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1.
合成了11种1,1'-双[1-(芳亚氨基)乙基]二茂铁(简称二茂铁双亚胺)(la—1k)和8种环汞化反应产物,用元素分析、IR、1HNMR确定了它们的结构;除1c外,其余均为新化合物。双亚胺的环汞化反应表明主要生成单汞化产物,且汞化反应发生在取代茂环的邻位,但产率较低。探讨了影响环汞化反应的因素。  相似文献   

2.
芳腈在温和条件下进行锆氢化反应,所得产物经水解得到芳醛;若经酰基化则得到N-酰基不饱和胺。后者不稳定,在室温下与甲醇发生加成反应得N-(α-甲氧基苄基)苯甲酰胺。过量的锆氢化试剂与芳腈反应,继之进行酰基化,得到二元酰基化产物,两个酰基分别加到腈基的碳与氮原子上。  相似文献   

3.
芳胺常压气相N-烷基化反应研究   总被引:1,自引:0,他引:1  
在固定床催化反应器中常压下研究了芳胺和醇的气相法N-烷基化反应。考察了γ-Al2O3系列催化剂的反应性能,筛选出了两种适用于苯胺N-甲基化反应且性能较好的催化剂。反应条件为:在甲醇和苯胺的摩尔比为31时,反应温度为280℃,液时空速为0.3h-1的条件下,苯胺转化率为99%,生成N,N-二甲基苯胺(DMA)的选择性为92%。研究了甲醇和芳环上不同位置取代的甲基苯胺的反应规律,其转化率顺序:苯胺≈对一甲苯胺≈间-甲苯胺>邻-甲苯胺。从C1到C4不同结构的醇和苯胺反应的规律研究,证明随醇中碳原子数目的增加,醇的反应活性降低,正构醇和苯胺反应和异构醇与苯胺反应随温度升高的变化趋势相反。  相似文献   

4.
张慧  曹卫国  陈杰  邓红梅 《有机化学》2008,28(4):705-712
2-芳基硫代芳胺的结构广泛存在于许多具有重要生理、药理活性的天然产物、药物以及材料当中, 研究此类结构的构建对这些化合物的合成路线设计可以提供新的思路. 传统合成2-芳基硫代芳胺, 常需多步骤或高温、强碱条件下进行, 能进行此类反应的反应物有限, 所得产物收率不高. 选用三氟乙酰基作为芳胺氮原子上的保护基, 利用三氟乙酰基的邻位促进效应, 并采用碘化亚铜/L-脯氨酸的催化体系, 在乙二醇二甲醚中, 碳酸钾为碱, 于60 ℃一步实现N-三氟乙酰基邻碘代苯胺与芳基硫酚的偶联, 以高产率获得了N-三氟乙酰基-2-芳基硫代芳胺. 反应条件温和, 催化体系价廉易得, 反应操作简便.  相似文献   

5.
陈林 《有机化学》2003,23(9):1017-1018
研究了N-芳亚甲基-2-丙烯-1-胺(1)与甲醇钠的反应,当甲醇钠过量,反应 时间足够长时,生成的主要产物是N-芳亚甲基-1-甲氧基-丙胺(2)。  相似文献   

6.
二乙胺基乙腈分別与苯邻二酰亚胺、丁二酰亚胺或邻-磺酰苯酰亚胺反应后,可生成相应的N-氰甲基苯邻二酰亚胺、N-氰甲基丁二酰亚胺,N-氰甲基邻磺酰苯酰亚胺及O-氰甲基邻磺酰苯酰亚胺。酰亚胺或磺酰苯酰亚胺的氰甲基化反应活性,随氮负离子的稳定性及其酸性增强而增大。  相似文献   

7.
用作芳基自由基来源的N-亚硝基乙酰芳胺与α-溴汞化羰基化合物一起加热时,生成溴化芳基汞,副产物及ESR研究说明反应为自由基过程.  相似文献   

8.
马正平  叶亚  陈秋云 《无机化学学报》2011,27(11):2251-2256
N-苯基二吡啶甲基胺和苯甲基溴在Cu(ClO4)2存在的条件下反应导致N-苯基二吡啶甲基胺的邻位苯甲基化和一个新的溴桥联的双核铜配合物的形成。实验结果显示阴离子显著影响反应的选择性,CuCl2和Cu(NO3)2不能提高N-苯基二吡啶甲基胺邻位苯甲基化的选择性。NMR和元素分析数据证实N-苯基二吡啶甲基胺邻位苯甲基化产物的形成。X-射线晶体结构数据表明溴桥联的双核铜配合物中铜原子被3个N原子,1个配位溴离子和1个μ2-桥联的溴结合形成扭曲的三角双锥的构型。研究结果表明Cu(ClO4)2可作为N-苯基二吡啶甲基胺邻位烷基化反应的催化剂。研究结果有助于设计新的选择性苯甲基化催化剂。  相似文献   

