• 약학회지
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• 제29권2호
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• pp.103-106
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• 1985

Reaction between 2-aminobenzamide and thionylchloride gave benzo-2-this-1,3[2H]-diazine-4-one-2-oxide (I) at room temperature. With other carbonyl derivatives quinazoline-4-one derivatives (II-VIII) were obtained.

• Bulletin of the Korean Chemical Society
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• 제11권4호
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• pp.307-309
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• 1990

The stereoselectivity of the reaction between methyl vinyl ketone dimer, which contains two possible sites of chelation, and zinc borohydride or diisobutylaluminum hydride has been studied in order to illuminate the factors involved in the high levels of asymmetric induction obtained in the bicyclic system. The conditions for the formation of the exo-5,7-dimethyl-6,8-dioxabicyclo[3.2.1]octane are DIBAH reduction of MVK dimer in ether at reflux followed by acidic cyclizatioan, and for the endo isomer are $Zn(BH_4)_2$ reduction with $ZnCl_2$ at $0^{\circ}C.$.

• 폴리머
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• 제34권2호
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• pp.159-165
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• 2010

리빙 음이온 중합에 의해 sec-BuLi으로 개시된 polystyryllithium (PSLi)과 polybutadienyllithium (PBDLi)의 연쇄 말단에 di(2-pyridyl)ketone(DPK)을 반응시켜 dipyridine이 말단 관능화된 폴리스티렌과 폴리부타디엔을 각각 합성하였다. 분자량이 1000~2000 g/mol인 PSLi과 PBDLi을 사용하여 TMEDA 존재하에서 말단 DPK-관능화 반응 후 GPC에 의한 분자량 특성분석과 $^1H$-NMR, $^{13}C$-NMR 분석에 의한 고분자 말단 구조 분석을 통하여 말단 관능화 수율과 함께 유기리튬의 피리딘 링 친핵성 부가 반응으로 인한 커플링 현상을 확인하였다. PBDLi에 DPK를 부가하는 일반적인 말단 관능화 방법에 비하여 역으로 부가하는 방법에서 최대 9% 정도의 커플링 정도와 86% 이상의 관능화 수율을 보였다. 이 반응에서 LiCl 첨가효과는 없었으며, 반응온도가 낮을수록 높은 관능화 수율을 나타내었다.

• 대한화학회지
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• 제50권3호
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• pp.183-189
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• 2006

초음파를 이용한 응축 반응을 이용하여 다양한 치환기가 붙은 4-methoxy-1-naphthyl ketone화합물들을 90% 이상의 높은 수율로 합성하였으며, 생성된 화합물물들을 미세 분석법, IR, 1H, 13C NMR 분석법 등을 이용하여 확인하였다. IR 스펙트럼에서 s-cis와 s-trans C=O stretching 모드를 확인하였으며, NMR 데이터로부터 에틸렌의 탄소와 수소에 대한 chemical shift를 확인하였다. 이러한 분광데이터를 이용하여 여러 분자들에 대한 Hammet 치환기 상수 값 들을 얻을 수 있었으며, 이들로부터 가용매 분해반응에 미치는 치환기 효과를 해석할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제4권1호
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• pp.14-17
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• 1983

The effects of trialkylborane on the stereochemistry of ketone reduction with lithium borohydride were studied for the four representative ketones, namely 4-t-butylcyclohexanone, 2-methylcyclohexanone, norcamphor, and camphor. The presence of trialkylborane increased the yields of the less stable alcohols. For example, in the presence of tri-s-butylborane, 42 % yield of cis-4-t-butylcyclohexanol was observed whereas only 8 % yield with lithium borohydride alone in the reduction of 4-t-butylcyclohexanone. The in situ formation of lithium trialkylborohydride, by the hydride transfer from lithium trialkoxyborohydride to trialkylborane, was demonstrated as a possible mechanism for the catalytic effect of trialkylborane.

