• Title/Summary/Keyword: Radical chemistry

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Radical Ring-Crossover Polymerization of Macrocycles with Radically Exchangeable Dynamic Covalent Bonds

  • Otsuka, Hideyuki;Yamaguchi, Go;Takahara, Atsushi
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.320-320
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    • 2006
  • The authors report the synthesis and radical ring-crossover polymerization of macrocycles with radically exchangeable dynamic covalent bonds. The macrocyclic compounds with alkoxyamine units were designed and synthesized by condensation from alkoxyamine-based diol and the corresponding acid chlorides in the presence of pyridine under high-dilution condition. The macrocycles can thermally polymerize by intermolecular radical crossover reaction. Furthermore, the poly(alkoxyamine)s depolymerized to the monomers principally by the intramolecular radical exchange process under high-dilution conditions.

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The Double Photodissociation of Geminal, Dichloride

  • Platz, M. S.;Lee, Woo-Bung
    • Bulletin of the Korean Chemical Society
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    • v.10 no.4
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    • pp.374-377
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    • 1989
  • Photolysis of dichlorodiphenylmethane in glassy 2-MeTHF at 77K results in the formation of diphenylcarbene and the diphenylchloromethyl radical, which were detected by their flourescence emission and excitation spectra. The relative yield of the carbene to radical is shown to vary dramatically as a function of irradiation time. The photolability of the radical is also demonstated. These results were interpreted in terms of a two step mechanism, where the diphenylchloromethyl radical is an intermediate in the formation of diphenylcarbene.

Theoretical Study of the Reaction Mechanism for SiF2 Radical with HNCO

  • Hou, Li-Jie;Wu, Bo-Wan;Kong, Chao;Han, Yan-Xia;Chen, Dong-Ping;Gao, Li-Guo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3738-3742
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    • 2013
  • The reaction mechanism of $SiF_2$ radical with HNCO has been investigated by the B3LYP method of density functional theory(DFT), while the geometries and harmonic vibration frequencies of reactants, intermediates, transition states and products have been calculated at the B3LYP/$6-311++G^{**}$ level. To obtain more precise energy result, stationary point energies were calculated at the CCSD(T)/$6-311++G^{**}$//B3LYP/$6-311++G^{**}$ level. $SiF_2+HNCO{\rightarrow}IM3{\rightarrow}TS5{\rightarrow}IM4{\rightarrow}TS6{\rightarrow}OSiF_2CNH(P3)$ was the main channel with low potential energy, $OSiF_2CNH$ was the main product. The analyses for the combining interaction between $SiF_2$ radical and HNCO with the atom-in-molecules theory (AIM) have been performed.