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Electrochromic Properties of Symmetric and Asymmetric Viologens (대칭, 비대칭 Viologen 유도체의 전기변색특성)

  • Kim, Sung Hoon;Bae, Jin Seok;Hwang, Seok Hwan;Gwon, Tae Sun;Do, Myung Ki;Park, Chul
    • Journal of the Korean Chemical Society
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    • v.40 no.11
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    • pp.686-691
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    • 1996
  • Several kind of viologen derivatives were synthesized and the electrochromic property of these compounds was examined by cyclovoltametric and chronoamperometric method, relating to the mechanisum of coloring reaction. The electrochromic properties of 1,1'-diethyl-4,4'-bipyridinium dibromide(EV), 1,1'-dipropyl-4,4'-bipyridinium dibromide(PV), 1,1'-dibuthyl-4,4'-bipyridinium dibromide(BV) and 1-ethyl-1'-butyl-4,4'-bipyridinium dibromide(EBV) are studied by using an propylenecarbonate/methanol solution with $Bu_4NBF_4$ as supporting electrolyte. A monomer-dimer equilibrium was proposed to explain the related observation that EV and EBV cation radical solutions are violet at an applied voltage of 1.7∼3.0V but become blue in open-circuit condition.

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Synthesis of -4,9-Dione Derivatives (벤조-[f]-인돌-4, 9-디온 유도체의 합성)

  • Lee, Ji-Young;Suh, Myung-Eun
    • YAKHAK HOEJI
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    • v.34 no.1
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    • pp.15-21
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    • 1990
  • -4,9-dione derivatives were prepared from $2-chloro-3-({\alpha}-accetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ and 2-chloro-3-N-phenylamino-1,4-naphthoquinone. $2-Chloro-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ was reacted with amines to give $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ derivatives. Subsequent treatment of $2-amino-3-({\alpha}-acetyl-{\alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ with sodium ethoxide gave -4,9-dione derivatives. When 2-chloro-3-N-phenylamino-1,4-naphthoquinone reacted with sodium ${\alpha}-cyano$ ethyl acetate, 2-amino-3-ethoxycarbonyl-N-phenyl--4,9-dione was obtained. However, with sodium diethyl malonate, not -4,9-dione but 2-chloro-3-bis-(methoxycarbonyl)-methyl-2H-3-N-phenylamino-1,4-naphthoquinone was obtained.

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A Study of Intercalations-complex of Montmorillonite as Model-system (III) (Model-system으로서의 몬트모릴로나이트의 층간화합물에 관한 연구 (III))

  • 조성준
    • Journal of the Korean Ceramic Society
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    • v.38 no.5
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    • pp.431-437
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    • 2001
  • 본 연구에서는 양이온 교환반응에 의해 Na-Mont와 R$_{11}$SO$_4$로부터 R$_{11}$SO$_4$-Mont 층간화합물을 합성한 후, 이 R$_{11}$SO$_4$-Mont 층간화합물을 다시 제 4차 유기 양이온인 (Et)$_4$N$^{+}$ 이온 및 (Bu)$_4$N$^{+}$ 이온과 반응시켜 그 거동을 살펴보았다. R$_{11}$SO$_4$-Mont를 (Et)$_4$N$^{+}$이온과 반응시켰을 대보다 (Bu)$_4$N$^{+}$ 이온과 반응시킨 경우에 좀 더 큰 층간거리가 얻어졌다. R$_{11}$SO$_4$-Mont를 (Et)$_4$N$^{+}$이온 및 (Bu)$_4$N$^{+}$과 반응시켜 얻은 층간화합물을 다시 아세토니트릴, 에탄올 및 디옥산과 팽윤반응을 수행한 결과 층간거리가 확장되었으나, 이는 Na-Mont를 R$_{11}$SO$_4$와 48시간 교환 반응시킨 후에 교환용액 하에서 얻은 R$_{11}$SO$_4$-Mont의 층간거리에 불과했다. 원소분석결과, R$_{11}$SO$_4$-Mont와 (Bu)$_4$N$^{+}$를 반응시킬 경우 반응이 반응식 b에 의거 진행되고, (Bu)$_4$N-Mont를 R$_{11}$SO$_4$와 반응시킬 경우에는 반응식 c에 의거 진행됨을 예측할 수 있었다.의거 진행됨을 예측할 수 있었다.

