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The alkylation of aromatic hydrocarbons with haloalkenes in the presence of acid catalysts makes it possible to obtain haloalkylaromatic compounds with a halogen atom in a strictly defi ned position in the side chain [1][2][3]. The products of this reaction are promising raw material for the preparation of diverse diffi cultly available organic substances. In this connection in extension of study [4] we investigated the dehydrohalogenation of haloalkylarenes with KOH solution in ethylene glycol in order to evaluate the opportunity of preparation of alkenylaromatic hydrocarbons of a defi nite structure.The dehydrohalogenation of [2-chloro(bromo)propan-1-yl]benzene afforded allylbenzene, (1Z)-and (1Е)-prop-1-en-1-ylbenzenes in the ratio 1 : 6 : 93.The dehydrochlorination of (1-chloropropan-2-yl) benzene led to the formation of a chromatographically pure prop-1-en-2-ylbenzene, and at the dehydrohalogenation of (1-bromo-and 1-iodopropan-2-yl)benzenes alongside the prop-1-en-2-ylbenzene the (1Е)-prop-1-en-1-ylbenzene was obtained (Scheme 1).Expectedly the (2-methyl-1-chloropropan-2-yl) benzene did not suffer the dehydrochlorination. Unexpectedly dehydroiodination also failed with the 1-(1-iodopropan-2-yl)naphthalene. We succeeded to obtain the 1-(1-prop-1-en-2-yl)naphthalene from the 1-(1-iodopropan-2-yl)naphthalene only by pyrolysis of the 1-(1-acetoxypropan-2-yl)naphthalene that was the product of iodine substitution by an acetoxy group (Scheme 2). The dehydrohalogenation of 1,4-dimethyl-2-[2-chloro(bromo)propan-1-yl]benzenes furnished the 1,4-dimethyl-2-[(1Е)-prop-1-en-1-yl]benzene in a nearly quantitative yield.For the dehydrohalogenation of the other haloalkylarenes we used the mixtures of the alkylation products of methyl-, ethyl-, and isopropylbenzenes with allyl chloride and bromide in the presence of Lewis acids. These products were mixtures of o-, m-, and p-(2-halopropan-1-yl) derivatives of alkylarenes.Dehydrohalogenation procedure. To a solution of 0.12 mol of KОН in 25 ml of di(ethylene glycol) was added 0.1 mol of haloalkylarene, and the mixture was boiled for 1.5 h. The reaction products were extracted into benzene. The extract was washed with water, benzene was distilled off, the residue was subjected to rectifi cation.From (1-chloropropan-2-yl)benzene we obtained 11.4 g (97%) of a mixture of bp 193-196°С, d 4 20 0.9068, n D 20 1.5498. (1Е)-Prop-1-en-1-ylbenzene was isolated of bp 73.5°С (20 mm Hg), d 4 20 0.9083, n D 20 1.5470. МR D 41.20, calc. 39.69. IR spectrum, ν, cm -1 : 965 s (trans-С=С), 770, 730 s (monosubstitution in benzene). The physicochemical constants were consistent with the published data [5].The dehydrohalogenation of the mixture of (2-chloropropan-1-yl)toluenes gave 12.8 g (97%) of a mixture of 1-methyl-2-[(1Е)-prop-1-en-1-yl]benzene (43-47%) and 1-methyl-3-and 1-methyl-4-[(1Е)-prop-1-
The effect of nitrogen-containing phenol oligomers on the viscosity-temperature properties of base motor oil is studied. It is found that the products of oxypropylation of phenol and monoalkylphenols (alkyl chain length -C 8 -C 12 ) in the presence of benzoguanamine, as well as oxypropylated benzoguanamine have a positive effect on these properties. It is also found and scientifically validated that the viscosity -temperature properties of base-oil compositions are affected by the concentration, component composition, and thickening power of oligomers in oil.Phenol oligomers or phenol compounds (alkylphenols with alkyl groups of various length and structure) and formaldehydes, which contain heteroatoms (nitrogen, sulfur, phosphorus), are used as multi-purpose and multi-functional oil additives. TsIATIM-339, TsIATIM-339s, VNIINP-360, VNIINP-370, VNIINP-715, Borin, IKhP-101, BFK, BFKu, etc. are industrial grades of alkylphenol detergent, antioxidative, and depressor additives. Some of them (TsIATIM-339, TsIATIM-339s, VNIINP-360, and IKhP-101) also possess antiware and anticorrosion properties [1]. Various salts (calcium, barium, zinc) of the condensation products of alkylphenols with formaldehyde and amines make up the greater part of these additives. As a rule, additives of this type do not possess thickening power, and do not improve the viscosity-temperature properties of base oils. The nitrogen-and sulfur-containing additive IKhP-21, which can be produced by reacting phosphorus pentasulfide as a product of alkylphenol condensation with formaldehyde, exhibits antioxidative properties and high thermal stability [2].In the search for new nitrogen-containing phenol oligomers possessing additional functional properties, we synthesized oil-soluble oligomeres by reacting phenol or its compounds (monalkylphenols with the C 8 -C 12 alkyl groups) with benzoguanamine (1,3-diamine-5-phenyl-2,4,6-triazine), and by reacting between benzoguanamine with propylene oxide, as well mixtures of the latter with polypropylene glycol [3, 4].
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