• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.503-507
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• 2006

The rhodium(II)-catalyzed reactions of diazo compound derived from Meldrum's acid with a variety of styrenes have been examined. These reactions provide a rapid route to the preparation of cyclopropanes with a variety of substituents on the benzene ring. The mechanistic pathway for the formation of these products has been also described in terms of a stepwise mechanism.

• The Korean Journal of Food And Nutrition
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• v.7 no.1
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• pp.29-35
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• 1994

Photolysis of diazotetracyanocyclopentadiene has been investigated by means of IR and UV-vis spec troscopy in Ar matrix. Parent carbene is produced in low yield and could be detected by UV-vis spectroscopy and IR spectroscopy. The carbene produced from the diazo compound is very photolabile and also decay thermally at temperature as low as 10K. When the diazo compound is photolyzed the Arrhenius plots show a tunneling effect that is not shown as non linearity.

• Textile Coloration and Finishing
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• v.19 no.5
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• pp.37-40
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• 2007

The electrostatic layer-by-layer technique provides a convenient way to control the construction of ultrathin films at nano-scale ranges and can be easily obtained. It can be also applicable to fiber substrate with dye compounds. We have fabricated multilayer dye films using diazonium resin and three couplers, which are prepared by self-assembly approach. This method is based on layer-by-layer deposition using electrostatic attraction between oppositely charged ions. Beside, the diazo coupling reaction proceeded to form azo dye layer on the PET fibers the same time. The corresponding results of the multilayer films have been discussed on the level of color strength (K/S).

• Bulletin of the Korean Chemical Society
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• v.18 no.9
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• pp.945-952
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• 1997

The reactions of diazoindanes and diazoindanones with triphenylphosphine have been studied in acetonitrile. The diazoindanes and diazoindanones react with triphenylphosphazine. The reaction of 1,3-bis(diazo)indan-2-one with a tenfold excess of triphenylphosphine in dry acetonitrile gave the 1,3-bis(phosphazino)indan-2-one, however in acetonitrile containing below of 1% water, the 1,3-bis(hydrazono)indan-2-one was produced by hydrolysis. The phosphazine compound could be easily converted into bishydrazone by recrystallization, due to small amounts of water in the solvent. The reactivity of triphenylphosphine toward diazoindanes and diazoindanones depends on the structrue of the diazo compounds.

• YAKHAK HOEJI
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• v.59 no.2
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• pp.66-69
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• 2015

A concise synthesis of flurbiprofen, a member of the non-steroidal anti-inflammatory 2-arylpropionic acids, has been accomplished. The key feature of this synthesis involves successive palladium-catalyzed cross coupling reactions. In particular, a 2-arylacylate intermediate, which easily converted to the key 2-arylpropionic acid scaffold, was afforded by a versatile palladium-catalyzed cross coupling reaction between diazopropanate and bisphenylboronic acid. This synthetic procedure would facilitate synthesis of the flurbiprofen and anti-inflammatory 2-arylpropionic acid derivatives.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.111-124
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• 2013

Jianbo Wang의 그룹에서 최근 발표한 무촉매 분자 내 탄소-탄소 결합 형성 반응의 메커니즘을 계산 화학적으로 평가한다. 이 반응은 금속 촉매를 사용하지 않는다는 점과 Bio activity 를 갖는 Hydroxy-substituted Polycyclic Aromatic Compound (PAC)를 손쉽게 합성할 수 있다는 점에서 중요하다. Diazo moiety를 갖는 분자의 반응이 일반적으로 진행할 수 있는 세 가지 반응 경로가 제시되었고, DFT functional을 이용해 중간체 및 전이 상태에 대한 최적화 구조 및 에너지를 얻었다. 탄소-탄소 결합의 원천을 탐구하기 위해 Natural bond orbital charge calculation과 치환기 효과에 대한 계산이 수행되었다. 계산 결과, 중간체로 Triplet carbene을 형성하는 경로가 가장 불안정한 중간체를 형성했고, Tosylate가 해리되기 전 탄소-탄소 결합이 형성되는 경로가 가장 합리적인 반응경로임을 알 수 있었다.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.148-152
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• 2008

Coated filters were developed to replace the glass impinger methods that use reagent solutions. The purpose of this study was to simultaneously measure nitrogen dioxide ($NO_2$) and respirable suspended particles (RSP) by a filtration method with a cyclone connected to a pump. A first pre-filter for RSP and second filter for $NO_2$, which was soaked in a TEA (Triethanolamine) solution, were loaded into a filter cassette with a pump flow rate of 1.7 l/m. After sampling, the TEA soaked filter was removed from the cassette, placed in a large test tube (10 ml), mixed, and allowed time to develop. The absorbance (abs) of the diazo compound of the $NO_2$ and N-(1-Napthylethylenediamine dihydrochloride) in the color reagent was measured at 545 nm on a spectrophotometer. The collection efficiency(%) of $NO_2$ by each 3 filter soaked in TEA solution and used in the cyclone with a pump flow rate 1.7 l/m was $89{\pm}3%$ and the correlation coefficient between the true $NO_2$ concentration and that determined by the TEA soaked filters was 0.993(p<0.001).