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2-Methyl-4-(4-pyridyl)-3-butyn-2-ol ( 2 ) was prepared in 70% yield by the reaction of 4-bromopyridine with 2-methyl-3-butyn-2-ol in diethylamine in the presence of bis(triphenylphosphine)palladium(II) chloride and copper(I) iodide. Removal of the protective group in 2 by refluxing with sodium hydroxide in toluene yields (90%) 4-ethynylpyridine ( 3 ). Oxidative coupling of 3 in pyridine by dioxygen in the presence of copper(I) chloride produces a 92% yield of 1,4-bis(4-pyridyl)butadiyne. 相似文献
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A. V. Shastin L. B. Romanova L. T. Eremenko V. V. Zakharov G. V. Lagodzinskaya G. G. Aleksandrov I. L. Eremenko 《Russian Chemical Bulletin》2006,55(8):1452-1454
1,4-Bis(chloromethyl)-and 1,4-bis(bromomethyl)cubanes were synthesized by the reactions of triphenylphosphine with CCl4 and
NBS, respectively. The structures of the compounds were studied by X-ray diffraction analysis.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1399–1401, August, 2006. 相似文献
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Conclusions 1,2-Bis(B-amino-o-carboranyl)ethane and 1,4-bis(B-amino-o-carboranyl)benzene were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1669–1670, July, 1976. 相似文献
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M. V. Sigalov E. Yu. Shmidt S. E. Korostova B. A. Trofimov 《Chemistry of Heterocyclic Compounds》1991,27(8):832-836
In the reaction of 1,4-bis(1-vinyl-2-pyrrolyl)benzene with hydrogen chloride and hydrogen bromide the hydrogen halide adds at the vinyl groups, and -protonation takes place in both pyrrole rings. In reaction with the superacidic system HSO3F+SbF5 (in SO2ClF) position 5 of one heterocycle and position 4 of the other are protonated with retention of the vinyl groups.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1041–1045, August, 1991. 相似文献
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The polymerization of acrylonitrile (AN) initiated by 1,4-dimethyl-1,4-bis(p-nitrophenyl)-2-tetrazene (Ie) was studied in dimethylformamide (DMF) at high temperature. The polymerization proceeds by a radical mechanism. The rate of polymerization is proportional to [Ie]0.64 and [AN]1.36. The overall activation energy for the polymerization is 21.5 kcal/mole within the temperature range of 115-130°C. The chain transfer of Ie was also undertaken over the temperature range of 120-135°C. The activation parameters for the decomposition of Ie at 120°C are kd = 2.78 × 10?6 sec?1, ΔH? = 40.8 kcal/mole, and ΔS? = 19.5 cal/mole-deg, respectively. 相似文献
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K. A. Andrianov V. I. Pakhomov V. M. Gel'perina 《Chemistry of Heterocyclic Compounds》1968,4(3):410-411
The ammonolysis of 1,4-bis(dimethylchlorosilyl)benzene with ammonia forms heterocyclic compounds of low molecular weight. The main reaction product is the crystalline [CH3)2SiC6H4Si(CH3)2NH]4, which polymerizes on heating with the formation of polymers possessing a relative viscosity of 0.15–0.4. 相似文献
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Abstract The polymerization of styrene (St) initiated by 1,4-dimethyl-1,4-bis(p-anisyl)-2-tetrazene (1a) was studied kinetically in benzene. The polymerization proceeds through a radical mechanism. The rate of polymerization is proportional to [1a]0.5 and [St]1.0. The overall activation energy for the polymerization is found to be 81.2 kJ/mol within the temperature range of 65 to 80°C. The activation parameters for the decomposition of 1a at 70°C are kd = 1.88 × 10?5s?1, δH? = 133.1 kJ/mol, and δS? = 29.9 J/mol·deg. 相似文献
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E. N. Rasadkina P. V. Slitikov A. I. Stash E. E. Nifant’ev 《Russian Chemical Bulletin》2005,54(2):449-451
1,4-Bis(hydroxymethyl)benzene undergoes bisphosphorylation with P(NEt2)3 at room temperature. The reaction produces no cyclic structures.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 440–442, February, 2005. 相似文献
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By adopting “grafting from” manner, polystyrene was grafted onto the surface of silica gel particles with an average size
of 125 μm in a solution polymerization system, and grafted particle PSt/SiO2 was prepared. Using 1,4-bis (chloromethoxy) butane (BCMB, it is nontoxic.) as chloromethylation reagent, chloromethylation
reaction for the grafted particle PSt/SiO2 was performed in the presence of Lewis acid catalyst SnCl4. At the same time, cross-linked styrene-divinylbenzene copolymer (CPS) microsphere also was chloromethylated with the same
