• Title/Summary/Keyword: cyano group

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Synthesis of 2-Cyanoimino-1,3-thiazoline (2-Cyanoimino-1,3-thiazoline 유도체의 합성)

  • Hahn, Hoh-Gyu;Nam, Kee-Dal;Park, Ik-Kyu;Mah, He-Duck
    • The Korean Journal of Pesticide Science
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    • v.7 no.2
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    • pp.155-158
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    • 2003
  • 2-Imino-1,3-thiazolines 1 show selective antifungal activity against pyricularia oryzae by new mode of action. A synthesis of novel 2-cyano-l,3-thiazolines 2 in which cyano moiety is substituted in imino group at C-2 of 1 is described. The lone pair electrons of sulfur and nitrogen as well as strong electron withdrawing cyano substituent in 1,3-thiazoline scaffold would effect the biological activity of 2-imino-1,3-thiazoline series. Regiospecific nucleophilic attack of thiourea 4 for $\gamma$-chloro-$\beta$-ketoacetoacetanilide 3 followed by acid catalyzed dehydration gave 2.

Impact of Cyano and Fluorine Group Functionalization on the Optoelectronic and Photovoltaic Properties of Donor-Acceptor-π-Acceptor Benzothiadiazole Derived Small Molecules: A DFT and TD-DFT Study

  • Prabhat Gautam;Anurag Gautam;Neeraj Kumar
    • Korean Journal of Materials Research
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    • v.33 no.6
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    • pp.236-241
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    • 2023
  • Solar cells based on p-conjugated donor-acceptor (D-A) organic molecular systems are a promising alternative to conventional electrical energy generation. D-A molecular systems, which have a triphenylamine (TPA) moiety linked with a benzothiadiazole (BTD) moiety, open the potential development of new small molecule donors for bulk heterojunction (BHJ) solar cells. Here, a series of donor-acceptor-π-acceptor (D-A-π-A) small molecule donors (SMD) derived from triphenylamine (TPA) donor and benzothiadiazole (BTD) acceptor building blocks, were designed for BHJ organic solar cells. The small molecule donors SMD1-4 were studied using density functional theory (DFT) and time dependent-DFT (TDDFT) methods, to understand the effect of cyano and fluorine group functionalization on their properties. The effect of structure alteration by cyano and fluorine group functionalization on the optoelectronic properties, the calculated highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) and the HOMO-LUMO gaps were theoretically explored. The Voc (open-circuit photovoltage) and fill factor (FF) for SMD1-4 were obtained with a PC71BM acceptor, which showed that these organic small molecules are potential small molecule donors for organic bulk heterojunction solar cells.

Photoluminescence Characteristics of p-Phenylene Vinylene and Its Derivatives in Solution and in Nanoaggregates

  • Eom, Intae;Lim, Seon Jeong;Park, Soo Young;Joo, Taiha
    • Rapid Communication in Photoscience
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    • v.4 no.3
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    • pp.70-72
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    • 2015
  • Oligomers of p-phenylene vinylene and its derivatives have drawn much attention due to their unusual emission characteristics of showing increased emission when they form into nanoparticles. We have investigated the optical properties of the oligo-(p-phenylene vinylene) and its cyano-substituted derivatives in solution and in nanoaggregate media by femtosecond and picosecond time resolved fluorescence as well as stationary spectroscopies. All the spectroscopic data are consistent with the conclusion that the cyano substitution on the ${\beta}$-position of oligo-(p-phenylene vinylene) leads to breakage of the otherwise planar structure of cyano-unsubstituted molecules, which opens up an extremely efficient, as fast as 100 fs, non-radiative relaxation channel of the excited state. Formation of the nanoaggregates reverts the effect to make the molecules planar and to block the non-radiative relaxation channel. Therefore, concerning the applications in organic electroluminescent devices and organic light emitting diodes, substitution by the cyano group is not advantageous, although such modification should be useful in respect of controlling fluorescence intensity in different media.

PHOTOISOMERIZATION STUDIES OF SUBSTITUTED DIPHENYLBUTADIENES: ROLE OF POLARIZED EXCITED STATES IN THE PHOTOPROCESSES OF $\alpha,\omega$-DIPHENYLPOLYENES

  • Singh, A.K.;Krishna, T.S.R.
    • Journal of Photoscience
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    • v.5 no.2
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    • pp.47-51
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    • 1998
  • Direct irradiation of 1Z,3E-1-cyano-1,4-diphenylbutadiene (2) and 1Z,3E-1-cyano-3-methyl-1,4-diphenylbutadiene (3) in organic solvents viz. n-hexane, methanol and acetonitrile results in preferential isomerization of the double bond substituted with cyano group via one-photon-one-bond isomerization process. The quantum efficiency of the isomerization of 3 is more than 2 in all the three solvents. Photoproducts of 2 and 3 (viz. 2a, 2b, 3a, 3b) also exhibited similar photoisomerization trends. The results are discussed in terms of the effects of substituents on the potential energy surface of the excited singlet states of $\alpha$,$\omega$-diphenylpolyenes, and the role of zwitterionic dipolar species in the photoisomerization process of linearly conjugated C=C polyenes is highlighted.

