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91.

The reaction of congeners of Sovol technical mixture of polychlorobiphenyls with polyethylene glycols was studied. Mixtures of hydroxy and mono(polyethylene glycol)oxy derivatives were obtained. The mixtures synthesized, which are of low hazard, were used as additives to industrial oil to improve its tribological characteristics.

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92.
Conditions have been found for the regiodirected cyclization of 2-aminobenzimidazoles using ethyl 3-oxo-3-polyfluoroalkyl-2-ethoxymethylidenepropionates at the ethoxymethylidenefluoroacyl fragment to give ethyl pyrimidobenzimidazole-3-carboxylates.  相似文献   
93.
The synthesis of iodo(perfluoroalkyl)epoxides by radical addition of perfluoroalkyl iodides to allyl glycidyl ether and 1,2-epoxydec-9-ene is described. Dehydroiodination of additional products upon treatment with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) gives unsaturated products. The use of Bu3SnH/Bz2O2 as a reduction reagent of iodo(perfluoroalkyl)allyl glycidyl ethers allows to save oxirane ring. Cationic polymerization of saturated or functional (with iodine or double bond) fluoroalkyl oxiranes under action of catalytic amount of BF3.Et2O proceeds only on epoxide group. In case of poly(9-iod-10-(perfluoroalkyl)-1,2-epoxyalkane) iodine atoms are removed by standard zinc reduction.  相似文献   
94.
The reaction of oxides of internal perfluoroolefins 1-3 with urea gave two kinds of novel fluorine containing N-heterocyclic compounds depending on the solvent nature: 1,5-bis(perfluoroalkyl)tetraazabicyclo[3.3.0]octane-3,7-diones 4a-c and 2-amino-5-fluoro-4,5-bis(perfluoroalkyl)-4,5-dihydrooxazol-4-ols 7a-d. Use of polar dimethylsulfoxide, N,N-dimethylacetamide and acetonitrile afforded glycolurils 4a-c in moderate yields. In dioxane, unexpected cyclization occurred resulting in oxazolines 7a-d in high yields. A similar reaction of oxiranes 2, 3 with urea in aqueous dioxane gave mixtures of 4,5-dihydroxy-4,5-bis(perfluoroalkyl)imidazolidine-2-ones 9b, c, glycolurils 4b, c and oxazolines 7b-d. The molecular structure of trans-isomers of oxazoline 7b and imidazolidine 9b has been established by X-ray crystallography.  相似文献   
95.
Russian Journal of Applied Chemistry - Reactions of commercial polychlorobiphenyl mixtures with alkali in polyalkanolamines were studied. The major reaction products are hydrophilic mixtures of...  相似文献   
96.
Chemistry of Heterocyclic Compounds - We propose different methods for the synthesis of 4-hydroxyimino-5-polyfluoroalkylpyrazol-3-ones. The simplest and most convenient procedure relies on...  相似文献   
97.
Ethyl acetoacetate was acylated with 3,4,5-trifluoro-2,6-dimethoxybenzoyl chloride to give, for the first time, ethyl 3-oxo-2-(3,4,5-trifluoro-2,6-dimethoxybenzoyl)butyrate and its copper chelate. The title compound was used for the synthesis of 6,7,8-trifluoro-5-hydroxy-2-methylchromone, 1-(3,4,5-trifluoro-2,6-dimethoxyphenyl)butane-1,3-dione, and its copper chelate.  相似文献   
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