• Bulletin of the Korean Chemical Society
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• 제12권5호
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• pp.517-520
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• 1991

The reaction of dichlorophenylvinylsilane with tert-butyllithium in hydrocarbon solvents at room temperature or below generated the Z and E-isomers of 1-chloro-1-phenyl-2-neopentylsilene. The intermediates were trapped by cyclopentadiene, anthracene and methoxytrimethylsilane to give a consistent 90/10 ratio for the Z-silene to E-silene adduct. This result was interpreted as an evidence for stereochemical induction in the silene generation reaction.

• 분석과학
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• 제14권4호
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• pp.300-305
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• 2001

이소프렌에 불순물로 존재하는 삼중결합 화합물 및 컨쥬게이트된 이중결합 화합물의 함량을 GC/MS를 이용하여 측정하였다. 각 불순물들에 대해 검량곡선은 $1.0-50{\mu}g/mL$과 0.5-5.0%의 농도 범위에서 $R^2=0.996$ 이상의 직선성을 나타내었고 검출한계는 $0.1{\mu}g/mL$ 미만이었다. 시약용 이소프렌의 경우 cis- 및 trans-pipetylene, cyclopentadiene 그리고 dicyclopentadiene은 $1{\mu}g/mL$ 이하의 미량의 농도로 존재했고, isopropenyl acetylene과 2-butyne은 $10-50{\mu}g/mL$의 농도로 측정되었다. 또한 C5 유분을 두 번 정제하여 얻은 이소프렌을 분석한 결과, 시약용 이소프렌에 해당하는 순도를 갖고 있음을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.533-538
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• 2004

Canonical sampling method has been presented to generate the initial conditions for reactive flux studies of organic reactions in water. Velocity Verlet version of Nose-Hoover chain dynamics algorithm has been employed to sample the initial conditions according to canonical distribution. The unstable normal mode of a transition state has been introduced to define a dividing plane separating reactant and product regions in reaction processes. This method has been implemented and tested for the case iels-Alder reaction of methyl vinyl ketone (MVK) and cyclopentadiene (CPD) in water, providing a reliable tool for further reactive flux molecular dynamics studies in condensed media.

• Macromolecular Research
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• 제14권1호
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• pp.107-113
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• 2006

Processible norbornene copolymers were realized by judiciously designing norbomene comonomers, which were themselves prepared by the Diels-Alder reaction of cyclopentadiene and benzoquinone followed by the isomerization and alkylation of alcohols. The norbornene copolymers containing these derivatized comonomers, prepared by [Pd($x_{2}CH-{3} $)$_{4}$][$SbF_{6}$]$_{2}$ catalyst, exhibited excellent solubility in many organic solvents as well as good thermal stability, as evidenced by their high glass transition ($T_{g}$) and decomposition ($\∼$350$^{circ}C$) temperatures. In addition, fairly strong adhesion to substrates such as glasses and silicon wafers was also achieved with these copolymers to overcome the limitations experienced by polynorbornene homopolymers and to make them attractive for many important industrial applications.

• 대한화학회지
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• 제13권1호
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• pp.83-88
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• 1969

By the three-step synthesis of alkyltropolone from five-membered cyclopentadiene, as described in Part Ⅰ, methyltropolone has been prepared. From the hydrolysis product of dichloroketene-methylcyclopentadiene cycloadduct, ${\beta}$-(Ⅰ) and ${\gamma}$-methyltropolone (Ⅱ) were separated, with the first predominating, by means of repeated fractional recrystallization and fractional vacuum sublimation. The total yield of these methyltropolones in the hydrolysis step was about 40%. Comparison of this result with those obtained in part Ⅰ revealed the following order as the relative readiness of their preparation: tropolone > methyltropolone > ethyltropolone. The reason for formation of the isomeric (Ⅱ) was discussed by an interpretation of NMR spectrum of cycloadduct in the unsaturation and methylgroup region.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 추계학술대회
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• pp.265-268
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• 2004