9.
在离子液体[bmim]Br中, 5,5-二甲基-1,3-环己二酮与N-芳亚甲基芳胺反应合成了一系列四氢吖啶-1,8-二酮衍生物, 该反应具有适应性广、产率高、污染少、环境友好等优点.  相似文献   

10.
研究了用在线固相萃取富集和高效液相色谱法测定卷烟主流烟气中的几种芳胺(苯胺、对甲基苯胺、2,4-二甲基苯胺、1-萘胺、2-萘胺和4-氨基联苯)的方法,样品中的芳胺用邻甲氧基酚衍生生成偶氮染料,偶氮染料用WatersXterraTMRP18色谱柱在线固相萃取富集,然后以WatersXterraTMRP18色谱柱为固定相,75%的甲醇(内含0.01mol/LpH=8的四氢吡咯-醋酸缓冲液)为流动相分离,二极管矩阵检测器检测;苯胺、对甲基苯胺、2,4-二甲基苯胺、4-氨基联苯、1-萘胺、2-萘胺的检出限分别为005、0.08、0.08、0.06、0.03和0.03μg/L。几种芳胺的相对标准偏差在2.2%~3.4%之间;标准回收率在89%~106%之间,方法用于卷烟主流烟气中几种芳胺的测定,结果令人满意。  相似文献   

11.
The reaction of 2-cyclopropylthiophene with mercuric acetate in methanol takes place only in the thiophene ring. 5-Methyl-2-cyclopropylthiophene undergoes mercuration in both the heterocyclic ring and in the three-carbon ring (the Levina reaction).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 175–179, February, 1984.  相似文献   

12.
In order to investigate the mechanism of mercuration reaction of substituted ben-zylideneanilines, kinetic measurements of these reactions at different temperatures (40-60℃) inmethanol-l,4-dioxane (1/1, V/V) were carried out and Hammett ρ value for C-phenyl substituentsof-0.61 for the N-(substituted benzylidene)-4-toluidine series was obtained. Thermodynamicparameters E_a, △S~≠ were obtained for the reaction of different. N-(substituted benzylidene)-4-toluidines. It was found that this ortho-mercuration was brought about by an internal cyclometal-lation process involving the imino-moiety.  相似文献   

13.
Both mercuration and bromination have been used for the polarographic analysis of isopropenyl esters in aqueous solutions. For mercuration, no disadvantages were found in comparison with the established methods [4,5] for the estimation of vinyl esters in methanol, due to either the lower rate of mercuration [5,22] or the expected lower stability of the depolariser formed in aqueous solution, the hemiacetal mercuric acetate addition product. At concentrations below 10?2 mol l?1, acetone did not interfere [38] with the determinations.  相似文献   

14.
The synthesis, structure, and photochemical behavior of the trans isomers of 4-(N-phenylamino)stilbene (1c), 4-(N-methyl-N-phenylamino)stilbene (1d), 4-(N,N-diphenylamino)stilbene (1e), and 4-(N-(2,6-dimethylphenyl)amino)stilbene (1f) are reported and compared to that of 4-aminostilbene (1a) and 4-N,N-dimethylaminostilbene (1b). Results for the corresponding 3-styrylpyridine (2) and 2-styrylnaphthalene analogues (3) are also included. The introduction of N-phenyl substituents to 4-aminostilbenes leads to a more planar ground-state geometry about the nitrogen atom, a red shift of the absorption and fluorescence spectra, and a less distorted structure with a larger charge-transfer character for the fluorescent excited state. Consequently, the N-phenyl derivatives 1c-e have low photoisomerization quantum yields and high fluorescence quantum yields at room temperature, in contrast to the behavior of 1a, 1b, and most unconstrained monosubstituted trans-stilbenes. The isomerization of 1c and 1d is a singlet-state process, whereas it is a triplet-state process for 1e, presumably due to a relatively higher singlet-state torsional barrier. The excited-state behavior of 1f resembles 1a and 1b instead of 1c-e as a consequence of the less planar amine geometry and weaker orbital interactions between the N-phenyl and the aminostilbene groups. Such an N-phenyl substituent effect is also found for 2 and 3 and thus appears to be general for stilbenoid systems. The nature of this effect can be described as an "amino conjugation effect".  相似文献   