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Synthesis of New Crown Ethers Containing Benzothiazole Group (벤조티아졸기를 갖는 새로운 크라운 에테르의 합성)

  • Chang, Seung-Hyun;Yeon, Ae-Sook;Chung, Kwang-Bo
    • Journal of the Korean Chemical Society
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    • v.40 no.2
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    • pp.117-121
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    • 1996
  • Two new crown ethers containing nitrogen and sulfur atoms adjacent to the crown rings were prepared. 4'-Benzothiazolylbenzo-12-crown-4 (1) or 4'-benzothiazolylbenzo-15-crown-5 (2) were synthesized by reaction of 2-aminothiophenol with 4'-formylbenzo-12-crown-4 (3) or 4'-formylbenzo-15-crown-5 (4) respectively. (3) and (4) were obtained by reaction of 3, 4-dihydroxybenzaldehyde with tri- or tetraethyleneglycol ditosylate. Triethyleneglycol ditosylate or tetraethyleneglycol ditosylate were synthesized by reaction of p-toluenesulfonylchloride with triethyleneglycol or tetraethyleneglycol in the presence of sodium hydroxide.

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Synthesis and Antifungal Evaluation of 6-(N-arylamino)-7-methylthio-5,8-quinolinediones

  • Kim, Chung-Kyu;Choi, Jung-Ah;Kim, Sung-Hee
    • Archives of Pharmacal Research
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    • v.21 no.4
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    • pp.440-444
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    • 1998
  • A series of 6-(N-arylamino)-7-methylthio-5,8-quinolinedione derivatives 4a-4l was newly synthesized for the evaluation of antifungal activity. 6-(N-Arylamino)-7-methylthio-5,8-quinolinediones were prepared by regioselective nucleophilic substitution of 6,7-dichloro-5,8-quinolinediones with arylamines in the presence of $Ce^{3+}$, and $Na_2$S/dimethylsulfate. The MIC values of 4a-4l were determined for antifungal susceptibility in vitro against Candida species by agar streak method. The derivatives 4a-4l had generally potent antifungal activities against all human pathogenic fungi. Especially they had the most potent activity against C. krusei at 12.5-0.8 $\mu\textrm{g}$/ml. Compounds 4d, 4g, 4h, 4j and 4k had more potent antifungal activities than fluconazole. Compounds 4g and 4h completely inhibited the fungal growth at 0.8-6.3 $\mu\textrm{g}$/ml against all Candida species, while fluconazole inhibited the growth at 25 $\mu\textrm{g}$/ml. The compounds such as 4g and 4h containing an N-(4-bromo-2-methylphenyl)- or N-(4-bromo-3methylphenyl)amino substituent exhibited the most potent antifungal activities.

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Dialkylaminomethylation of 1,4-Dihydropyridine (1,4-Dihydropyridine의 Dialkylaminomethyl화 유도체의 합성)

  • Suh, Jung-Jin;Hong, You-Hwa
    • YAKHAK HOEJI
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    • v.33 no.5
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    • pp.280-284
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    • 1989
  • When 2,6-Dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-mono methyl ester(3) was reacted with dimethyl methylene ammonium chloride (5a) and $K_2CO_3$ in DMF, 2,6-dimethyl-4-(3'-nitrophenyl)-5-(N,N-dimethylamino)methyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (6a) was obtained in 41% yield. As the same procedure with compound (3) and the other dialkylaminomethylating reagents (5b, c, d, e), 2,6-dimethyl-4-(3'-nitrophenyl)-5-(N,N-diethylamino)methyl-1,4-dihydropyridine-3-carboxylic acid methylester(6b), 2,6-dimethyl-4-(3'-nitrophenyl)-5-(1'-pyrrolidinyl)methyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (6c), 2,6-dimethyl-4-(3'-nitrophenyl)-5-(1'-piperidinyl)methyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (6d) and 2,6-dimethyl-4-(3'-nitrophenyl)-5-(1'-morpholinyl)methyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (6e) were obtained in 28%, 49%, 48% and 18% yield respectively.

