• Analytical Science and Technology
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• v.5 no.4
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• pp.373-379
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• 1992

The pyrolysis conditions for the thermal isomerization products of pinane were carried out by the furnace type pyrolyzer and the curie-point pyrolyzer equipped with gas chromatograph and mass spectrometer. It was confirmed that curie-point type is much better furnace type, and high yield (70%) of citronellene was obtained from pinane as the main isomerization product under the best conditions by curie-point type. The optimum conditions of pyrolysis are $590^{\circ}C$ for 4 sec. and the major products were indentified as citronellene, m-Menth-6-ene, m-Menth-1-ene and 1-Methyl-4-(1-methylethylidiene) cyclohexane.

• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.411-420
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• 1991

The dehydrocyclization of n-heptane was studied over $Pt-Sn/{\gamma}-Al/_2O_3$ catalysts with varying Sn content in a fixed bed continuous flow reactor. The range of experimental conditions was at the temperature between 450 and $550^{\circ}C$, the pressure $20{\times}10^5-50{\times}10^5Pa$, the contact time 0.09 and 0.27 hr and the $H_2/H.C$. mole ratio 10. The conversion and selectivity of dehydrocyclization increased with increasing temperature, but decreased with increasing pressure. When we use Sn as a promoter, the selectivity of dehydrocyclization changesa a little, but the conversion was increased and the selectivity of isomerization increased a lot. The activation energy of dehydrocyclization of n-heptane was 34.5 kcal/mol over 0.6 wt % Pt-0.6 wt % $Sn/{\gamma}-Al_2O_3$.

• Journal of the Korean Chemical Society
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• v.23 no.3
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• pp.132-135
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• 1979

The thermal decomposition of a dilute mixture of 1,1,2,2,-$C_2H_2F_4$ in argon has been investigated in a single-pulse shock tube between 1146 and $1232^{\circ}K$ at total reflected shock pressures of about 3000 torr. Under these conditions the reaction proceeds exclusively by the molecular elimination of hydrogen fluoride. It has been found that the asymmetric isomer with the fully fluorinated ${\alpha}$-carbon requires the higher activation energy which may be attributed to the difference in atomic charge densities between isomers. The rate constant ratio is given by $log(k_1/k_2) = -0.069 {\pm} 0.021 ＋(1388{\pm}113) / 2.303RT$ in good agreement with previous independent studies.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.127-139
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• 2014

Hard-Soft Acid-Base (HSAB) 이론은 일반적인 유기, 무기반응의 반응성을 설명하는데 사용되어 왔다. 밀도범함수이론(DFT)을 기반으로 한 계산을 통하여 반응을 기술하기 위해 필요한 화학 퍼텐셜, global/local hardness/softness와 Fukui 함수 등을 얻을 수 있다. B3LYP 수준 하에서 DFT 양자계산을 이용하여 유기 반응을 분석했을 때 local HSAB 이론의 적용여부와 장단점을 알아보고자 하였다. 1-subtituted 다이엔과 비대칭 친다이엔체를 이용한 딜스-알더 반응의 경우 local HSAB 이론을 적용시켜, 오쏘 이성질체가 주 화합물인 이유를 설명할 수 있었다. 작용기를 변화시켰을 때 나타나는 차이점에서 규칙적인 경향성을 볼 수 없다는 사실을 통해서 전자, 입체 효과로 딜스-알더 반응을 분석할 수 없었던 이유를 이해할 수 있었다. Thiocyanate 음이온의 알킬화 반응의 경우 local HSAB 이론을 적용시켰을 때, 얻은 값을 통해서 반응 지점의 선호도를 예측할 수 없었는데 이는 thiocyanate를 생성하는 반응이 속도론적 지배 하에서 우세하는 반응이기 때문이다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.146-149
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• 1998

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.04a
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• pp.90-93
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• 1998

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.465-471
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• 1985

The rate constants for the solvolysis of anthraquinone-2-carbonyl chloride in binary solvent mixtures, methanol-acetonitrile, methanol-acetone, ethanol-acetonitrile and ethanol-acetone, have been studied by means of conductometry. Maximum rate phenomena were observed at the methanol mole fraction, $X_{MeOH}$ = 0.73~0.81 for methanol-acetonitrile and at $X_{MeOH}$ = 0.83 for methanol-acetone mixtures. The Kivinen and Grunwald-Winstein plots indicated that the reaction proceeds via $S_N2$ type mechanism. Application of Taft's solvatochromic correlation on the solvolysis rate revealed that both $\alpha$ and ${\pi}^*$ are important for reactions in methanol-acetonitrile and methanol-acetone mixtures, while only ${\alpha}$ influences significantly on the rate in ethanol-acetonitrile and ethanol-acetone mixtures.

• Journal of the Korean Chemical Society
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• v.28 no.1
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• pp.20-25
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• 1984

Sodamide-containing complex base induced dehydrohalogenations from trans-1,2-dihalocyclohexanes were investigated. Isomerization, deuterium isotope effect along with element effect and others provided strong evidence in favor of E2 reaction mechanism.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.174-176
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• 2010

• Journal of the Korean Chemical Society
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• v.29 no.3
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• pp.287-294
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• 1985

Acrylamide, N-alkyl substituted acrylamides and N,N-diethylacrylamide were reacted with aryl bromides in the presence of triethylamine and palladium acetate-triorthotolyl phosphine catalyst to form the various substituted aryl conjugated enamides. These reactions proceeded selectively and (E)-isomer of aryl conjugated enamides was obtained. N-alkyl substituted acrylamides were more reactive than acrylamide or N,N-diethylacrylamide and gave high yields of vinylated products. Aryl bromides with electron withdrawing group showed good reactivity but aryl bromides with electron donating group showed poor reactivity or no reactivity for acrylamide or N,N-diethylacrylamide.