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71.
二甲基烯丙基对甲基苄基氯化铵的合成与表征   总被引:1,自引:0,他引:1  
赵文善  于丽  严军辉  张曦霞 《化学研究》2006,17(4):54-55,59
以对甲基氯化苄与二甲基烯丙基胺为原料合成了二甲基烯丙基对甲基苄基氯化铵,考查了光照、氮气保护、避光、温度、原料配比、反应时间和不同溶剂等因素对反应的影响,通过四苯硼钠的定量分析确立了最佳反应条件,并对产物的结构进行了表征.  相似文献   
72.
相转移催化元素硫的歧化反应   总被引:1,自引:0,他引:1  
本工作将相转移催化(PTC)应用于元素硫歧化反应,大大降低了反应温度,提高了反应速度。该反应被证实与熔态硫在水溶液中的歧化相同,即4S+6OH~-=2S~(2-)+S_2O_3~(2-)+3H_2O。比较了四乙基铵、四丁基铵、十六烷基三甲基铵和三辛基甲基铵四种相转移催化剂及四氯乙烯、二甲苯和四氯乙烷三种溶剂的影响。讨论了本体系相转移催化的证据。为改进以元素硫歧化反应为基础的提取冶金过程提供了依据。  相似文献   
73.
金文虎  金晶  冀亚飞 《有机化学》2007,27(12):1605-1608
以2,3,4,5-四甲氧基甲苯为原料, 经溴化、生成格氏试剂后在碘化亚铜存在下与(E)-4-氯-2-甲基-1-苯磺酰基-2-丁烯缩合得到合成辅酶Q10的关键中间体6-(E-3'-甲基-4'-苯磺酰基-2'-丁烯基)-2,3,4,5-四甲氧基甲苯. 此中间体与茄尼基溴缩合、脱砜基化反应和氧化三步反应, 最终制得标题化合物辅酶Q10, 以2,3,4,5-四甲氧基甲苯计总收率达31.3%.  相似文献   
74.
A novel perfluoroalkyl-containing quaternary ammonium salt 5 was designed and synthesized. Consequently, the antimicrobial activities of compound 5 were measured with Escherichia coli 8099 as a Gram-negative strain and Staphylococcus aureus ATCC 6538 as a Gram-positive strain. Both the minimum inhibitory concentration (MIC, the lowest concentration of compound 5 that inhibits microbial growth) values of quaternary ammonium salt 5 against Escherichia coli 8099 and Staphylococcus aureus ATCC 6538 were 7.8 μg/ml.  相似文献   
75.
A combined method for determination of the standard enthalpies of formation of nitroform and its salts was proposed. The enthalpies of dissolution of nitroform and its ammonium, hydrazinium, guanidinium, and potassium salts in water were measured. The enthalpy of combustion of hydrazinium salt of nitroform was determined by a combustion calorimetry, and its standard enthalpy of formation was calculated. The enthalpy of formation of trinitromethyl anion in indefinitely diluted aqueous solution −24.94±0.79 kJ mol−1, was calculated on the basic of the data obtained for enthalpies of formation and dissolution of ammonium and hydrazinium salts of nitroform. Standard enthalpies of formation of nitroform and its salts were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1998.  相似文献   
76.
The ion-exchange equilibrium in network polymers obtained from cis-2,8,14,20-tetraphenyl-4,6,10,12,16,18,22,24-octahydroxycalix[4]arene by template synthesis on cations Na+, K+, and Ba2+ as matrices was studied. The selectivity coefficients of ion exchanges Ba2+-H+, Na+-H+, K+-H+, Na+-K+, and Na+-NH4 + were determined. The template synthesis enhanced the affinity of the polymers to matrix-forming cations by 6–8 kJ mol−1. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1919–1922, August, 2005.  相似文献   
77.
1 INTRODUCTION The crystal structures of several tetrahalogeno-mercurates (II) have been reported with a wide va-riety of stereochemical arrangements[1, . These stu- 2]dies have shown that the Hg atom…  相似文献   
78.
Equilibrium constant (K), enthalpy change (H), and entropy change (S) values have been determined calorimetrically at 25°C in 90%MeOH 10%H2O (v/v) for the interactions of pyridino-18-crown-6 (P18C6) and diketopyridino-18-crown-6 (K2P18C6) with perchlorate salts of ammonium, benzylammonium,-phenylethylammonium,-phenylethylammonium, and-(1-naphthyl)ethyl-ammonium cations. The crystal structure of the complex of P18C6 with benzylammonium perchlorate was determined by X-ray crystallography. The1H 1D and 2D NMR spectra of some of these complexes were used to elucidate their structural features in solution. The logK values for the interaction of the ammonium cations with P18C6 are larger than those with K2P18C6, probably due to the higher degree of structural flexibility of P18C6. Ligand K2P18C6 displays appreciable - interaction with the-(1-naphthyl)ethylammonium cation, but not with the-phenylethylammonium cation.- interaction between ligand and cationSupplementary Data relating to this article are deposited with the British Library as Supplementary Publication No SUP 00000 (22 pages)  相似文献   
79.
Synthesis and properties of chiral ammonium-based ionic liquids   总被引:1,自引:0,他引:1  
New chiral ammonium-based ionic liquids containing the (1R,2S,5R)-(-)-menthyl group can be easily and efficiently prepared under ambient conditions. The preparation and characterization of trialkyl[(1R,2S,5R)-(-)-menthoxymethyl]ammonium salts is reported. The salts have been demonstrated to be air- and moisture-stable under ambient conditions and can be readily used in a variety of standard experimental procedures. The single-crystal X-ray structure of butyldimethyl[(1R,2S,5R)-(-)-menthoxymethyl]ammonium chloride has been determined. The chiral, room-temperature ionic liquids have been characterized by physical properties such as specific rotation, density, viscosity, thermal degradation, and glass transition temperature. Trialkyl[(1R,2S,5R)-(-)-menthoxymethyl]ammonium chloride prototype ionic liquids have also been found to exhibit strong antimicrobial and high antielectrostatic activities.  相似文献   
80.
合成了硫氰酸合希土酸四丁基季铵盐配合物,测定了它们的远红外光谱及部分配合物的中红外光谱,结果表明,配合物中的NCS-是以氮原子与Ln3+配位。用X射线单晶衍射法测定了[(n-C4H9)4N]3Nd(NCS)6晶体的结构,结果表明,该晶体属单斜晶系,Cc空间群,晶胞参数为:a=25.188(8)Å,b=13.320(6)Å,c=25.322(8)Å,β=121.30(2)°,晶胞体积V=7258.9Å3,每一晶胞中有四个配合物分子,中心离子Nd3+与六个来自NCS-的氮原子配位,这六个氮位于配位正八面体的六个顶角上,构成配阴离子Nd(NCS)63-,它与三个[(n-C4H9)4N]+以静电引力结合成中心分子,所以晶体为离子型晶体。  相似文献   
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