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1.
1 INTRODUCTION Inorganic solid supports as catalysts resulting in higher selectivity, milder conditions and easier work-up have been reported as useful catalysts for many reactions [1~3]. Recently, we have reported the Knoevenagel condensation catalyzed by KF-Al2O3[4]. In this paper, we discussed the crystal structure of the title compound synthesized by the reaction of salicylaldehyde and ethyl cyanoacetate in DMF using the catalyst KF-Al2O3 at room temperature KF-Al2O3. In or…  相似文献   

2.
One-pot reaction of aldehydes,α-haloketones and (phenylsulfonyl) acetonitrible promotes by SmI3 proceeded smoothyl to give 1-cyano-1-phenylsulfonyl-2-aryl-3-aroyl-propane derivatives in moderate good yields.  相似文献   

3.
The intermolecular reductive coupling cyclization reaction of 1,1-dicyanoalkenes promoted by Sm^0/cat.HgCl2 studied.A possible reaction mechanism was proposed.  相似文献   

4.
The novel complex [K(18-C-6)]2[Cd(mnt)2][18-C-6-18-crown-6,nmt=1,2-dicyanoethene-1,2-dithiolate,C2S2-(CN)2^2-] was synthesized and characterized by elemental analysis,IR spectrum and X-ray diffraction analysis.The complex displays two-dimensional network structure of [K(18-C-6)] complex segments and [Cd(nmt)2] complex segment bridged by S-K-S,S-K-N and N-K-N interactions between adjacent[K(18-C-6)] and [Cd(mnt)2]units.  相似文献   

5.
2—氰基—4—硝基苯胺的薄层色谱—紫外分析   总被引:1,自引:0,他引:1  
  相似文献   

6.
α-Oxoketene dithioacetals 2 via, 1,2-nucleophilic addition by allyl magnesium bromide afforded corresponding alcohols (3).Treated with water and catalyzed by Lewis acid, the alcohols 3 were converted regiospecifically to the conjugated 1,1—dialkylthio—1,3,5 hexatrienes (4). Both the alcohol 8 and its methoxy methyl ether 9 were sensative to dilute sulfuric acid and cyclized under this condition to form the aryl methylthio ether (10).  相似文献   

7.
张华廖志新  岳建民 《中国化学》2004,22(10):1200-1203
Four cyano-containing compounds, (1E,4α,5β,6α)-4,5,6-trihydroxy-2-cyclohexen-l-ylideneacetonitrile (1), lithospermoside (2), 4-hydroxy-2-β-D-glucopyranosyl oxyphenylacetonitrile (3) and 4-[β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranosyl oxy]phenylacetonitrile (4), and a nitro-containing one, 4-[β-D-xylopyranosyl-(1→6)-O-β-D-glucopyranosyloxy]-1-(2-nitroethyl)benzene (5), as well as eleven other types of compounds, were isolated from the roots of Semiaquilegia adoxoides. Their structures were elucidated mainly by spectroscopic methods. Among them, 1 and 4 are new isolated compounds. The cyano- and nitro-containing compounds are very rare in plants and their isolation from one traditional Chinese medicine is really interesting.  相似文献   

8.
聂晶晶  吴景云 《结构化学》2001,20(6):470-472
1 INTRODUCTION The enantiomers separated by a co- crystallization method using an appropriate chiral as separating reagent has attracted many attentions in the past years[1]. Recently we are interested in enantiomeric discrimination by chiral amino acid. When racemic D,L-tartaric acid was tried to be separated by the L-glutamine in a hot aqueous solution, the well shaped crystals were obtained. The determination of melting point (220℃) and density (1.66 g穋m-3) showed it is…  相似文献   

9.
2—氰基—4—硝基苯胺的薄层色谱紫外光度分析   总被引:1,自引:0,他引:1  
本文应用薄层色谱紫外光度法,测定了产品的主要成分2-氰基-4-硝基苯胺和杂质,得到了满意的分析结果。与经典化学法比较,这种方法具有简单、快速、精确的特点。回收率99%-101%,相对标准偏差0.7%-1.1%,2-氰基-4-硝基苯胺含量在0-135μg/25mL范围内遵守比耳定律。  相似文献   

10.
贾志胜  张斌 《结构化学》1995,14(5):408-411
用X射线晶体结构分析法测定和分析了dl-2,3-二氰基-2,3-二(3,4-二甲氧基苯基)丁二酸二乙酯的分子结构和晶体结构。晶体学数据为:C26H28N2O8,Mr=496.52,空间群P1,a=12.047(1),b=13.271(1),c=8.728(2)A,a=90.71(1),β=108.81(1),γ=84.87(1)°,V=1315.4(2)A^3,Z=2,Dc=1.254g/cm^3  相似文献   