• 한국안전학회지
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• 제10권2호
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• pp.92-96
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• 1995

The flash point is generally used as a hazardous index of fire or explosion of a flammable liquid. In this study, the lower flash points and the upper flash points according to the composition of Toluene-o-Xylene and Toluene-Methyl Ethyl Ketone mixtures are determined by air-blowing method. As results, relations between the flash points and the compositions of mixtures ; (1) for Toluene-o-Xylene mixtures $T_{fL}$=25.23 $\alpha$ ＋5.34 $T_{fu}$=27.36 $\alpha$ ＋40.50 (2) for Toluene-Methyl Ethyl Keton mixtures $T_{fL}$=10.00 $\beta$-5.00 $T_{fu}$=16.91 $\beta$＋20.45.

• 한국산업보건학회지
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• 제5권1호
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• pp.104-118
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• 1995

This study was performed to evaluate factors affecting desorption of organic solvents collected on charcoal tube and to find out the optimum condition. Desorption efficiency for polar analytes was improved when several polar desorption solvents such as methanol, dimethylformamide(DMF), 2-(2-butoxyethoxy)ethanol were added to carbon disulfide($CS_2$). The best improvement was achieved when 10% dimethylformamide(DMF) in $CS_2$ was used as desorption solvent. During storage of polar analytes, recovery was greatly reduced. Especially, the recovery of cyclohexanone was decreased to 18.1 % after a month storage at $34^{\circ}C$. After two weeks storage, recovery of polar analytes was sharply decreased. Water adsorbed on charcoal interfered the recovery of polar analytes but didn't interfere that one of nonpolar solvent, toluene. When 10% DMF in $CS_2$ was used as desorption solvent, the effect of water on recovery was decreased, comparing with Desorption efficiency increased when analyte loading increased, and usage of 10% DMF in $CS_2$ decreased the loading effect. Increasing volume of desorption solvent was not effective to improve desorption efficiency of analytes when 10% DMF was used. Continuous shaking and sonication is not helpful to increase the desorption efficiency of analytes except cyclohexanone using 10% DMF. When silica gel used as adsorbent, methanol was better desorbent than dimethylsulfoxide. Analytes adsorbed on silica gel showed high recovery in low concentration and less affected by humidity. On the basis of this study, the following conclusions have been drawn. To improve the recovery of polar organic materials in air samples, it is necessary to analyze samples as soon as possible after they were collected. Otherwise, samples must be stored at low temperature. Using two components of desorption solvents, such as 10% DMF in $CS_2$, the effects of loading and humidity decreased for polar analytes such as methyl ethyl ketone and methyl isobutyl ketone. When work place has high humidity with low concentration of polar organic solvents, silica gel can be used as adsorbent, because it produces quantitative recovery for polar analytes at this condition. But it should be noted that high humidity makes breakthrough easy in silica gel samples.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.416-421
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• 1995

The approximate rates and stoichiometry of the reaction of excess lithium gallium hydride with selected organic compounds containing representative functional groups were examined under the standard conditions (diethyl ether, 0 $^{\circ}C)$ in order to compare its reducing characteristics with lithium aluminum hydride and lithium borohydride previously reported, and enlarge the scope of its applicability as a reducing agent. Alcohols, phenol, and amines evolve hydrogen rapidly and quantitatively. However lithium gallium hydride reacts with only one active hydrogen of primary amine. Aldehydes and ketones of diverse structure are rapidly reduced to the corresponding alcohols. Conjugated aldehyde and ketone such as cinnamaldehyde and methyl vinyl ketone are rapidly reduced to the corresponding saturated alcohols. p-Benzoquinone is mainly reduces to hydroquinone. Caproic acid and benzoic acid liberate hydrogen rapidly and quantitatively, but reduction proceeds slowly. The acid chlorides and esters tested are all rapidly reduced to the corresponding alcohols. Alkyl halides and epoxides are reduced rapidly with an uptake of 1 equiv of hydride. Styrene oxide is reduced to give 1-phenylethanol quantitatively. Primary amides are reduced slowly. Benzonitrile consumes 2.0 equiv of hydride rapidly, whereas capronitrile is reduced slowly. Nitro compounds consumed 2.9 equiv of hydride, of which 1.9 equiv is for reduction, whereas azobenzene, and azoxybenzene are inert toward this reagent. Cyclohexanone oxime is reduced consuming 2.0 equiv of hydride for reduction at a moderate rate. Pyridine is inert toward this reagent. Disulfides and sulfoxides are reduced slowly, whereas sulfide, sulfone, and sulfonate are inert under these reaction conditions. Sulfonic acid evolves 1 equiv of hydrogen instantly, but reduction is not proceeded.