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The Reaction of the Tripledecker Complexes, 4(CpCo)_2(C_4R_4)$ and Alkynes (Tripledecker 착물, $(CpCo)_2(C_4R_4)$과 Alkyne과의 반응)

  • Uhm, Jae-Kook;Lee, Won-Sik;Kim, Seog-Bong;Cha, Jin-Soon;Lee, Hyung-Soo;Lee, Dong-Ho;Kim, Hong-Seok;Sim, Sang-Chul
    • Journal of the Korean Chemical Society
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    • v.37 no.9
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    • pp.832-836
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    • 1993
  • The tripledecker complexes, bis-(${\eta}^5-cyclopentadienyl)-{\mu}-({\eta}^4-1,2,3,4-tetraalkylcyclobutadiene$)dicobalt were produced by the reaction of Jonas reagent with 2-hexyne and 3-hexyne in the maximum yield (above 50%) when they were reacted in eq-molar amounts at room temperature. A tripledecker complex, bis-${\eta}^5-cyclopentadienyl)-{\mu}-({\eta}^4-1,2,3,4-tetraethyl cyclobutadiene$)dicobalt(13) was isomerized to (${\eta}^5-cyclopentadienyl)cobaltacyclopentadiene-{\mu}-({\eta}^4-2,4-cobaltacyclopentadiene$)(${\eta}^5-cyclopentadienyl$)cobalt(15) on reacting with 3-hexyne at room temperature. Another tripledecker complex, bis-(${\eta}^5-cyclopentadienyl)-{\mu}-({\eta}^4-1,3-dimethyl-2,4-dipropyl cyclobutadiene$)dicobalt(14) was decomposed to give 1,3,5-trimethyl-2,4,6-tripropylbenzene through an intermediate complex by the reaction of 2-hexyne.

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Padded jacket patterns according to padding thickness for women in their 20s (패딩 두께에 따른 20대 여성용 패딩 재킷 패턴)

  • Lee, Hea-Seung;Suh, Mi-A;Uh, Mi-Kyung
    • The Research Journal of the Costume Culture
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    • v.21 no.5
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    • pp.755-764
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    • 2013
  • This study intends to use the basic patterns in 3oz bodice and 2oz sleeve padded jackets made for women in their 20s to research the proper ease of 2oz bodice and 2oz sleeve, 4oz bodice and 3oz sleeve padded jackets. The study also proposes a method of designing padded jacket patterns according to padding thickness. The results of this study are as follows: The 2oz bodice and 2oz sleeve padded jackets had the following sizes. The front and back bust, waist, and hip circumferences were calculated as B/4+2.5cm and B/4+3cm, W/4+2.6+3.3(D)cm and W/4+1.5+2.6(D)cm, and H/4+2.8cm and H/4+3cm, respectively. The length of the jacket was 62.4cm, and the sleeve length was calculated as 63.4cm. For the 4oz bodice and 3oz sleeve padded jackets, the front and back bust, waist, and hip circumferences were calculated as B/4+4cm and B/4+4cm, W/4+4.1+3(D)cm and W/4+2.5+3.6(D)cm, and H/4+4.3cm and H/4+4cm, respectively. The length of the jacket was 63.2cm, and the sleeve length was calculated as 64.2cm. The results of this study showed that padded jackets with thicker padding need more ease. For jackets with stitches, the decreased lengths must be added in the pattern length. The 2oz bodice and 2oz sleeve, 4oz bodice and 3oz sleeve padded jackets all scored 4 points or higher in the movement functionality assessment, thus showing outstanding movement functionality.

The Usefulness of 4D Echocardiographic Modality for Assessing RV Affection in Uncontrolled Hypertensive Patients

