• Bulletin of the Korean Chemical Society
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• 제20권1호
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• pp.65-68
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• 1999

Novel mononuclear group 13 metal complexes with the formula (R2M){NC5H4C(CH3)NNC(S)NH(C6H5)} (M=Al, R=iC4H9 (1); M=Ga, R=iC4H9 (2); M=Al, R=CH2SiMe3 (3); M=Ga, R=CH2SiMe3 (4)) result when 2-acetyl pyridine 4-phenyl-thiosemicarbazone ligand is mixed with trialkyl aluminum or trialkylgallium. These compounds 1-4 are characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and singlecrystal X-ray diffraction. X-ray single-crystal diffraction analysis reveals that 1 is mononuclear metal compound with coordination number of 5 and N, N, S-coordination mode.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1211-1216
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• 2008

A series of DTPA-bis(amides) functionalized by pyridine (1a-c) and N-phenylpicolinamide) (1d-e) and their Gd(III)-complexes of the type [Gd(1)($H_2O$)]·x$H_2O$ (2a-e) were prepared and characterized by analytical and spectroscopic techniques. Potentiality of 2a-e as contrast agents for magnetic resonance imaging (MRI CA) was investigated by measuring relevant physicochemical properties and relaxivities and compared with [Gd(DTPA-BMA)($H_2O$)] (DTPA-BMA=N,N''-di(methylcarbamoylmethyl)diethylenetriamine-N,N',N''-triacetate) ($Omniscan^{(R)}$). The R1 relaxivities of aqueous solutions of 2a-c are in the range of 3.33 -5.02 $mM^{-1}$$sec^{-1}$, which are comparable with those of $Omniscan^{(R)}$ (r1=4.58 $mM^{-1}sec^{-1}$). Complexes 2d-e, insoluble in water, exhibit relatively higher R1 values (8.1- 8.3 $mM^{-1}sec^{-1}$) in HP-$\beta$-CD solutions.

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.275-279
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• 1986

Concentration dependences of the isotropic Raman band width and the peak position for the ${\nu}_1$ (C-H stretching) mode of nitromethane in chloroform-d, pyridine-$d_5$, 1,3,5-trifluorobenzene, and hexafluorobenzene have been investigated. For all solutions, the experimental concentration dependences have been well described by the concentration fluctuation model of Knapp and Fischer when appropriate values for the effective numbers (N) of nearest neighbors were used. For the $CH_3NO_2/C_6F_6$ solution, an abnormally small value (2) of N indicates strong intermolecular interaction.

• 대한화학회지
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• 제55권6호
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• pp.940-951
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• 2011

Reaction of 1-methylpyrimidine-(1H,3H,5H)-2,4,6-trione (1-MBA 1) as an unsymmetrical barbituric acid with cyanogen bromide and various aldehydes in the presence of triethylamine and/or pyridine afforded diastereomeric mixtures of new class of heterocyclic stable 5-aryl-1,1'-dimethyl- and 5-aryl-3,1'-dimethyl-1H,1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which are dimeric forms of 1-methyl barbiturate at the range of $0^{\circ}C$ to room temperature. In the reaction of some aldehydes with 1-MBA and BrCN were afforded a mixture of diastereomers. Another two aldehydes such as 4-cyano- and 2-hydroxybenzaldehydes gave exclusively two diastereomers in which binded to the salt of triethylammonium hydrobromide by intermolecular H-bond in ratio of 1:1. 4-Hydroxybenzaldehyde and 2-pyridinecarbaldehyde gave exclusively one diastereomer under the same condition. Aldehydes possessing strong electron-donor were produced exclusively two geometric isomers of Knoevenagel adduct (E- and Z-isomers). The structures of compounds were deduced by $^1H$ NMR, $^{13}C$ NMR and FT-IR spectroscopy. Mechanism of the formation is discussed.

• 대한화학회지
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• 제6권2호
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• pp.148-154
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• 1962

The reactions between organic halides$(CCl_4,\;C_6H_5Br,\;C_6H_5Cl,\;C_6H_5I)$ and amines $(C_6H_5NH_2,\;R_2NH,\;R_3N,\;(CH_2)_5NH,\;pyridine)$ were studied under mixed u.v. irradiation. The modes of reactions were examined by means of gas chromatography and product-reactant ratio determination. The reaction of $CCl_4$ with amines give chloroform and hexachloroethanes, and the reaction of aromatic halides with amines gave biphenyl and benzene. In each series of reaction there obtained mainly corresponding amine hydrohalides, but no amination products. The reactivity was in the order of the basicity of amines and of the reactivity of organic hahides, except in the case of cyclic tertiary amine. The result was interpreted as a non-chain photodecomposition process. A competitive proton abstraction reaction path via the formation of a change transfer complex was proposed as the reaction mechanism.