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Rhodium-Catalyzed Reductive Decyanation of Nitriles Using Hydrosilane as a Reducing Agent: Scope, Mechanism and Synthetic Application

  • Tobisu, Mamoru;Nakamura, Ryo;Kita, Yusuke;Chatani, Naoto
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.582-587
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    • 2010
  • A rhodium-catalyzed reductive cleavage reaction of carbon-cyano bonds is developed using hydrosilane as a mild reducing agent. A wide range of nitriles, including aryl, benzyl, and $\beta$-hydrogen containing alkyl cyanides are applicable to this decyanation reaction. The method is also applicable to organic synthesis, in which benzyl cyanide is used as a benzyl anion equivalent and a cyano group functions as a removable ortho-directing group.

Synthesis and Exploratory Photochemistry of ${\beta},\;{\gamma}$-unsaturated Carboxylic Acid, Carboxamide and Nitrile Derivatives (${\beta},\;{\gamma}$-불포화카르복시산, 카르복시아미드와 니트릴 유도체의 합성과 이들의 광화학적 반응에 관한 연구)

  • Givens Richard S.;Woo Ki Chae
    • Journal of the Korean Chemical Society
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    • v.26 no.2
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    • pp.99-106
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    • 1982
  • The ketone chromophore of 1-Acetyl-1-methyl-2-cyclopentene (1) was replaced by nitrile, carboxylic acid and acetamide group, and their photochemical reactions were investigated. While the ${\beta},\;{\gamma}$-unsaturated ketone 1 afforded 1,2 ar 1,3-Acyl shift product, these replaced chromophores did not afford any monomeric rearranged products. 1-Cyano-1-methyl-2-cyclohexene also afforded no product anology of the 1,2-acyl shift reaction. The replacement of the ketone chromophore by nitrile, carboxylic acid and carboxamide has greatly altered the photochemistry of ${\beta},\;{\gamma}$-unsaturated ketones.

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Chemical Structure Analysis of Non-ionic Monomer Contrast Agents Using 1H-NMR Spectroscopy (1H-NMR Spectroscopy를 이용한 Non-ionic Monomer 조영제의 화학적 구조 분석)

  • Han, Beom-Hee
    • Journal of radiological science and technology
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    • v.44 no.4
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    • pp.335-342
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    • 2021
  • Studies on the side effects of contrast agents are being discussed based on various cases, but studies analyzing the chemical structure of the underlying contrast agents are difficult to understand as the manufacturers have not disclosed them. Therefore, in this study, the chemical structure of the contrast medium was analyzed using 1H-NMR spectrometer for Omnipaque contrast medium prepared from Iohexol, which is a nonionic iodide contrast medium, Xenetix contrast medium from Iobitridol, and Iomeron contrast medium from Iomeprol. As a result, it was found that the Omnipaque contrast medium of Iohexol had 6 carboxyl groups, 3 carbonyl groups, 4 amine groups, 1 methyl group, and 2 cyano groups. It was found that the Xenetix contrast medium of the iobitridol formulation had 6 carboxyl groups, 3 carbonyl groups, 2 amine groups, and 4 cyano groups. It was found that the Iomeron contrast agent of the Iomeprol formulation had 5 carboxyl groups, 3 carbonyl groups, 4 amine groups, 1 methyl group, and 2 cyano groups. As shown in this study, the chemical structure of the non-ionic monomer contrast agent increases its affinity with water by binding a number of hydroxyl groups (OH) to the carboxyl group. It is necessary to accurately identify each of these factors and analyze the physical and chemical changes of the contrast medium according to various environmental factors.

Synthesis and Light-Emitting Properties of Poly(phenylene ethynylene) derivative Containing Cyano substituent

  • Chi, Jun-Ho;Lee, Chang-Lyoul;Kim, Jang-Joo;Jung, Jin-Chul
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.595-598
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    • 2004
  • A novel poly(phenylene ethynylene) derivative containing cyano group as electron-transporting moiety was synthesized via Pd-catalyzed coupling reaction. The structures of the monomers and polymer were confirmed by spectroscopy. The polymer demonstrated a wide variation of solubility, optical absorption, electrical conductivity and electrochemical properties.

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