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1.
研究了温度、时间、紫外光照射等对天然胶乳小分子模型物(2-甲基-2-丁烯乳液)氯化反应的影响,结果表明,在有紫外光照的条件下的氯化反应速率要快于无紫外光照的;温度对氯化反应有着一定影响,在50℃以下,随温度升高产物的氯含量越高,在50℃以上,对产物的氯含量的影响不大;当温度50℃,时间达到7个小时的产物的氯含量能达到6...  相似文献   

2.
刘文青  冷志光 《色谱》2003,21(4):424-426
建立了用毛细管气相色谱法测定芳樟醇合成工艺路线中过程样品组分含量的方法。采用HP-FFAP(30 m×0.32 mm i.d.×0.25 μm)毛细管柱,以氢火焰离子化检测器检测,N2为载气,流速0.6 mL/min ,分流比150∶1,并采用程序升温,以校正面积归一化法计算各组分的含量。在确定的色谱条件下,样品中各组分分离较好,分析周期仅18 min。含量在50%以上的1-氯代异戊烯、甲基庚烯酮、芳樟醇、去氢芳樟醇等主要组分含量测定的相对标准偏差小于0.5%,回收率为99.7%~100.9%。结合标  相似文献   

3.
4.
Summary C-alkylation of phenolic acridones with 1,4-dibromo-2-methyl-2-butene under different conditions was studied. Condensations with 1,3 dihydroxy-10-methyl-acridin-9(10H)-one gave an O-alkylated product together with rutacridone and isorutacridone through C-alkylation. The aluminiumoxide and the ion exchange resin method offered the best yields for rutacridone and isorutacridone, respectively. Attempts with 4-hydroxy-10-methylacridin-9(10H)-one yielded several O-alkylated products including a dimer.
Naturstoffchemie, 136. Mitt.: Eine kommode Synthese von Rutacridon und Isorutacridon
Zusammenfassung Die C-Alkylierung von phenolischen Acridonen mit 1,4-Dibrom-2-methyl-2-buten wurde unter verschiedenen Bedingungen studiert. Die Kondensation mit 1,3-Dihydroxy-10-methylacridin-9(10H)-on ergibt ein O-alkyliertes Produkt zusammen mit Rutacridon und Isorutacridon, die über eine C-Alkylierung entstehen. Die Aluminiumoxid- und die Ionenaustauscher-Methode lieferten die besten Ausbeuten an Rutacridon und Isorutacridon. Versuche mit 4-Hydroxy-10-methyl-acridin-9(10H)-on führten zu einigen O-alkylierten Produkten, darunter ein Dimeres.
  相似文献   

5.
用玻璃外循环无梯度反应器研究在Pt/Al2O3催化剂上丁烷、反-2-丁烯及顺-2-丁烯深度氧化的内扩散影响.测出催化剂有效因子η为0.42~1.27,并随反应温度升高而下降.用Runge-Kutta法计算氧在催化剂孔内压力分布,孔中心氧分压y0随内扩散影响加大而下降,在420℃y0如趋于零.  相似文献   

6.
Isothermal vapor-liquid equilibrium (VLE) data were measured for the binary system methanol and 2,3-dimethyl-2-butene at 343.15 K, 353.15 K, 363.15 K, 373.15 K, respectively. The measurements were carried out in a novel recirculation equilibrium equipment. Three activity coefficient models including Wilson, NRTL and UNIQUAC, as well as the Soave-Redlich-Kwong equation of state were used to correlate the experimental data. The correlation results showed that a good consistency between the experimental data and the Wilson model can be achieved.  相似文献   

7.
本文报道了利用McMurry反应,由丙酮还原偶联合成2,3—二甲基丁烯—2(DMB—2)的实验结果。实验考察了镁粉还原四氯化钛的时间、丙酮与四氯化钛之比等因素对DMB—2收率的影响。探讨了低价钛试剂活性物的价态与DMB—2收率之间的关系。实验表明,大部分DMB—2是在最初几分钟内生成的,每摩尔的低价钛试剂最多可转化9摩尔以上的丙酮。  相似文献   

8.
The reductive coupling of carbonyl compounds is an important method of carbon-carbon bond formation. The reaction can be used in both an inter-and intramolecular manner. It is important for the formation of olefins. Mukaiyama T., et al1 reported that the reductive coupling of ketones with TiCl4/Zn in tetrahydrofuran (THF) afforded the corresponding pinacols or olefins in high yields. The pinacols were obtained at 0℃. After heating, the deoxygenation reaction of pinacols afforded olefins2.…  相似文献   