• KEPCO Journal on Electric Power and Energy
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• 제1권1호
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• pp.169-174
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• 2015

본 연구에서는 그래핀의 인위적인 합성방법인 화학기상증착법을 활용하여 합성 파라미터들을 변화시켜줌으로써 그래핀의 물성을 조절하는 연구를 수행하였다. 먼저, 메탄가스를 탄소원으로 순수 그래핀을 합성하였고, 액상의 피리딘을 원료로 사용하여 질소가 도핑된 그래핀을 합성하였다. 각각의 그래핀의 물성은 라만 분광법, X선 광전자 분광법(XPS)을 통한 기초 광물성 측정과 게이트 전압에 따른 그래핀 채널의 전류-전압 응답특성을 통한 전기적 수송현상 측정에 의해 평가되었다. 메탄가스로 합성된 그래핀의 라만 분광 스펙트럼에서는 G-peak과 2D-peak가 선명히 보였고, XPS에서 C1s-peak가 선명하였고, 아울러 전하중성점은 게이트 전압 약 +4 V 정도에서 나타났다. 피리딘을 원료로 합성된 그래핀의 라만 분광 스펙트럼에서는 D-peak, G-peak 그리고 다소 약해진 2D-peak 등이 보였고, XPS에서는 C1s-peak은 물론 N1s-peak도 나타났으며, 전하중성점은 게이트 전압 약 -96 V 정도에서 나타났다. 결과적으로 우리는 화학기상증착법을 활용하여 그래핀의 물성을 성공적으로 조절하였다.

• 약학회지
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• 제41권5호
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• pp.554-558
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• 1997

Two alkaloidal components were isolated from the ether soluble part of the MeOH extract of the root bark of Euonymus japonica. Their structures were elucidated by the spe ctroscopic analylses as the sesquiterpene pyridine alkaloids derived from polyester sesquiterpenes which are characteristically detected in Celastraceae plants. These include macrocycle formed by two ester linkages between dihydro-${\beta}$-agarofuran nucleus and pyridinic dibasic acid(compound 1:evoninic acid, compound 2:wilfordic acid). The structure of compound $1[C_{47}H_{50}N_2O_{17},\;mp\;161{\sim}163^{circ}C$. $[{\alpha}]_D^{28}=+31.6^{\circ}$(c, 0.1 in EtOH)] was determined as novel structure named as euojaponine N, and compound $2[C_{48}H_{57}NO_{18},\;mp\;142{\sim}145^{circ}C,\;[{\alpha}_D^{27}=+27.0^{\circ}$(c, 0.1 in EtOH)] was identified as ebenifoline W-I reported from Maytenus ebenifolia.

• 공업화학
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• 제7권3호
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• pp.490-495
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• 1996

Organocyclosiloxane oligomer[$(R_2SiO)_n$, n=2, 3, 4, 5]와 dimethyldichlorosilane을 Pyridine N-oxide 촉매 존재하에서 개환 반응시켜 linear chlorine terminated siloxane(yields;71.2~86.5%)를 얻었다. $0^{\circ}C$에서 linear chlorine terminated siloxane과 dimethylamine을 반응시켜 amino terminated siloxane oligomer(yields;76.2~85.3%)를 얻은 후 이 화합물들과 1,4-bis(dimethylhydroxysilyl)benzene을 반응시켜 공중합체들(yields;58.0~71.0%)을 합성하였다. 이들 공중합체의 구조는 FT-IR 및 $^1H$-NMR로 확인하였으며, DSC 및 TGA thermogram을 통하여 이들 중합체들의 열적특성을 조사하였다. TGA thermogram으로부터 polymer I (n=2)의 초기분해온도는 $476^{\circ}C$로 가장 낮았고, polymer IV(n=5)가 $485^{\circ}C$로 가장 높았다. n의 수가 증가할수록 열안정성은 다소 우수한 것으로 관찰되었고, DSC thermogram에서 중합체들의 유리전이온도는 polymr IV (n=5)가 $-76^{\circ}C$로 가장 낮았으며, n의 수가 감소할수록 높게 나타났음을 알 수 있었다.

• Carbon letters
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• 제5권3호
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• pp.113-117
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• 2004

The mesophase pitch was prepared by adding 1~10 wt% of the borane-pyridine complex (BPC) to decant oil. It was prepared in a reactor held at $450^{\circ}C$ for 2 h in $N_2$ atmosphere. The mesophase pitches were analyzed using thermogravimetric analyzer (TGA), melting point apparatus, X-ray diffraction (XRD) and polarized optical microscope. The coke yield, softening point, toluene insoluble, density and content of anisotropy in the mesophase pitches were increased with BPC contents. The XRD profiles did not show any effect of addition of BPC on the formation of mesophase pitch, while the crystallinity of mesophase pitches was increased when the materials were heat treated with boron compound.

• Bulletin of the Korean Chemical Society
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• 제6권3호
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• pp.141-144
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• 1985

N-Arylation reaction of nitrogen-containing heterocycles such as pyridine, nicotinamide and 4,4'-bipyridine was studied. We prepared N-2,4-dinitrophenyl derivatives initially by reacting the above heterocycles with 2,4-dinitrochlorobenzene in ethanol, and then treated the N-2,4-dinitrophenylated heterocycles with various aniline derivatives, $XC_6H_4NH_2$(X = -H, p-$CH_3$, p-$C_2H_5$, p-Cl, p-CN, p-OH, p-$OCH_3$, o-Cl, m-$CH_3$) to yield the corresponding N-arylated compounds in fairly good yields. $H^1$-nmr patterns and peak assignments of the N-arylated products were described.