Polarographic reduction of 1-substituted 1,2,4-triazoles

The polarographic reduction of 1-substituted 1,2,4-triazoles in dimethylformamide (DMF) and acetonitrile was studied. 1-Methyl-, 1-ethyl-, and 1,2,4-triazoles are not reduced on a mercury electrode over the range of potentials accessible for polarography. 1-Phenyl-1,2,4-triazole and 1-vinyl-1,2,4-triazole are reduced in acetonitrile via a one-electron mechanism at high negative potentials. The reduction of 1-vinyl-1,2,4-triazole is accompanied by polymerization of the electrolysis products. A possible mechanism for the electrochemical reduction is discussed. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 408–410, March, 1980.     

Novel conversion of 6H-1,3,5-oxathiazine S-oxides into 5-membered heterocyclic compounds

5H-1,2,4-oxathiazoles were efficiently synthesized from 6H-1,3,5-oxathiazine S-oxides by thermal cycloreversion of the substrates and the products were effectively converted into 1,2,4-thiadiazoles. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:175–186, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20004     

Novel conversion of 6H-1,3,5-oxathiazine S-oxides into 3H-1,2,4-dithiazoles by treating with Lawesson's reagent

Treatment of 6H-1,3,5-oxathiazine S-oxides by Lawesson's reagent (LR) at high temperature furnished 3H-1,2,4-dithiazoles in moderate to good yields. Deoxygenation of 6H-1,3,5-oxathiazine S-oxides was performed by LR in the presence of EtOH. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:208–215, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20011     

Polarized light-induced anisotropy depending on polymer matrices studied by polarized ftir spectroscopy

Polarized-light induced anisotropy of Disperse Orange 3 (DO3) depending on the polymer matrices was investigated by polarized FTIR spectroscopy. The dynamic behavior of the azo dyes doped in a series of methacrylate polymers was analyzed in terms of the orientation factors. Two factors, the free volume and the local polarity of matrices, are found to govern the dynamic behavior of DO3. It was found that induced anisotropy for trans and cis isomers varies depending on Tg of polymer matrix. Further, the thermal isomerization rate depend on the isomerization mode which is governed by the matrix polarity. The branched-alkyl chains are considered to block the interaction between ester groups and DO3 and introduce the DO3 molecules into the less polar environment.