15.
A new emissive mononuclear homoleptic Cu(I) complex of 5-tert-butyl-3-(6-methyl-2-pyridyl)-1H-1,2,4-triazole (bmptzH),[Cu(bmptzH)2](ClO4) (1), has been synthesized by treatment of [Cu(PPh3)2(CH3CN)2](ClO4) or[Cu(CH3CN)4](ClO4) with the bmptzH ligand. It is revealed that complex 1 displays a distorted N4 tetrahedral arrangement formed by two bmptzH chelates, in which bmptzH adopts a neutral bidentate chelating coordination mode using the N atom of the pyridyl ring and the 4-N not 2-N atom of the 1,2,4-triazolyl ring. It is shown that complex 1 is highly stable and exhibits good luminescence properties in solution and solid states at room temperature due to the introduction of a methyl group at the ortho-position of the pyridyl ring.  相似文献   

16.
Substituent effects are considered, and it is shown that a given substituent has effects on the activity of the-CH=N- group dependent on the benzene ring to which it is attached. An electron-donor substituent shifts El/2 towards the negative side if it is introduced into the p position of the aniline phenyl group, because a substituent in that position has two forms of conjugation: with the double-bond electrons and with the electron pair on the N atom. A substituent in the same position in the benzylidene part does not have the latter form of conjugation and does not alter the molecular geometry, so it has less effect on E1/2 for the-CH=N- group.  相似文献   

17.
Conclusions The reaction of difluoronitroacetic acid with mercuric oxide in aromatic hydrocarbons proceeds by mercuration of the aromatic ring and formation of arylmercury salts of difluoronitroacetic acid. Aryl derivatives of mercuric chloride are obtained in the case of fluorochloronitroacetic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2790–2792, December, 1985.  相似文献   

18.
从芳基二茂铁的汞化产物中首次分离出四种异环二取代产物 1-氯汞基-1'-芳基二茂铁。1-氯汞基-1'-芳基二茂铁与碘作用得到四种相应的碘代产物。氯汞基二茂铁及1-氯汞基-1'-芳基二茂铁经[ClRh(CO)~2]~2 催化偶联反应制得联二茂铁和三种1'、1''-二芳基联二茂铁。以上化合物的组成与结构经元素分析、IR 和^1H NMR确证, 其中10种为新化合物。  相似文献   

19.
Mercury-containing methylpyrylium perchlorates were synthesized by mercuration of - and -methylpyrylium perchlorates with mercuric acetate and trifluoroacetate. A mechanism is proposed for the mercuration reaction. The salts obtained undergo decomposition upon reaction with mineral acids to give the starting methylpyrylium salts, while bromomethylpyrylium perchlorates are formed upon reaction with bromine as a result of cleavage of the C-Hg bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 881–886, July, 1981.  相似文献   

20.
The (13)C and (15)N NMR chemical shifts for ring atoms of a series of N-alkylnicotinamides are shown to be correlated with their reduction potentials and reactivities toward NaBH(3)CN. The nicotinamide compounds include N-ethyl-N-benzyl-N-[p-(trifluoromethyl)benzyl]-, N-(p-cyanobenzyl)-, N-(carbomethoxymethyl)-, and N-(cyanomethyl)nicotinamides. The values of delta()13(C) for all the ring carbons increase with increasing electron-withdrawing power of the N-alkyl substituent. The value for C-4 increases the most, a range of 2.4 ppm in this series, whereas those for other atoms increase on the order of 1 ppm. The value of delta()15(N) for N-1 decreases with increasing electron-withdrawing power over a range of 20 ppm. The NMR data indicate that inductive electron withdrawal by N-alkyl substituents polarizes the pi-electron system to decrease electron density on ring carbons and increase electron density on the ring nitrogen. The values of log k (second order) for reduction of these compounds by NaBH(3)CN are proportional to the values of delta()13(C) for C-4 and inversely proportional to delta()15(N) for N-1. The reduction potentials are proportional to delta()13(C). The substituent effects are qualitatively similar to the substrate-induced electrostatic effects on the nicotinamide ring of NAD(+) at the active site of UDP-galactose 4-epimerase (Burke, J. R.; Frey, P. A. Biochemistry 1993, 32, 13220-13230). However, they differ quantitatively in that the upfield perturbation at N-1 is smaller in the enzyme and the signal for C-6 is also shifted upfield. The substrate-induced enzymatic perturbation of electron density at C-4 of NAD(+) quantitatively accounts for its increase in reactivity at the active site, but the perturbation at N-1 is less closely correlated with reactivity.  相似文献   

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