• Korean Chemical Engineering Research
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• 제57권1호
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• pp.17-21
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• 2019

산화환원흐름전지(Redox Flow Battery, RFB)는 대용량 에너지 저장장치로 바나듐 산화환원흐름전지가 대표적인 RFB인데, V-RFB는 고가인 점이 문제다. 철-크롬 RFB는 저가의 활물질(철, 크롬)을 사용해 경제적인 점이 장점인데, 성능이 낮은 점이 해결해야 할 과제다. 낮은 성능의 한 원인이 활물질의 크로스오버인데, 본 연구에서 불소계막 대신 탄화수소계막인 sulfonated Poly (ether ether ketone) (sPEEK)막을 사용해 활물질 투과를 감소시키는 연구를 하였다. sPEEK막의 크롬 이온 투과도는 $1.8{\times}10^{-6}cm^2/min$으로 Nafion막에 비해 약 1/33으로 작아서 불소계막 대신 sPEEK막을 사용하면 높은 활물질 투과문제를 해결할 수 있음을 보였다. 철 이온의 sPEEK막 확산의 활성화 에너지도 24.9 kJ/mol으로 Nafion막의 약 66%로 작았다. 그리고 고분자막에 들어간 e-PTFE 지지체가 철-크롬 산화환원흐름전지(ICRFB)에서 활물질 투과도를 감소시킴을 보였다.

• 환경생물
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• 제35권2호
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• pp.169-174
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• 2017

화학사고 발생 시 환경에 노출된 화학물질이 생태계에 미치는 영향을 평가하기 위하여, 우리나라에서 서식하는 김어리톡토기(Paronychiurus kimi)를 이용하여 OECD guidelines 232 Collembola reproduction test in soil에 따라 사고대비물질 2종, 메틸에틸케톤과 메탄올에 대한 급성, 만성 생태독성평가를 진행하였다. 메틸에틸케톤과 메탄올을 농도별로 OECD 인공토양과 섞은 후, 성충 P. kimi 10마리를 접종하여 7일 후의 성충 사망률과, 28일 후의 성충 사망률 및 번식률을 확인하였다. 메틸에틸케톤과 메탄올에 대한 급성독성평가 결과, $LC_{50}$ 값은 각각 2378과 $762mg\;kg^{-1}$ soil이었으며, 만성독성평가 결과, $LC_{50}$ 값은 각각 1857과 $6063mg\;kg^{-1}$ soil이었다. 만성독성평가 시 P. kimi의 산란 수에 대한 $EC_{50}$ 값은 메틸에틸케톤에서 $570mg\;kg^{-1}$ soil, 메탄올이 $589mg\;kg^{-1}$ soil로 통계적으로 유의한 차이를 보이지 않았다. 본 연구의 결과 P. kimi가 종래의 다른 토양 절지동물에 비해 메탄올에 대해 높은 민감도를 갖는 것으로 판단되었다. 현재까지 이들 사고대비물질에 대한 생태독성정보의 부재와 더불어 대부분의 사고대비물질들이 큰 휘발성을 가지고 있는 점을 감안할 때, 이러한 사고대비물질에 대한 정확한 평가를 위해서는 종래의 표준지침을 개선하거나 새로운 평가지침 마련을 통해 지속적인 생태독성정보구축을 위한 더 많은 연구가 필요하다.