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1.
1,2-Dimethyleneoctafluorocyclohexane has been prepared by the pyrolysis of 2-chloro-methyl-1-methyloctafluorocyclohexane. Free radicals initiate the polymerization of the diene in both bulk and emulsion systems to give a highly crystalline (mp 214–218°C) polymer that has an all-cis 1,4-structure. The polymer is insoluble in common laboratory solvents, but will dissolve in perfluorokerosene above 175°C and in 2,5-dichlorobenzo-trifluoride above 150°C. This diene is not polymerized by cationic, anionic, or Ziegler-Natta catalysts. The diene is readily copolymerized with many common monomers to give soluble, high molecular weight polymers. Relative reactivity ratios have been measured with styrene by the Fineman and Ross method and Qe parameters for the diene have been calculated.  相似文献   

2.
A number of 2-substituted 1,4-dioxanes were synthesized from -chloroethyl glycidyl ether, the appropriate alcohols, and diethylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 161–163, February, 1973.  相似文献   

3.
The two title monomers were synthesized. In both cases the key cyclobutane intermediates were obtained by cycloaddition of allene to acrylonitrile or chloromaleic anhydride. These two new monomers proved to be highly reactive in free radical polymerization, and each polymerized spontaneously in air at room temperature. Linear polymers were prepared in dimethyl sulfoxide solution at 35° with AIBN and UV light. At higher temperatures crosslinking became a problem in some instances. The structure of the polymers derived from 1,4 polymerization in the diene portion of the monomers was confirmed by 13C-NMR, 1H-NMR and IR spectra. Copolymers were prepared with methyl methacrylate, styrene, and p-methoxystyrene and were always rich in the methylene-cyclobutene monomers used. Films of homopolymers and copolymers could be cast from chloroform solution.  相似文献   

4.
Radiation-induced polymerization of 1,2-epoxy-4-epoxyethylcyclohexane (EECH) has been carried out at different temperatures in solid and liquid states. Activation energy was calculated from Arrhenius plot and ionic mechanism was proposed. Molecular weights for some polymer samples were determined by cryscopic method and compared with their intrinsic viscosities. Cationic polymerization of EECH initiated by BF3 · O(C2H5)2 and anionic polymerization initiated by NaOH are also studied. Two epoxy rings can be opened for polymerization selectively by radiation, but not by chemical initiators. The expected polyether structure was observed from the IR spectrum. Polymers obtained were shown to be amorphous from X-ray photographs.  相似文献   

5.
1,2-Diketone moiety-bearing monomer 1-phenylbut-3-ene-1,2-dione, an analogue of phenyl vinyl ketone, was synthesized from 4-chlorobutyryl chloride in a 29 % overall yield in five steps. Following acylation of benzene with 4-chlorobutyryl chloride, the resulting α-methylene group was oxidized to 1,2-diketone in three steps: successive bromination, substitution with lithium hydroxide, and oxidation of α-hydroxyketone with potassium dichromate. The final step was dehydrochlorination of 4-chloro-1-phenyl-butane-1,2-dione. The attempted copolymerization of this monomer with styrene, using AIBN as the initiator, was unsuccessful.  相似文献   

6.
Reactions of dimedone and ethyl acetoacetate with 1,2-epoxy-3-chloropropane in the presence of K2CO3 in DMSO medium were investigated. The reaction of 1,2-epoxy-3-chloropropane with ethyl acetoacetate afforded ethyl 5-hydroxy-2-methyl-5,6-dihydro-4H-pyran-3-carboxylate, with dimedone, 3-(1′,2′-epoxypropyloxy)-5,5-dimethyl-cyclohex-2-en-1-one.  相似文献   

7.
以(S)-苯丙氨酸为原料,经氨基保护、与对硝基苯酚成酯后与硫叶立德反应制得(S)-1-氯-3-叔丁氧酰胺基-4-苯基-2-丁酮(3);3经Meerwein-Poondrf-Verley还原、环合等反应合成了HIV-1蛋白酶抑制剂的关键中单体——(2S,3S)-1,2-环氧基-3-叔丁氧酰胺基-4-苯丁烷,总收率约45%,其结构经1H NMR和MS确证。  相似文献   

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9.
陈其杰  孔建设 《化学学报》1986,44(4):364-373
叙述了以1,1,1-三氯-2-乙酰氧基-3-硝基丙烷和1,1,1-三氯-2-肼基-3-硝基丙烷为原料,合成脂肪和芳香肼类、酰肼类、偶氮类以及腙类等四十三个新化合物的方法,将N-芳基-N'-[2-(1,1,1-三氯-3-硝基)丙基]肼用N-溴代丁二酰亚胺氧化成1,1-二氯-2-芳偶氮基-3-硝基丙烯后,不经分离直接加入过量的醇和定量的水继续反应,可方便地获得β-硝基丙酮酸酯腙类化合物,收率达60%以上。初步抑菌活性测定结果表明,大多数化合物呈现不同程度的抑菌活性,其中以肼类和偶氮类化合物的活性最高,丙酮酸酯腙类化合物次之。  相似文献   