reagent as PSt/SiO2, so that two kinds of chloromethylated polystyrene particles were obtained, and they are chloromethylated grafted particle
(CMPS/SiO2) and chloromethylated cross-linked polystyrene (CMCPS) microsphere, respectively. The chemical structures and compositions
of the two particles were characterized using Fourier transform infrared and Volhard method. The effects of various factors
on the chloromethylation reactions were mainly investigated. The experimental results show that the process to prepare the
two kinds of chloromethylated polystyrene particles not only has the character of environment friendness and low cost but
also is convenient to control via adjusting various reaction conditions. The main reaction conditions affecting the chloromethylation
reactions are reaction time, the added amount of BCMB, and the used amount of solvent and catalyst. They influence the reaction
in two respects: (1) the chloromethylation degrees of polystyrene are different under different conditions; (2) Friedel–Crafts
cross-linking reaction between polystyrene macromolecules is accelerated or inhibited under different conditions (for CPS
microsphere, this cross-linking reaction also is called the additional cross-linking). Under suitable conditions, the two
kinds of chloromethylated polystyrene particles with a high chlorine content (about 17%, this chlorine content was calculated
based on polystyrene weight) can be gained using SnCl4 as catalyst and CH2Cl2 as solvent at room temperature for 10 h and basically without cross-linking or additional cross-linking. 相似文献
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An approach for the total synthesis of 1,4-bis(2-(tert-butyl)-2H-tetrazol-5-yl)buta-1,3-diyne was reported. Developed approach to the synthesis of 1,4-bis(2-(tert-butyl)-2H-tetrazol-5-yl)buta-1,3-diyne can be used for obtaining different 2,5-bis(tetrazol-5-yl)-disubstituted five-membered heterocycles (e.g. thiophenes, pyrroles, furans etc.), as well as tetrazole-containing monomers for the synthesis of new types of electroconductive and high energetic polymers. 相似文献
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R. G. Petrova T. D. Churkina Sh. A. Karapet'yan R. Kh. Freidlina 《Russian Chemical Bulletin》1974,23(11):2425-2429
Conclusions The radical chain isomerization of aliphatic ketone mercaptals under the influence of tert-butyl peroxide has general significance. Both possible migration paths of the thiol groups are realized in the case of the unsymmetrical mercaptals of 2, 2-bis(n-butylthio)hexane and 2,2-bis(n-butylthio)butane, with the formation of both 1,2-bis(n-butylthio)alkanes and 2,3-bis(n-butylthio)alkanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2517–2521, November, 1974.The authors express their gratitude to V. I. Dostovalova for assistance in interpreting the NMR spectra and valuable discussion. 相似文献
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Ying-Hung So 《Journal of polymer science. Part A, Polymer chemistry》1997,35(11):2143-2145
High molecular weight poly(phenylenebenzobisoxazole) (PBO) was synthesized from 1,3-diamino-4,6-dihydroxybenzene dihydrochloride (1) and 1,4-bis(trichloromethyl)benzene (3) in polyphosphoric acid (PPA) or a mixture of PPA and methanesulfonic acid. When PPA was used as the solvent, 3 was first converted in situ to terephthalic acid before 1 was added to minimize degradation of 1. Compound 3 did not need to be sealed from atmospheric moisture because the trichloromethyl groups were not moisture sensitive. It was not necessary to use micronized 3. Adjustment of P2O5 content was optional for this reaction because no water was liberated from the condensation of 1 and 3. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2143–2145, 1997 相似文献
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《Tetrahedron letters》2019,60(22):1493-1497
A simple and efficient method was developed for the synthesis of 1,4-thiazin-2-one O-(tert-butyl) oximes and benzo[b][1,4]thiazin-2-one O-(tert-butyl) oximes from N-tert-butoxy acyl imidoyl bromides and 2-aminothiols in the presence of K2CO3/SiO2. Twenty five novel compounds were readily synthesized in excellent yields using this procedure. The products possessed Z-stereochemistry with regard to the CN double bond. The reaction proceeded with initial substitution of bromine in the N-tert-butoxy acyl imidoyl bromides by mercapto groups in the presence of K2CO3/SiO2, and subsequent intramolecular Schiff base formation. 相似文献