11.
ICP-AES法测定铝中铁、硅、铜、镓、镁、锌、锰和钛   总被引:9,自引:0,他引:9  
用 50g L氢氧化钠溶液溶解铝样品 ,硝酸 (1 1 )酸化 ,以ICP AES测定其中铁、硅、铜、镓、镁、锌、锰和钛等 8种杂质元素。  相似文献   

12.
标题化合物C24H30O5是由邻甲氧基苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单斜晶系,空间群C2/c,a=33.942(6),b=7273(1),c=22667(4)A,β=128.989(9)°,Mr=398.50,V=4349(1)A3,Dc=1.2179·cm-3,Z=8,μ(MoKa)=840mm-1,F(000)=1712。晶体结构用直接法解出,经用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.043,Rw=0.052。在晶体结构中,存在一个分子间氢键。  相似文献   

13.
标题化合物C23H25对O3Cl是由邻氯苯甲醛与5,5-二甲基1,3-环己二酮在N,N-二甲基甲酸腹中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单科晶系,空间群=1632。晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.054,Rw一0.063。在晶体结构中,吡喃环与苯环之间的两面角为92.43°。  相似文献   

14.
标题化合物C24H29NO4?1/2C2H5OH稨2O)由香兰素、5,5-二甲基-1,3-环己二酮、醋酸铵在微波辐射下干反应并经95%乙醇重结晶而得C24H29NO4穀2(C2H5OH稨2O)晶体。结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/n, a = 9.810(2), b = 14.516(3), c = 17.008(3) ? b = 101.03(2), V = 2377.2(8) ?, Z = 4, Mr = 427.52, Dc = 1.195 g/cm3 , m(MoKa) = 0.082 mm-1, F(000) = 920。晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R = 0.0406, wR = 0.0892。X-射线衍射分析结果表明,吡啶环和与之稠合的2个六员环均为信封式构象。  相似文献   

15.
陈茹玉  程磊峰 《化学学报》1990,48(7):726-730
本文报道了七个新的2,4,5-三氧-1,3,2,4-二氮二磷杂环戊烷衍生物的制备, 产物的结构经IR, ^1H和^31P NMR, MS以及元素分析证实, 并利用^31P NMR和GC-MS区分了化合物的顺式和反式异构体。  相似文献   

16.
微波消解-ICP-AES法测定氧化铝中杂质元素   总被引:2,自引:0,他引:2  
采用微波消解法,将样品用磷酸溶解,用ICP-AES测定氧化铝中Na、K、Ca、Si、Fe、Ti、Mn、Zn、Cu、V、Cr和B等12种杂质元素,采用测定标样、加标回收试验和精密度试验证明该方法简便快速,准确可靠。  相似文献   

17.
Monodisperse polyacrolien (PA) microspheres were obtained by a single step process via two mechanisms: (a) aqueous polymerization of acrolein under alkaline conditions and (b) aqueous radical polymerization of acrolein by irradiation with a cobalt source. The diameter of the former microspheres can be varied from 0.04 up to 8 μm. The monodispersity of the system is also discussed. The diameter of the latter microspheres can be varied up to 0.2 μm. Hybrido PA microspheres were formed by grafting PA microspheres of average diameter of 0.1 μm obtained by irradiation onto the surface of PA microspheres produced by the alkaline mechanism. The aldehyde content of the microspheres prepared by irradiation is much higher than those of the microspheres formed under alkaline conditions. The aldehyde groups were used for the covalent binding of ligands containing primary amino groups, such as proteins and drugs, in a single step under physiological pH.  相似文献   

18.
Layers containing oxygen compounds of copper and nickel and(or) of one of transition metals (manganese, cobalt, iron) were formed on an aluminum alloy by the plasma-electrolytic oxidation method. The layers were characterized by means of X-ray phase analysis, X-ray fluorescence microanalysis, and scanning electron microscopy and tested in the reaction of CO oxidation to CO2.  相似文献   

19.
用硝酸-高氯酸体系消解螺蛳和水葫芦样品,采用火焰原子吸收光谱法测定铜、锌、镍、铬,用石墨炉原子吸收光谱法测定铅、镉。铜、锌、镍、铬、铅、镉的检出限分别为0.328、0.126、0.271、0.416、0.006 64、0.001 15 mg/kg,线性相关系数不小于0.999 0,测定结果的相对标准偏差为1.1%~3.7%,加标回收率为86.0%~94.2%。  相似文献   

20.
锰矿石样品用HNO3-HF-HClO4酸溶除硅后,对采用ICP-AES法测定其中的铁、铝、钛、钙、镁、磷时,同时测定钡、铅的相关条件进行了试验。主要对酸溶样能否分解重晶石或天青石等含钡矿物进行了探讨,测定了3个国家级标准样品。测定结果与标准值吻合。用标准加入法测得的钡和铅的回收率分别为96.0%-100.5%,97.1%~100.0%。用该法对含钡量较高的澳大利亚锰矿进行分析,测定结果的相对标准偏差为0-82%,并将测定结果与X荧光光谱法测定结果进行了比对。  相似文献   

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