9.
2-Methyl-1-naphthol is oxidized into 2-methyl-1,4-naphthoquinone (menadione) by air in the presence of vanadomolybdophosphoric heteropolyacids and their salts. The reaction proceeds in a biphasic system, and the yield of menadione is up to 85 %. The influence of the composition of the heteropolyacids on the rate and the selectivity of the reaction was studied, and the reaction mechanism was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1208–1211, July, 1994.  相似文献   

10.
新型双膦配体的合成及其在2-丁烯氢甲酰化反应中的应用   总被引:1,自引:0,他引:1  
合成了以联苯为骨架,以吲哚为取代基的双膦配体,并研究了该配体与Rh(acac)(CO)2原位生成的催化剂在2-丁烯氧甲酰化反应中的催化性能.考察了膦/铑比、反应温度、反应压力以及2-丁烯与Rh(acae)(CO)2摩尔比等因素对反应活性及区域选择性的影响.结果表明,在60℃反应时,醛的正异比高达28.5;当压力为2.0...  相似文献   

11.
3,3-Bis(phenylthio)-1,1,1,2,2-pentafluorobutane 1 was reacted with aryllithium reagents (6 equiv) in ether at low to room temperature for 1-6 h to provide 2-aryl-1,1,1-trifluoro-3-phenylthio-2-butene 2 in 80-96% yields. Bromination of 2 with NBS in acetonitrile at reflux for 1-7 h afforded the corresponding allylic bromides 3 in 61-96% yields. Treatment of 3 with MCPBA (1.5 equiv) in methylene chloride at reflux temperature for 1-12 h resulted in the formation of 1-aryl-1-trifluoromethylallenes 4 in 74-96% yields.  相似文献   

12.
WO3/SiO2催化剂上2-丁烯与乙烯歧化制丙烯   总被引:1,自引:0,他引:1  
采用浸渍法制备了WO3/SiO2催化剂,对其进行了UV-Vis DRS和NH3-TPD表征。将WO3/SiO2作为催化剂,以乙烯和2-丁烯为原料制备丙烯,考察了反应温度、质量空速等因素对歧化反应的影响。实验结果表明,催化剂的最佳WO3担载量为8 %;以8%WO3/SiO2 为催化剂,在反应温度473K~573K、压力3.0MPa、质量空速1.6h-1下,2-丁烯的转化率可保持在80%以上,丙烯的选择性大于89.2%。经过140h的稳定性实验,2-丁烯的转化率和丙烯的选择性略有下降,适当的提高反应温度(由473K增加到513K)可以恢复催化剂的活性。新鲜催化剂表面存在四面体、八面体六价钨物种和体相WO3,适当还原的W物种是歧化活性物种;W负载在催化剂表面引入了新的强酸中心,同时明显增加了总酸量。  相似文献   

13.
Using mass spectrometric technique, the effect of geometrical isomerism on the first and higher appearance energy values for C4H3 +, C4H7 + and C3H,3 + ions obtained from cis-2-butene andtrans-2-butene is reported. The structure in the ionization efficiency curves (studied for 9 eV above threshold) for the same ions obtained from the two isomers is reported and compared. It is believed that at threshold C4H7 + fragment is formed from the two isomers as methallyl ion. For C3H3 + fragment formed from the cw-isomer at threshold the proposed structure is the propargyl ion with ΔHf equal to 279-4 kcal/mole while for that ion obtained fromtransisomer the proposed structure is the allenyl ion with ΔHf equal to 296.6 kcal/mole.  相似文献   

14.
Selective methods were developed for the synthesis of 4-benzoyl-1-benzoylamino-3-(2-chlorophenyl)-2-cyano-1-methylthio-1-butene on the basis of the reaction of N-methylmorpholinium and piperidinium 5-benzoyl-4-(2-chlorophenyl)-3-cyano-6-hydroxy-6-phenyl-1,4,5,6-tetrahydropyridine-2-thiolates with methyl iodide. The structure of the product was established by X-ray crystallographic analysis.  相似文献   

