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1.
金催化顺丁烯二酸酐的选择加氢反应   总被引:1,自引:0,他引:1  
马宇春  石峰  熊海  张庆华  邓友全 《化学学报》2004,62(13):1242-1246,J003
采用溶胶-凝胶法制备了一系列担载纳米金催化剂,用以催化顺丁烯二酸酐(简称顺酐,MA)的选择加氢反应.模板剂的引入改变了催化剂载体的结构,从而提高了其催化活性和对加氢产物丁二酸酐(SA)以及丁二酸二乙酯(DFAS)的选择性.同时考察了反应温度、溶剂、催化剂制备方法对顺酐选择加氢反应的影响以及催化剂的重复使用性能.实验结果表明,以焙烧处理除去模板剂十八胺的Au/SiO2-O(C)为催化剂时,顺酐选择加氢制取丁二酸酐和一步加氢酯化制取丁二酸二乙酯的效果最佳,其转化率以及产物选择性均大于99.5%.  相似文献   

2.
合成具有双磺酸基功能化离子液体[BS2 DABCO][HSO4]2用于甘油与叔丁醇(TBA)醚化反应中,显示出良好的催化活性.采用红外光谱和热重分析对其进行了物理表征,详细考察了反应时间、温度、催化剂用量与甘油/叔丁醇物质的量之比等因素对甘油转化率及单叔丁基甘油醚选择性的影响,得出最佳反应条件.当反应时间为6 h,温度...  相似文献   

3.
以金鸡纳碱衍生物作为手性修饰剂,研究了三苯基膦稳定的1.0%Ru+0.2%Rh/γ-Al2O3催化剂催化芳香酮多相不对称加氢,考察了修饰剂种类及浓度、碱添加剂种类及浓度、溶剂、氢气压力等因素对不对称加氢反应的影响.结果表明,金鸡纳碱衍生物对1.0%Ru+0.2%Rh/γ-Al2O3-tpp催化剂具有较好的修饰作用,在优化反应条件下苯乙酮加氢反应的对映选择性高达84%.  相似文献   

4.
《化学学报》2012,70(3)
以金鸡纳碱衍生物作为手性修饰剂,研究了三苯基膦稳定的1.0%Ru+0.2%Rh/γ-Al2O3催化剂催化芳香酮多相不对称加氢,考察了修饰剂种类及浓度、碱添加剂种类及浓度、溶剂、氢气压力等因素对不对称加氢反应的影响.结果表明,金鸡纳碱衍生物对1.0%Ru+0.2%Rh/γ-Al2O3-tpp催化剂具有较好的修饰作用,在优化反应条件下苯乙酮加氢反应的对映选择性高达84%.  相似文献   

5.
研究了钌-双膦-二胺配合物催化剂RuC1_2[(S)-P-Phos]-[(S)-DAIPEN][P-Phos:2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'.二吡啶,DA肫N:1,1.二(4.甲氧苯基).2.异丙基.1,2.乙二胺]催化芳香酮不对称加氢反应的性能,考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响.在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1,氢气压力为2 MPa,反应温度为30℃时,苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%,2'-溴苯乙醇的ee值町达97.1%.  相似文献   

6.
研究了钌-双膦-二胺配合物催化剂RuCl2[(S)-P-Phos]-[(S)-DAIPEN] [P-Phos: 2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'-二吡啶, DAIPEN: 1,1-二(4-甲氧苯基)-2-异丙基-1,2-乙二胺]催化芳香酮不对称加氢反应的性能, 考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响. 在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1, 氢气压力为2 MPa, 反应温度为30 ℃时, 苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%, 2'-溴苯乙醇的ee 值可达97.1%.  相似文献   

7.
蒋和雁 《分子催化》2013,27(2):99-106
以金鸡纳碱衍生物作为手性修饰剂,研究了三苯基膦(tpp)稳定的1.0%Ru/γ-Al2O3催化剂催化芳香酮多相不对称加氢,考察了稳定剂种类、修饰剂种类、金属负载量、溶剂、碱添加剂种类等因素对不对称加氢反应的影响.结果表明,金鸡纳碱衍生物对1.0%Ru/γ-Al2O3/2tpp催化剂具有较好的修饰作用,在优化的反应条件下苯乙酮及其衍生物加氢反应的对映选择性达78%~98%,2-乙酰基噻吩加氢反应的对映选择性可达80%,2-乙酰基呋喃加氢反应的对映选择性可达75%.  相似文献   

