• Title/Summary/Keyword: Pyrrole

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Theoretical Analysis on Molecular Magnetic Properties of N-Confused Porphyrins and Its Derivatives

  • Wei, Wei;Bai, Fu-Quan;Xia, Bao-Hui;Zhang, Hong-Xing
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2937-2942
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    • 2012

  • We have theoretically investigated the magnetic properties of N-confused porphyrin (NCP), tetraphenyl-N-confused porphyrin (TPNCP) and their substituted derivatives with O, S and Se heteroatoms (2ONCP, 2STPNCP, 2SeNCP, 2OTPNCP, etc.) by using DFT method. In the minimum energy structures of the 2OTPNCP, the two couples opposite phenyl substitutes are staggered. In the case of TPNCP, 2STPNCP and 2SeTPNCP, two phenyls being respectively close to or opposite to N-confused pyrrole are found to be pointed the same direction, whilst others are in the opposite direction. Based on the equilibrium structures, the $^1H$ chemical shifts and nucleus-independent chemical shifts (NICS) are calculated in this paper. The ${\pi}$ current density being induced by the tridimensional perpendicular magnetic field transmits the inner section of the pyrrole segments for NCP and TPNCP. As for their substituted derivatives with O, S and Se atoms, the current path passes through the outer section of the two heterorings. The NICS values at the ring critical points of the heterorings are much lower (in absolute value) than those of which is at the center of an isolated pyrrole molecule. The $^1H$ NMR for ${\beta}H$ atoms of the heterorings decreases from O, S to with Se.

  • https://doi.org/10.5012/bkcs.2012.33.9.2937 인용 PDF KSCI

Electrochemical Synthesis of Conducting Polypyrrole in Nucleophilic Solvent (친핵성 용매하에서 전도성 Polypyrrole의 전기화학적 합성)

  • Lee, Hong-Ki;Park, Soo-Gil;Shim, Mi-Ja;Kim, Sang-Wook;Lee, Ju-Seong
    • Applied Chemistry for Engineering
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    • v.5 no.4
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    • pp.616-623
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    • 1994

  • Conductive Polypyrrole films have been synthesized by electrochemical method in nucleophilic solvent such as N, N-dimetylformamide(DMF), dimethylsulfoxide(DMSO). The effect of protic acid as supporting electrolyte to decrease the nucleophilicity of the solvent was studied. Cyclic voltammetry, I-t transients were carried out to investigate the electrodeposition of conductive polypyrrole film on platinum electrode. Three peaks of 0.65V, 0.85V, and 1.2V vs. $Ag/AgNO_3$ indicated oxidation of monomer, oxidation of pyrrole to the platinum electrode and decomposition of polypyrrole film, respectively. With the I-t transients, nucleation process was confirmed and from obtained linear fits of I vs.t2resembles the metal film formation, and 2.15-2.26 of n-value could be calculated. As concentration of pyrrole or prolic acid was increased, the conductivity of polypyrrole film increased linearly. Tensile strength and elongation were investigated for comparing the mechanical properties and also SEM was performed for morphology investigation.

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