Synthesis and Properties of Hydroxyl-Containing Ionic Liquids

Hydroxyl-containing ionic liquids were synthesized by quaternization of 1,2-dimethyl-1H-imidazole, N-methylpyrrolidine, and pyridine with 2-chloroethanol or 6-chlorohexan-1-ol, followed by exchange of chloride ion for bis(trifluoromethanesulfonyl)azanide, and their properties were studied.     

Hydroxyl-containing imidazolium ionic liquids

A number of imidazolium ionic liquids with bis(trifluoromethylsulfonyl)imide anion containing a ω-hydroxyalkyl substituent of different lengths in the cation (n_С = 2–8) were synthesized. The properties of the obtained liquids were investigated by DSC, TGA, IR, and NMR spectroscopy. Their thermal stability was studied; melting points, viscosity, and volatility in vacuum were measured. The possibility of using synthesized ionic liquids as heat carriers under high vacuum conditions is demonstrated.     

Controlled radical polymerization of styrene mediated by dithiobenzoates as reversible addition-fragmentation chain-transfer agents

The radical polymerization of styrene at 60 and 80°C mediated by benzyl dithiobenzoate and poly(styrene dithiobenzoate) as reversible addition-fragmentation chain-transfer agents has been studied. It has been shown that both agents are characterized by high chain-transfer constants and provide control over molecular-mass characteristics of polymerization products. The number-average molecular mass of polystyrene linearly grows with conversion, and the polymers are characterized by low values of polydispersity indexes. It has been demonstrated that the rate of polymerization significantly decreases with an increase in the concentration of reversible addition-fragmentation chain-transfer agents. This effect is typical of styrene polymerization mediated by dithiobenzoates. The possible reasons for this phenomenon are discussed.     

Pyrimidines

A new method was developed for the preparation of 1,3-diarylbenzo[f]quinazolines by condensation of-naphthylamine, an aromatic aldehyde, and ammonia and subsequent dehydrogenation of the initially formed dihydro derivatives.See [1] for communication LIV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 100–104, January, 1978.     

Oxidative reactions of azines. 2.* Synthesis and molecular structure of 3,4-dihydroxy-1-methyl-2-oxo-4-(γ-pyridyl)piperidine

The oxidative ketodihydroxylation of a 1,2,3,6-tetrahydropyridine is reported. Using PMR and x-ray structured analysis, the product was shown to be 3,4-dihydroxy-1-methyl-2-oxo-4-(-pyridyl)piperidine.For communications 1, see [1].Russian University of National Friendship, Moscow 117198. L. Ya. Karpov Physicochemical Science Research Institute, Moscow 103603. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1372–1375, October, 1996. Original article submitted June 20, 1996.     

Specific features of reversible <Emphasis Type="Italic">E</Emphasis>—<Emphasis Type="Italic">Z</Emphasis>-photoisomerization of crown-containing 4-styrylpyridine complexes with various cations

The reversible photochemical E—Z-isomerization of crown-containing 4-styrylpyridine was studied. The reaction was carried out in the presence of alkaline-earth metals capable of forming complexes with the crown-ether fragment and heavy metal perchlorates (Hg²⁺, Cd²⁺) that are able to coordinate the nitrogen atom of the heterocyclic residue. The influence of complex formation on the E—Z-photoisomerization was determined by electronic spectroscopy and ¹H NMR spectroscopy. The studies performed confirm that the E—Z-photoisomerization can be controlled using supramolecular complex formation.     

Chemical Properties of 6-Methyluracil-5-carbaldehyde Oxime

Russian Journal of Organic Chemistry - Oxidative chlorination of 6-methyluracil-5-carbaldehyde oxime in a two-phase system gave 7V-hydroxy-6-methyluracil-5-carboximidoyl chloride, and its...     

Second-Order Necessary Optimality Conditions in Optimal Impulsive Control Problems

Impulsive optimal control problems are studied. Under the Frobenius conditions, second-order necessary optimality conditions are proved without any a priori normality assumptions.     

Longitudinal Structure Function FL at Small x Extracted from the Berger–Block–Tan Parametrization of F2

JETP Letters - The longitudinal structure function FL(x, Q2) is extracted at low values of the Bjorken variable x from the Berger-Block-Tan parametrization of F2(x, Q2). The obtained structure...     

Steady-State Heat Distribution in Bimaterial with an Interface Crack: Part 1

Computational Mathematics and Mathematical Physics - The transmission problem describing a steady-state temperature distribution in a plane consisting of two half-planes occupied by different...