8.
Hβ分子筛催化的甲苯与乙酸酐(AA)酰化反应研究   总被引:3,自引:1,他引:3  
以Hβ分子筛为催化剂,对甲苯与乙酸酐(AA)的酰化反应进行了研究。通过研究反应温度、压力、甲苯与乙酸酐(AA)摩尔比、催化剂用量、以及溶剂的种类和用量等因素对反应转化率和选择性的影响,确定了较优的反应条件。结果表明,Hβ分子筛对甲苯与乙酸酐(AA)酰化反应具有较好的催化活性和选择性,适宜的反应条件为:温度130 ℃、甲苯/乙酸酐(AA)摩尔比20、催化剂/乙酸酐(AA)重量比0.8,极性溶剂如硝基苯等对酰化反应有一定的促进作用,但选择性有所下将,而非极性溶剂如二氧化碳可部分抑制催化剂的失活。  相似文献   

9.
在温和条件下制备了L-脯氨酸稳定并修饰的负载型金属铱催化剂,用于苯乙酮及其衍生物不对称催化加氢反应. 考察了L-脯氨酸的量、溶剂、碱以及碱的量和氢气压力对苯乙酮不对称催化加氢反应的影响. 结果显示,该催化剂催化苯乙酮不对称加氢反应获得了92.1%的转化率和32.9%的对映选择性(e.e.),催化2′-(三氟甲基)苯乙醇的对映选择性为39.3,这一结果高于目前报道的天然手性修饰剂修饰的负载型金属催化剂. 该催化循环使用5次, 对映选择性只有小幅度下降.  相似文献   

10.
研究了溶胶-凝胶法制备的NiO-SiO2催化剂上温度,压力,反应时间,催化剂用量等工艺条件对顺酐液相选择加氢性能的影响.结果表明镍含量为30%的NiO/SiO2气凝胶催化剂在适当的反应条件下顺酐液相加氢可高选择性地获得丁二酸酐和γ-丁内酯.当反应温度453K,氢压5.0MPa,反应时间8h,顺酐转化率100%,γ-丁内酯的选择性78.57%;生成丁二酸酐的条件因有或无溶剂而异,有溶剂存在时,反应温度398K,氢压2.0MPa;无溶剂在423K,氢压1.0MPa,顺酐转化率和丁二酸酐的选择性达99.5%以上.  相似文献   

11.
4-苯基-1-丁醇的合成研究   总被引:2,自引:0,他引:2  
4-苯基-1-丁醇是一种重要的药物中间体。文章以苯和丁二酸酐为起始原料,经付克酰基化得3-羰基苯丁酸;通过对羰基还原成亚甲基的方法进行研究,确定了通过Wollf-Kishner还原法合成苯丁酸,然后通过酯化和硼氢化钠还原酯等反应合成了4-苯基-1-丁醇,使总收率不低于35%。该合成方法避免了毒性较大的锌-汞齐,革除了价格昂贵的氢化铝锂,使之更适合于工业化生产。  相似文献   

12.
An efficient and practical procedure for the synthesis of esonarimod, (R,S)-2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (1), a new antirheumatic drug, has been developed. The intermediate, 2-methylene-4-(4-methylphenyl)-4-oxobutanoic acid (2), was prepared by Friedel-Crafts acylation of toluene with itaconic anhydride (3) in the presence of aluminum trichloride and nitrobenzene in 63% yield without silica gel column purification. Compound 1 was prepared by Michael addition of 2 with thioacetic acid (4) in 74% yield. Overall, 1 was obtained in 47% yield from 3. The structures and synthetic mechanisms of by-products (five compounds) of 2 were also clarified.  相似文献   

13.
赵振华 《分子催化》2004,18(3):161-166
一种新的催化剂,SnCl2·2H2O,已用于2,3-二甲基-2-丁烯与乙酐的酰化反应来制备高产率的3,3,4-三甲基-4-戊烯-2-酮 (TMP). 发现SnCl2·2H2O是室温下2,3-二甲基-2-丁烯与乙酐进行酰化反应的有效催化剂. 考察了催化剂用量、乙酐用量、反应时间和溶剂的加入等因素对该酰化反应的影响. 发现当催化剂/2,3-二甲基-2-丁烯摩尔比在0.30/1和 0.60/1之间、反应时间为2 h时,所得酰化产品的产率最高. 该酰化反应进行到完全所需的时间取决于催化剂用量和乙酐用量. 在需要加入溶剂的情况下,二氯甲烷或氯仿是一种合适的溶剂.  相似文献   

14.
The reaction of anthranilic acid hydrazide with diethyl oxalate under microwave irradiation was accompanied by decarboxylation with formation of 3-amino-3,4-dihydroquinazolin-4-one, and acylation of the latter with succinic anhydride gave N-(4-oxo-3,4-dihydroquinazolin-3-yl)siccinimide which was converted into various N-(4-oxo-3,4-dihydroquinazolin-3-yl)succinamic acid derivatives.  相似文献   