Methyl methacrlate와 cyclopentadiene을 반응하여 Methyl 5-methylbicyclo(2.2.1)hept-2-ene-5-carboxylate(MMBHC)를 합성코자 하였다. 합성된 MMBHC의 온도, solvent 변화와 촉매($AlCl_3$)의 사용 유무에 따른 endo, exe의 비율을 관찰하였다. 온도가 낮은 경우 온도가 높은 쪽 보다 endo 비율이 높았고 촉매($AlCl_3$)를 사용하였을 때(약 endo : exo = 63 : 37) 촉매를 사용하지 않은 반응(endo : exe = 34 : 66)보다 endo의 비율이 높았다. methyl acrylate를 사용한 경우 같은 조건에서 endo : exe의 비율이 93.5 : 6.5로 MMA를 사용한 경우보다 endo의 비율은 좋았다. 온도가 높은 경우 수율은 좋았지만 exe의 비율이 높았고 solvent에 따라 endo, exe의 선택도는 큰 차이를 보이지 않음을 알 수 있었다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2008년도 춘계학술발표논문집
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• pp.323-325
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• 2008

Ethyl methacrylate와 cyclopentadiene을 반응하여 Ethyl 5-methylbicyclo[2.2.1]hept-2-ene-5-carboxylate (EMBHC)를 합성하고 만들어진 EMBHC를 Column Chromatography를 이용하여 endo와 exo를 분리해 GC를 이용하여 그 비율을 측정하였고 $^1H$-NMR을 이용하여 endo와 exo 화합물의 구조를 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1679-1684
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• 2011

Interfacial reactions kinetics often differ from kinetics of bulk reactions. Here, we describe how the density change of an immobilized reactant influences the kinetics of interfacial reactions. Self-assembled monolayers (SAMs) of alkanethiolates on gold were used as a model interface and the Diels-Alder reaction between immobilized quinones and soluble cyclopentadiene was used as a model reaction. The kinetic behavior was studied using varying concentrations of quinones. An unusual threshold density of quinones (${\Gamma}_c$ = 5.2-7.2%), at which the pseudo-first order rate constant started to vary as the reaction progressed, was observed. This unexpected kinetic behavior was attributed to the phase-separation phenomena of multi-component SAMs. Additional experiments using more phase-separated two-component SAMs supported this explanation by revealing a significant decrease in ${\Gamma}_c$ values. When the background hydroxyl group was replaced with carboxylic or phosphoric acid groups, ${\Gamma}_c$ was observed at below 1%. Also, more phase-separated thermodynamically controlled SAMs produced a lower critical density (3% < ${\Gamma}_c$ < 4.9%) than that of the less phaseseparated kinetically controlled SAMs (6.5% < ${\Gamma}_c$ < 8.9%).

• 공업화학
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• 제8권1호
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• pp.8-15
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• 1997

바니린을 Curie-point pyrolyzer-GC/MSD 장치를 사용하여 920, 740, 500, $333^{\circ}C$에서 각각 열분해하고, 열분해 생성물을 분리 및 확인하였다. 확인된 성분중에서 $920^{\circ}C$에서는 95개 성분, $740^{\circ}C$에서는 40개 성분, $500^{\circ}C$에서는 17개 성분, $333^{\circ}C$에서는 11개 성분을 확인할 수 있었으며 이 열분해 반응생성물 중 주요 생성물인 벤젠, 페놀, 2-히드록시 벤즈알데히드, 2-메톡시페놀, 4-메톡시벤즈알데히드, 벤즈알데히드, 메톡시벤젠, 1,3-시크로펜타디엔 등은 바니린의 작용기가 해리되었거나, 분해된 생성물로 생각되며, 1,3-benzodioxole-5-carbox-aldehyde, 메틸벤젠, 스틸렌, 메틸페놀 등은 $500^{\circ}C$ 이하에서도 바니린의 메톡시 작용기가 해리되어 생성되는 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.233-237
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• 2005

Cyclopentadiene compounds, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 2) and 2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 3; R = ph, R' = ph, 4; R = 2-naphthyl, R' = H, 5) are readily synthesized from 2-bromo-3-methoxy-1,3-dimethylcyclopentene (1). Reaction of the cyclopentadienes with Ti(NMe$_2$)$_4$ in toluene results in clean formation of the cyclopentadienyl tris(dimethylamido)titanium complexes, which are transformed to the trichloride complexes, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 6) and {2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 7; R = ph, R' = ph, 8; R = 2-naphthyl, R' = H, 9). Attempts to form C1-bridged Cp/oxido complexes by elimination of MeCl or Me$_3$SiCl were not successful. X-ray structures of 6, 7 and an intermediate complex {2-[Ph$_2$C(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_2$(NMe$_2$) (10) were determined.