-Hun;Jung, Il-Soo;Park, Yu-Mi;Choi, Soon-Kyu
    • Journal of Life Science
    • /
    • v.9 no.1
    • /
    • pp.81-83
    • /
    • 1999
  • 2,4-Disubstituted nortropinone derivatives anticipated anticonvulsant activity were respectively synthesized by the reaction of N-substituted nortropinones, ethanol, 5N-NaOH and benzaldehyde ({TEX}$R_{1}${/TEX}CHO)

  • PDF

Ammonium Acetate: An Efficient Reagent for the One-pot Synthesis of 5-Aryl-7,8,13,14-tetrahydrodibenzo[a,i] phenanthridines, 2,4-Diaryl-6,7-benzo-3-azabicyclo[3.3.1]nonan-9-ones and α,α'-Bis(substituted benzylidene)cycloalkanones

  • Karthikeyan, Natesan Sundaramurthy;Sathiyanarayanan, Kulathu Iyer;Aravindan, Paduthapillai Gopal
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.11
    • /
    • pp.2555-2558
    • /
    • 2009
  • The condensation of cyclic ketone with aromatic aldehydes in the presence of ammonium acetate under ethanol media affords the corresponding 5-aryl-7,8,13,14-tetrahydrodibenzo[a,i]phenanthridine with excellent yield. This mild and efficient procedure with high yield is also applied to the synthesis of 2,4-diaryl-6,7-benzo-3-azabicyclo- [3.3.1]nonan-9-ones and ${\alpha},{\alpha}{$’-bis(substituted benzylidene)cycloalkanones.

Formal Synthesis of Isocomene

  • Hyo Won Lee;Jae Hyun Lee;Ihl-Young Choi Lee
    • Bulletin of the Korean Chemical Society
    • /
    • v.12 no.4
    • /
    • pp.392-397
    • /
    • 1991
  • A stereocontrolled synthesis of (${\pm}$)-isocomene (1) via selective monoketalization of tricyclo[6.3.0.$0^{1.5}$]undeca-4,7-dione(13) was reported. Grignard reaction of bicyclic enone 10, which was prepared from 2-methyl-1,3-cyclopentadione, gave the 1,4-addition product 11. The subsequent aldol condensation product 12 was converted to mesyl derivative 13. Transformation from 13 to the desired product 19 was achieved by a series of reactions, i.e., the selective monoketalization at C-4 carbonyl group, the elimination of a mesyl group, Birch alkylation, methylation at C-6, the reduction of carbonyl group, the dehydration of alcohol 18, and hydrolysis of the ketal group.