  • Rehab M. Hamdy;Shaimaa A Habib;Layla A Mohamed;Ola H. Abd Elaziz
    • Journal of Cardiovascular Imaging
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    • v.30 no.4
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    • pp.279-289
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    • 2022
  • BACKGROUND: In many cardiovascular disorders, the contractile performance of the right ventricle (RV) is the primary determinant of prognosis. For evaluating RV volumes and function, 4 dimensional (4D)-echocardiography has become common. This research used 2D and 4D modalities to assess RV contractile performance in hypertensive patients. METHODS: A total of 150 patients with essential hypertension were enrolled in this study, along with 75 age and sex-matched volunteers. Clinical evaluation and echocardiographic examination (including M-mode, tissue Doppler imaging, and 2D speckle tracking) were conducted on all participants. RV volumes, 4D-ejection fraction (EF), 4D-fractional area change (FAC), 4D-tricuspid annular plane systolic excursion (TAPSE), 4D-septal and free wall (FW) strain were all measured using 4D-echocardiography. RESULTS: Hypertensive patients showed 2D-RV systolic and diastolic dysfunction (including TAPSE, 2D-right ventricular global longitudinal strain, RV-myocardial performance index and average E/EaRV) and 4D-RV impairment (including right ventricular EF, FAC, RV strain and TAPSE, right ventricular end-diastolic volume and right ventricular end-systolic volume) compared to the control group. We verified the prevalence of RV systolic dysfunction in hypertension patients using the following parameters: 1) 15% of them had 2D-TAPSE < 17 mm vs. 40% by 4D-TAPSE; 2) 25% of them had 2D-GLS < 19% vs. 42% by 4D-septal strain and 35% by 4D FW strain; 3) 35% of hypertensive patients had 4D-EF < 45%; and finally; 4) 25% of hypertensive patients had 2D-FAC < 35% compared to 45% by 4D-FAC. CONCLUSIONS: The incidence of RV involvement was greater in 4D than in 2D-modality trans-thoracic echocardiography. We speculated that 4D-echocardiography with 4D-strain imaging would be more beneficial for examining RV morphology and function in hypertensive patients than 2D-echocardiography, since 4D-echocardiography could estimate RV volumes and function without making geometric assumptions.

Shape-Selective Catalysis over Zeolite. An Attempt in the Alkylation of Biphenyl

  • Sugi, Yoshihiro;Komura, Kenichi;Kim, Jong Ho
    • Applied Chemistry for Engineering
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    • v.17 no.3
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    • pp.235-242
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    • 2006
  • Liquid phase alkylation of biphenyl (BP) was studied over large pore zeolites. Selective formation of the least bulky products, 4,4'-diisopropylbiphenyl (4,4'-DIPB) occurred only in the isopropylation of BP over some large pore molecular sieves. H-mordenites (MOR) gave the highest selectivity among them. The dealumination of MOR enhanced catalytic activity and the selectivity of 4,4'-DIPB because of the decrease of coke-deposition. Non-selective catalysis occurs on external acid sites over MOR with the low $SiO_2/Al_2O_3$ ratio because severe coke-deposition deactivates the acid sites inside the pores by blocking pore openings. The selectivity of DIPB isomers was changed with reaction temperature. Selective formation of 4,4'-DIPB was observed at moderate temperatures such as $250^{\circ}C$, whereas the decrease of the selectivity of 4,4'-DIPB occurred at higher temperatures as $300^{\circ}C$. However, 4,4'-DIPB was almost exclusive isomer in the encapsulated DIPB isomers inside the pores even at high temperatures. These decreases of the selectivity of 4,4'-DIPB are due to the isomerization of 4,4'-DIPB on the external acid sites. Some 12-membered molecular sieves, such as SSZ-24, MAPO-5 (M:Mg, Zn, Si), SSZ-31, and ZSM-12, which have straight channels, gave 4,4'-DIPB with moderate to high selectivity; however; SSZ-55, SSZ-42, and MAPO-36 (M: Mg, Zn) gave lower selectivity because of cages in 12-membered one dimensional channels. Three dimensional H-Y and Beta zeolites also yield 4,4'-DIPB in low yield because of their wide circumstances for the isopropylation of BP. The increasing the size of alkylating agent enhanced the shape-selective alkylaiton even for the zeolites, such as UTD-1. The ethylation of BP to ethylbiphenyls (EBPs) and diethylbiphenyls (DEBPs) over MOR was non-selective. The ethylation of BP to EBPs was controlled kinetically. However, there was difference in reactivity of EBPs and DEBPs for their further ethylation. 4-EBP was ethylated preferentially among the isomers, although the formation of 4,4'-DEBP was less selective. The least bulky 4-EBP and 4,4'-DEBP have the highest reactivity among EBPs and DEBPs for the ethylation to polyethylbiphenyls (PEBPs). These results show that the environments of MOR pores are too loose for shape selective formation of the least bulky isomers, 4-EBP and 4,4'-DEBP in the ethylation of BP, and that MOR pores have enough space for the further ethylation of 4,4'-DEBP.