• 한국인쇄학회지
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• 제13권2호
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• pp.33-45
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• 1995

1, 4-Diketo-3, 6-diphenyl-pyrrolo-[3, 4c]-pyrrole(abbriviated DPP) is a new heterocyclic pigment of red color whose chlorinated derivative is now on the market. DDP was synthesized from benzonitrile and diethylsuccinate. Pariser-parr-pople(PPP) molecular orbital calculations have been carried out on the DPP in other to study spectroscopically the DPP chromophore on deprotonation.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4447-4449
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• 2011

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.100-103
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• 2003

The basic structure of porphyrin consists of four pyrrole units linked by four methine bridges. It reveals that the cyclic 16-atom is the preferred cyclic system for n-electron delocalization since this pathway exhibits the highest degree of bond equalization. Scheme 1 (a) shows the 16-center system is the chromogen of the porphyrins, which allows 18-electron delocalization that could produce aromatic characteristics (1,2). (omitted)

• 대한화학회지
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• 제60권1호
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• pp.21-27
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• 2016

Novel push-pull chromophores containing 5’-(4-(bis(9,9-dimethyl-9H-fluoren-2-yl)aniline (bisDMFA) as a donor and phenylazo-methylpyrrolyl-boron difluoride (PhAPy-BF₂) as an acceptor were designed and synthesized by the Knoevenagel condensation reaction for organic solar cells. Various electron withdrawing moieties were effectively introduced using 2,4-dimethyl-1H-pyrrole to afford new asymmetric BF₂-azopyrrole molecules that were characterized by UV-vis spectroscopy and cyclic voltammetry measurements.

• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1281-1285
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• 2005

• Bulletin of the Korean Chemical Society
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• 제21권1호
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• pp.97-100
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• 2000

Acid-catalyzed porphyrin formation from meso-aryltripyrromethanes and $25-bis({\alpha}$, - hydroxyl - $\alpha$ -phenyl) methylfuran is studied. The condensation resulted in selective scrambling of tripyrromethanes when the condensation was carried out with catalytic amounts of $BF_3$ in methylene chloride. But the reaction carried out with p-TsOH or $BEt_3$ catalysts in the presence of $NH_4Cl$ in acetonitrile, single porphyrin product was isolated without scrambling of starting tripyrromethane. The yields of porphyrin in these studies were somewhat lower than those of 2+2 condensations or aldehyde-pyrrole condensations.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.929-934
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• 1999

2-( β-Alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles (14) were synthesized from 4-acylpyrrole-2-carboxylates (8) by sequential reduction of their acyl and alkoxycarbonyl groups to give 4-(1-hydroxyalkyl)pyrrole-2-carbalde-hydes (13) followed by Wittig reaction of the aldehydes with the ylide of alkoxymethylphosphonium chloride. Diels-Alder reaction of 2-(β-alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles with trans-methyl β-nitroacrylate gave 6-alkoxy-3-(1-hydroxyalkyl)-5-nitro-4,5,6,7-tetrahydroindole-4-carboxylates (3).

• Bulletin of the Korean Chemical Society
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• 제21권6호
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• pp.618-622
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• 2000

The '3+1'type condensation of 16-thiatripyrromethane with $N-alkyl-24-bis[(\alpha+hydroxy-\alpha-phenyl)methyl]pvrole$, in the presence of acid catalyst afforded core-modified, N-confused porphyrins bearing alkyl groups at the rim nitrogen. The proton NMR spectra indicate that the bulkiness of the N-alkyl substituents is somewhat relatedwith the tiltedness of the inverted pyrrole ring. The changes in chemical shift of inner methine protons depending on the N-alkyl group and protonation site is discussed.

• 한국연초학회지
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• 제27권1호
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• pp.127-133
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• 2005

This study was conducted to determine the aroma and volatile component changes from a different stalk positions of Korean flue-cured tobacco. Eight different stalk positions of flue-cured leaf tobaccos harvested in 2001 were used for this study. Thermal extraction method at two different treatment temperature($50\;amp;\;80^{\circ}C$) was applied for this experiment. Forty eight kinds of aroma and volatile components such as 2,4-heptadienal, hexadecane, 1-methyl-1H- pyridine, 2,5-dimethyl-1H-pyrrole were analyzed by using thermal extraction method. All of aroma and volatile components of leaf tobaccos were changed from a different stalk positions and treatment temperature. Leaf tobaccos in middle stalk position have a higher concentration of aroma and volatile components such as norsolanidione, 4-pyridinecarboxaldehyde, 4-methyl-4-OH-2-pentanone, acetic acid, propylene glycol, 1-methyl-2-pyrrolidinone, 2,5-dimethyl-1H-pyrrole. Also, Megastigmatrienone 1, 3-oxo-[alpha]­ionol, 6,10,14-trimethyl-2-pentadecanone, heptadecane, 6-methyl-2-isohexyl-l-heptene concentration were low in the middle stalk position and high in both bottom and upper position. Treatment temperature affected on the changes of many aroma and volatile components in leaf tobacco. Most of aroma and volatile components such as, 2,4-Heptadienal, dodecanoic methylester, famesol isomer and 3-acetylpyridine were sharply increased as increasing treatment temperature. This results can be used to estimate the aroma characteristics of cigarette blend using a different stalk position of leaf tobacco.

• 전기화학회지
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• 제5권1호
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• pp.13-16
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• 2002

Fullerene으로 수식된 PPy(Polypyrrole)전극 즉, graphite(Gr)/ppy, fullerene $(full^-)$항을 Gr/5mM PPy, 1mM $full^-,0.1M\;TBABF_4,\; CH_3CN/Pt$형의 전지로 전기화학 중합법으로 제작하였다. $(full^-)$의 생성속도는 기질전극 재료인 Pt/ppy, Pt, Gr 및 Au전극에 대해 각각 93.6, $7.0\times10^2,\;42.6$ 및 $1.3\times10^2cms^{-1}$였다. 수식되지 않은 Gr/ppy와 수식된 $Gr/ppy, full^-$ 전극에 대한 어드미턴스 값이 $1.7\times10^{-3}S$에서 $8.3\times10^{-3}S$로 5배나 증가하였으며, 전기 이중층의 용량은 $2.4\times10^{-5}\;F$에서 $4.2\times10^{-5}\;F$로 174배 증가하였다.