15.
4-Trifluoroacetamidobenzotriazole (I) was synthesized by acylation of 4-aminobenzotriazole with trifluoroacetic anhydride under mild conditions in pyridine. The silver salt (II) of I was obtained by treatment of base I with an aqueous alcohol solution of AgNO3. Condensation of silver salt II with 1-bromo-2,3,4-tri-O-acetyl-D-ribopyranoside leads to 4-trifluoroacetamidobenzotriazole N2-2,3,4-tri-O-acetyl--D-ribopyranoside (III). The structure of nucleoside III was confirmed by its IR, UV, and PMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1691–1692, December, 1978.  相似文献   

16.
The nitrosation of N-aryl-3-oxobutanethioamides afforded 1-(6-R-benzothiasol-2-yl)-1-hydroxyimino-2-propanones that at oximation with hydroxylamine were converted into 1-(6-R-benzothiazol-2-yl)-1,2-dihydroxyiminopropanes. The latter were dehydrated by heating with succinic anhydride at 140°C yielding therewith 3-(6-R-benzothiazol-2-yl)-4-methyl-1,2,5-oxadiazoles.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 759–761.Original Russian Text Copyright © 2005 by Britsun, Borisevich, Samoilenko, Lozinskii.  相似文献   

17.
A facile procedure was described for the hapten design of the N-methylcarbamate insecticide propoxur.Two new haptens of propoxur(hapten 1a and hapten 1b) were synthesized by introducing appropriate spacers in the pesticide aromatic moiety of the analyte molecular structure.First,the propoxur reacted with nitric acid to yield the intermediate product.Then hapten 1a was prepared via the reduction of the intermediate product,and hapten 1b was formed by the acylation of hapten 1a with succinic anhydride.In addi...  相似文献   

18.
Acylation of 1-ethyl-3-(N,N-dimethyl)aminomethylene-1,2-dihydro-2-indolinone by succinic anhydride in the presence of aluminum chloride has been studied. PMR spectroscopy shows that this acylation leads to formation of a mixture of the 5- and 6-succinoyl derivatives with predominance of the latter (cis and trans isomers of both these products were found). The reaction of the latter with hydrazine hydrate gives hydrazinomethylene derivative of 2-indolinone, in reaction of which with various carbonyl compounds a series of oxindol hydrazones has been obtained. The reaction of these products with primary amines smoothly leads to transamination and the formation of enamines of 1,6-disubstituted 2-indolinone. NIOPIK Russian Federation State Science Center, 103787 Moscow, Russia and TsKhLS-VNIKhFI, 119815 Moscow, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1347–1355, October, 1999.  相似文献   

19.
赵振华 《分子催化》2002,16(2):121-126
在H3PO4存在下进行了2,3-二甲基-2-丁烯与乙酐的酰化反应,结果表明,H3PO4是室温下催化2,3-二甲基-2-丁烯与乙酐酰化反应的有效催化剂,在H3PO4存在下,酰化产物的收率主要取决于:(a)H3PO4的用量,(b)乙酐的用量;(c)反应温度和(d)反应时间,在适宜反应条件下,所得3,3,4-三甲基-4-戊烯-2-酮(TMP)约为99%,另外还发现,反应体系中加入少量乙酸,不会明显减少酰化产物的收率,乙酐的纯度,反应物的加入顺序对该反应几乎没有任何影响,在有和没有溶剂CH2Cl2的条件下所得酰化产物的收率是可比的。  相似文献   

20.
Poly(ethylene glycol) (PEG) triblock and diblock amphiphilic block copolymers were synthesized from poly(ethylene glycol) and poly(ethylene glycol) monomethyl ether, respectively. The hydroxyl groups of PEG readily react with 2-(1-octadecenyl) succinic anhydride (OSA) at 140 °C through ring-opening reaction of the succinic anhydride. Both the PEG-OSA diblock and triblock copolymers are produced without use of any solvent or catalyst. The molecular structure of the copolymers was characterized by 1H NMR and FTIR spectroscopy, and the thermal properties by DSC. The behavior of the copolymers in selective and nonselective solvents was studied by 1H NMR spectroscopy in deuterium oxide and d-chloroform. The aggregation of the polymers in water was studied with a particle size analyzer and a transmission electron microscope (TEM) in bright field mode. The results show that the hydrophobic C18 chain with intramolecular succinic anhydride linker can be attached to the hydrophilic PEG chain, an ester bond forming between the blocks. The copolymers exhibit flexible, liquid-like hydrophobic blocks even in water, which is a nonsolvent for OSA. PEG-OSA block copolymers self-organize in water, forming micellar polymer aggregates in nanoscale.  相似文献   

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