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Stretched all-trans conformations were found preferable in computed structures of bis-imidazolium dications with short aliphatic (С1–С4) and hydroxyl substituted –СН2–СНОН–СН2– bridges. The molecular electrostatic potential is distributed unevenly in the dications: maxima of molecular electrostatic potential are located near С2Н imidazolium and bridge hydrogens for the α,ω-alkenyl bridges, and close to hydroxyl hydrogen for the hydroxypropane bridge. Intramolecular hydrogen bonds С–Н···ОН contribute to a significantly higher rotational barrier around С1–C2 bond in dications with a hydroxypropane bridge compared with polymethylene bridges. [ABSTRACT FROM AUTHOR]

A number of α,ω-bis(2-acetylphenoxy)alkanes have been synthesized with a yield of 40–90% by alkylation of 2′-hydroxyacetophenone with α,ω-dihaloalkanes. The X-ray data had allowed to reveal an effect of the size of the polymethylene linker on the conformations of α,ω-bis(2-acetylphenoxy)alkanes, which affect the melting points and are manifested in the UV spectra. A hypothesis that the conformation of α,ω-bis(2-acetylphenoxy)alkanes is determined by noncovalent interactions has been made on the basis of quantum-chemical calculations. Evaluation of the selectivity of the reaction of α,ω-bis(2-acetylphenoxy)alkanes with the entire series of alkali metal ions has demonstrated that a increase in the size of the polymethylene linker along the homologous series leads to an increase in the selectivity of the reaction with sodium ions, when the linker contains an odd number of methylene groups and with sodium and potassium ions, when the linker contains an even number of methylene groups. [ABSTRACT FROM AUTHOR]

The reactions of allyl ethyl, allyl butyl, allyl glycidyl, allyl benzyl, and allyl phenyl ethers with 1,1,3,3-tetra-methyldisiloxane in the presence of platinum(II) immobilized on polymethylene sulfide have been studied. [ABSTRACT FROM AUTHOR]

Hydrosilylation of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane with 1,1,3,3-tetramethyldisiloxane in the presence of platinum(II) immobilized on polymethylene sulfide is studied. [ABSTRACT FROM AUTHOR]

Acyclic and macrocyclic compounds having different numbers of pyrimidine fragments and nitrogen atoms in the polymethylene bridges or in substituents at the pyrimidine rings reacted with 2,3,5,6-tetrachloro-1,4-benzoquinone and 1,4-benzoquinone according to the charge transfer scheme to give products with an ionic structure. The reaction was accompanied by protonation of nitrogen atoms in the polymethylene bridges or in substiuents at the pyrimidine rings and reduction of 2,3,5,6-tetrachloro-1,4-benzoquinone or 1,4-benzoquinone to 2,3,5,6-tetrachlorobenzene-1,4-diol or benzene-1,4-diol, respectively. The isolated products are dielectrics. [ABSTRACT FROM AUTHOR]

Methyldichlorosilanes with fluorinated cyclic substituents at silicon are prepared by the reaction of hydrosilylation of the corresponding hexafluoroolefins with methyldichlorosilane. [ABSTRACT FROM AUTHOR]