• 대한화학회지
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• 제43권3호
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• pp.302-306
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• 1999

Quinoxaline 4-oxide 10을 2-chloroacrylonitrile과 반응시켜 1,3-쌍극성 고리화 첨가반응으로 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxaline류 11a, b를 합성하였고, 이들을 2,3,4,6-tetrahydro-1H-1,2-diazepino-[3,4-b]quinoxaline 12로 변환시켰다. 그리고 ??嵐?11a를 아세트산/물 용매에서 SeO2와 반응시켜서 고리변환에 의해 1,4-dihydro-4-oxopyridazino[3,4-b]quinoxaline 13을 합성하였다.

• Korean Chemical Engineering Research
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• 제48권5호
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• pp.621-626
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• 2010

본 연구에서는 이미다졸계의 이온성액체를 폴리스티렌계 고분자에 고정화시킨 촉매를 제조하고, 알릴글리시딜에테르(AGE)와 이산화탄소의 부가반응을 통한 알릴글리시딜카보네이트의 합성반응에서 이 촉매의 반응특성을 고찰하였다. 고정화된 이온성액체는 공중합된 폴리스티렌계 고분자에 이미다졸이 고정화됨으로써 형성되었다. 제조된 촉매에 대해서 EA, FT-IR, TGA 그리고 SEM 등 다양한 기기분석을 통하여 특성분석을 수행하였다. 고정화된 이온성액체 촉매는 반응온도 $120^{\circ}C$, 이산화탄소 압력 1.48 MPa에서 AGE 전환율이 80%이고 생성물의 선택도가 96% 이상으로 우수한 반응성을 나타내었다. 또한 고정화된 이온성액체 촉매는 4회 연속 사용하여도 초기의 활성이 크게 감소하지 않아 안정성이 좋은 것으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제19권3호
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• pp.340-344
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• 1998

A facile synthesis of 4,5-(1',2'-diphenylethylenedithio)-1,3-dithiole-2-thione (dPhEDT-DTT) is carried out via a Diels-Alder type [2+4] cycloaddition reaction of 1,3-dithiol-2,4,5-trithione oligomer and t-stilbene. Molecular structure of dPhEDT-DTT is determined by x-ray crystallography: space group P1, a=11.694(3) Å, b=12.117(3) Å, c=14.688(3) Å, α=113.12(2)°, β=102.23(2)°, γ=107.02(2)°, V= 1699.1(7) Å3, Z=2. It turns out that dPhEDT-DTT crystallizes as a racemic compound consisting of (R,R) and (S,S) enantiomers. Coupling reaction of dPhEDT-DTO undergone in neat P(OEt)3 yields TTF(SEt)4 instead of ET derivative. When PR3 (R=OEt, OPh, Ph) is used in benzene, toluene or xylene, however, dPhEDT-DTO is decomposed.

• Bulletin of the Korean Chemical Society
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• 제18권6호
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• pp.604-608
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• 1997

Reactions of arenealdehyde 2-pyridylhydrazones (1) with thianthrene cation radical ($Th^{+·}$) and tris(2,4-dibromophenyl)aminium hexachloroantimonate ($Ar_3N^{+·}SbCl_6^-$) were investigated. The major product was switched depending on the cation radical being used. That is, s-triazolo[4,3-α]pyridines (2), an intramolecular cyclization product, and 1-(2-pyridyl)-1,2,4-triazoles (3), an intermolecular cycloaddition product, were obtained as a major product when reacted with $Th^{+·}$ and $Ar_3N^{+·}$, respectively in nitrile solvents. The plausible mechanisms are proposed based on both the reduction potentials of $Th^{+·}$ and $Ar_3N^{+·}$ and control experiments.

• Bulletin of the Korean Chemical Society
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• 제28권5호
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• pp.763-766
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• 2007

Oxypalmatine and oxypseudopalmatine were synthesized in three steps from the benzonitrile 11 and toluamides 12a, b. The lithiated cycloaddition reaction yielded 3-arylisoquinolinone intermediates. A subsequent internal SN2 reaction produced the corresponding 8-oxoprotoberberines, oxypalmatine and oxypseudopalmatine.

• Bulletin of the Korean Chemical Society
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• 제18권5호
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• pp.534-540
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• 1997

4H,6H-Furo[3,4-c]isoxazoles (Ⅰ-Ⅳ), potential fungicides, have been designed and synthesized via intramolecular [2+3] cycloaddition of nitroalkyne 3 as a key step. The broad spectrum of fungicidal activities of furoisoxazoles (Ⅰ-Ⅳ) were observed on plant pathogens at 250 ppm. Furoisoxazoles Ⅱ, Ⅲ with chlorophenyl at 6-position and methyl or alkylated oxime group at 3-position gave effective control of plant diseases. The furoisoxazole Ⅳ with a chlorophenyl group at 4-position also resulted in high fungicidal activities.

• Bulletin of the Korean Chemical Society
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• 제4권5호
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• pp.197-200
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• 1983

The Diels-Alder cycloaddition reactions between dienes and allenic ketones were studied theoretically using CNDO/2 method. It was found that the reaction is a neutral electron demand type with matrix element control and the reactivity, the regio- and stereo-selectivities can be correctly predicted based on interaction energies calculated with the 4-center FMO formalism.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.65.1-65.1
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• 2003

Natural benzo[c]phenanthridine and protoberberine alkaloids which have been attractive to synthetic organic chemists and biochemists over the last 2 decades since such compounds have shown interesting biological properties such as antitumor, antiviral and antimicrobacterial activities. For the systematic research on these alkaloids, several total syntheses of these alkaloids have been reported. However, the bulk of reported benzo[c]phenanthridine synthetic studies to date have involved multistep sequences for assembly of the target molecules as well as lack of generality for synthesizing substituted molecules. (omitted)

• Bulletin of the Korean Chemical Society
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• 제9권3호
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• pp.176-179
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• 1988

3-Methoxy-4-cyano-2,9-dioxabicyclo[4.3.0]non-3-e ne (1) was prepared by (4 + 2) cycloaddition reaction of methyl ${\alpha}$-cyanoacrylate with 2,3-dihydrofuran. Compound 1 was ring-open polymerized by cationic catalyst such as boron trifluoride etherate to obtain alternating head-to-head (H-H) copolymer (2) of methyl $\alpha$ -cyanoacrylate and 2,3-dihydrofuran. For comparison, head-to-tail (H-T) copolymer (3) was also prepared by free radical copolymerization of the corresponding monomers. The H-H copolymer exhibited minor differences in its $^1H$-NMR and IR spectra, but in the $^{13}C$-NMR spectra significant differences were observed between the H-H and H-T copolymers. All of the H-H and H-T copolymers were soluble in common solvents and the inherent viscosities were in the range 0.2-0.3 dl/g.

• 대한화학회지
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• 제45권4호
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• pp.318-324
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• 2001

6-Chloro-2-hydrazinoquinoxaline(4) 또는 6-chloro-hydrazinoquinoxaline 4-oxide(7)를 alkyl(ethoxymethylene)cyanoacetate류와 반응시켜 prazolylquinoxaline류(5,8)를 합성하였다. 그리고 화합물 8을 dimethyl acethylenedicarboxylate와 반응시켜 1,3-쌍극성 고 리와 첨가반응과 고리변환에 의하여 pyrazolylpyrrolo[1,2-a]quinoxaline류(9)를 합성하였다.