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The synthesis of a new ionic liquid-type monomer has been performed by association of a methacrylate polymerizable group, a polar tri(ethylene oxide) (TEO) spacer, a trifluoromethane sulfonic (TFSI) anion and a free imidazolium (EMIm+) cation. The ionic liquid monomer (ILM) has demonstrated a good thermal stability and a high ionic conductivity around 2.1 × 10−3 S cm−1 at 20 °C. The corresponding homopolymer has shown an ionic conductivity closely related to the monomer (6.5 × 10−4 S cm−1 at 20 °C), which confirms the ILM as a valuable monomer for the formation of polymeric ionic liquid (PIL) materials.  相似文献   

13.
The hydrophobic ionic liquid 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl)imide was successfully used as solvent in group transfer polymerization of traditional methacrylates (methyl methacrylate, n‐butyl methacrylate, and benzyl methacrylate) and of ionic liquid methacrylates (ILMAs). This demonstrates that this ionic liquid makes reaction conditions, which do not require the use of ultra‐dried solvents. The ILMAs were N‐[2‐(methacryloyloxy)ethyl]‐N,N‐dimethyl‐N‐alkylammonium bis(trifluoromethylsulfonyl)imides bearing methyl, ethyl, propyl, butyl, or hexyl substituents. Increasing size of the alkyl substituent at the cation results in decreasing glass transition temperature in case of both ionic liquid methacrylates and polymers derived of them. Furthermore, the glass transition temperature is significantly higher for these polymers compared with the ionic liquid methacrylates, and the effect of glass transition temperature reduction with increasing size of the alkyl substituent is stronger for the polymers. A mechanism was proposed explaining the catalytic function of the ionic liquid used as solvent for polymerization. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2849–2859  相似文献   

14.
A facile synthesis of trans-3,4-dihydroxy-anti-1,2-epoxy-1,2,3,4-tetrahydro-7,12-dimethylbenz(a) anthracene 1 ; a highly carcinogenic metabolite of 7,12-dimethylbenz(a) anthracene (DMBA) have been described.  相似文献   

15.
Dehydration of (S)-3,5-dimethyl-1-hepten-3-ol gave: (3E)- (I) and (3Z)-(5S)-3,5-dimethyl-1,3-heptadienes (II) and 2-[(S)- 2-methylbutyl]-1,3-butadiene (III). 2-[(S)-1-Methylpropyl]-1,3-butadiene (IV) was also prepared similarly by dehydration of (S)-3,4-dimethyl-1-hexene-3-ol. Monomers I–IV we polymerized in the presence of the TiCl4–Al(i-C4H9)3 catalyst system and in emulsion with K2S2O8 as initiator. Monomer IV was also polymerized in the presence of butyllithium. Specific rotations of polymers are of the same order of magnitude as that of monomers, with exception of polymers prepared by stereospecific polymerization of (S)-I and (S)-II. The acetone-soluble fraction of these polymers has a molar rotation similar to that of monomer, while the acetone-insoluble part has a lower rotation ([M]D of monomer +53.2°; [M]D of polymer, +5.9°).  相似文献   

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A convenient method for the synthesis of 3-acyl-1,2-benzisoxazoles, which are unstable toward bases, is described. Base-catalyzed cyclization of 2-alkyl- and aryl-1,3-dithian-2-yl o-chlorophenylketoximes 4a-1 gave 3-(2-alkyl- and aryl-1,3-dithian-2-yl)-1,2-benzisoxazoles 8a-1 , which were converted into the corresponding 3-acyl-1,2-benzisoxazoles 1a-1.  相似文献   

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Pure liquid styrene, carefully purified and exhaustively dried, exhibits kinetic behavior under γ-irradiation that can best be described in terms of an ionic mechanism. This is based on the observed linear dependence of the rate of polymerization on the dose rate, the independence of molecular weight on the same parameter, and comparison with the thermal and ultraviolet initiated polymerization of monomer prepared under the same stringent conditions. The highest rate of conversion to polymer is 400%/hr. at a dose rate of 106 rads/hr., corresponding to a G(-monomer) ≈ 40,000.  相似文献   

20.
With the intention that annulation of carbo- or heteroaromatic rings at the 1,2-positions can activate 3-cyanoindolizines as 1,3-dipolar species, 6-cyanobenz[a]indolizines, pyridazino[4,5-a]indolizines and 5-cyano-1,3-diphenylthiopheno[3,4-a]indolizine were prepared. 6-Cyanobenz[a]indolizines smoothly -underwent 1,3-dipolar cycloaddition on to dibenzoylacetylene and diacetylacetylene to afford the corresponding indolizino[3,4,5-ab]isoindoles, whereas 5-cyano-1,4-diphenylpyridazino[4,5-a]indolizine reacted with dimethyl acetylenedicarboxylate to give the 1:2 adduct. Only a 3% yield of 5-cyano-1,3-diphenylthiopheno[3,4-a]indolizine formed upon phosphorus pentasulfide treatment of 1,2-dibenzoyl-3-cyanoindolizine.  相似文献   

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