Synthesis of divinyl derivatives of 5-substituted l,2,4-triazole-3-thiones

Conclusions The reaction of 5-methyl-, 5-phenyl- and 5--furyl-l,2,4-triazole-3-thiones with acetylene gave their N 1, S- and N 2, S-divinyl derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1674–1676, July, 1986.     

Unusual Lability of Pentafluorophenoxy Group in Reactions of Potassium Aroxides with Pentafluoropyridine

The kinetics of the reactions of pentafluoropyridine with potassium aroxides, leading to formation of polyfluorinated aryl pyridyl ethers, conform to the Bro/nsted equation. The data obtained for potassium pentafluorophenoxide deviate from the general correlation because of readily occuring reverse reaction, replacement of the pentafluorophenoxy group by released fluoride ion. PM3 calculations of the electronic structure of the reagents, intermediate -complexes, and products showed that the replacement of fluorine in pentafluoropyridine is a charge-controlled process, whereas unusually easy replacement of the pentafluorophenoxy group in the corresponding aryl pyridyl ether by fluorine is explained by structural features of its lowest unoccupied molecular orbital.     

Investigation of 2,3'-Biquinolyl. 11. Regioselectivity in the Hydroxylation of 1-Alkyl-3-(2-quinolyl)quinolinium Halides

The hydroxylation of 1-alkyl-3-(2-quinolyl)quinolinium halides by an alkaline solution of K₃[Fe(CN)₆] in aqueous 1,4-dioxane leads to a mixture of 1-alkyl-3-(2-quinolyl)-1,2-dihydro-2-quinolones and 1-alkyl-3-(2-quinolyl)-1,4-dihydro-4-quinolones with predominance of the former. The use of the system of K₃[Fe(CN)₆]/Mg(OH)₂ in aqueous 1,4-dioxane leads to the regiospecific formation of 1-alkyl-3-(2-quinolyl)-1,4-dihydro-4-quinolones.     

Modification of unsaturated rubbers in low-temperature plasma as a method to improve their adhesion properties

The change in the contact-surface properties of the films of unsaturated rubbers under the effect of a direct-current discharge has been investigated in case of the placement of the samples at the anode. It has been demonstrated that the modification in plasma leads to a substantial improvement in the contact properties of rubber films.     

New Data on Astrophyllite Supergroup Minerals: Crystall Chemical Mechanisms of the Formation of Triclinic and Monoclinic Structures

Crystallography Reports - Crystall chemical mechanisms of the formation of triclinic and monoclinic species of astrophyllite supergroup minerals have been considered using the concept of mixed...