15.
The molecular structure of 1-methyl-1-fluoroquasisilatrane (2-methyl-2-fluoro-1,3-dioxa-6-aza-2-silacyclooctane) MeFSi(OCH2CH2)2NH (I) is determined by single crystal X-ray diffraction at 100 K. The coordination polyhedron of the silicon atom in this molecule is a slightly distorted trigonal bipyramid with an NH group and a strongly electron-withdrawing fluorine atom in the axial positions, and two endocyclic oxygen atoms and a CH3 group in three vertices of the equatorial plane. The axial angle N→SiF is 171°. The length of the transannular donor-acceptor bond N→Si (2.058 Å) is as small as in 1-fluorosilatrane. The axial bond F-Si (1.660 Å) is longer than that in 1-fluorosilatrane and tetrahedral silicon compounds.  相似文献   

16.
Reactions of the ruthenium complexes [RuH(CO)Cl(PPh3)3] and [RuCl2(PPh3)3] with hetero-difunctional S,N-donor ligands 2-mercapto-5-methyl-1,3,5-thiadiazole (HL1), 2-mercapto-4-methyl-5-thiazoleacetic acid (HL2), and 2-mercaptobenzothiazole (HL3) have been investigated. Neutral complexes [RuCl(CO)(PPh3)2(HL1)] (1), [RuCl(CO)(PPh3)2(HL2)] (2), [RuCl(CO)(PPh3)2(HL3)] (3), [Ru(PPh3)2(HL1)2] (4), [RuCl(PPh3)3(HL2)] (5), and [RuCl(PPh3)3(HL3)] (6) imparting κ2-S,N-bonded ligands have been isolated from these reactions. Complexes 1 and 4 reacted with diphenyl-2-pyridylphosphine (PPh2Py) to give neutral κ1-P bonded complexes [RuCl(CO)(κ1-P-PPh2Py)2(HL1)] (7), and [Ru(κ1-P-PPh2Py)2(HL1)2] (8). Complexes 1-8 have been characterized by analytical, spectral (IR, NMR, and electronic absorption) and electrochemical studies. Molecular structures of 1, 2, 4, and 7 have been determined crystallographically. Crystal structure determination revealed coordination of the mercapto-thiadiazole ligands (HL1-HL3) to ruthenium as κ2-N,S-thiolates and presence of rare intermolecular S-S weak bonding interaction in complex 1.  相似文献   

17.
Microwave spectrum of 2-methyl-1,3-dioxane has been investigated in the frequency range 8–40 GHz. Rotational a-type and c-type transitions with J≤40 have been identified. Rotational constants A = 4658.122(2) MHz, B = 2503.221(1) MHz, C = 1783.950(1) MHz and centrifugal distortion constants for the ground vibrational state have been found. Dipole moment components μa = 1.43 ± 0.01 D, μc = 1.15±0.01 D and overall dipole moment μ = 1.84±0.02 D have been determined. The data obtained are in accord with the chair conformation of the molecule having equatorial arrangement of the methyl group. Original Russian Text Copyright ? 2006 by A. Kh. Mamleev, R. V. Galeev, L. N. Gunderova, M. G. Faizullin, and A. A. Shapkin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No.2, pp. 373–375, March–April, 2006.  相似文献   

18.
Syntheses of 2,5-bis(4-methyl-2-thienyl)thiophene 3 and 2,5-bis(4-methyl-2-thienyl)pyrrole 4 are described. The key step involves Stetter reaction between 4-methyl-2-thiophenecarboxaldehyde and divinyl sulfone. Cyclizaton of the resulting 1,4-bis-(4-methyl-2-thienyl)-1,4-butanedione 2 with Lawesson's reagent gives 2,5-bis(4-methyl-2-thienyl)thiophene 3, whereas condensation with ammonium acetate provides the 2,5-bis(4-methyl-2-thienyl)pyrrole 4.  相似文献   

19.
The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds.  相似文献   

20.
4-甲基-3-硝基苯甲腈和2-甲基-5-硝基苯甲腈是重要的有机合成中间体[1,2],因其芳环上具有硝基和氰基两个第二类取代基,同时又有一个可参与反应的甲基而使得这两个化合物在有机合成领域有着广泛的应用前景.芳环上的甲基可以氧化为酸,也可进一步反应形成酰氯、酯等功能基;芳环上的氰基可水解成羧基,也可以与叠氮钠在Lewis酸催化下形成具有生物活性的四唑衍生物;芳环上的硝基经还原可形成氨基,如4-甲基-3-硝基苯甲腈通过化学反应可环合形成药物中间体6-氰基吲哚[2~4].  相似文献   

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