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1.
离子液体[Bmim]BF4/水混合溶剂中的1-丁烯氢甲酰化反应研究   总被引:2,自引:0,他引:2  
以水溶性离子液体[Bmim]BF4和水作为混合溶剂、RhCl3/TPPTS为催化剂进行1-丁烯氢甲酰化反应.产物可方便地通过重力沉降分离,戊醛的正-异比达9.1:1(V:V)催化体系经5次循环,催化活性未见明显降低.  相似文献   

2.
高效液相色谱法测定生姜中的6-姜酚   总被引:7,自引:0,他引:7  
用C18色谱柱,以V(甲醇):V(水):V(冰乙酸)=35:64:1溶液作流动相,进样量5μL,在流速1.0mL/min下,可不经分离直接测定生姜中的6-姜酚。方法RSD小于1.00%,回收率97%~102%,相关系数0.9999。  相似文献   

3.
王俏 《合成化学》2004,12(2):204-206
研究了以麦秆为原料用水解-氧化-水解法制取草酸的工艺方法。最佳反应条件:麦秆用量50g,硫酸浓度70%,物料浸泡时间≥3h,m(硝酸):m(麦秆)=2.1:1.0;氧化催化剂V2O5-FeCl3[n(V2O5):n(FeCl3)=1:1]用量0.1g,氧化-水解反应时间5h,反应温度65℃~70℃,草酸二水合物收率75.5%。  相似文献   

4.
合成了新荧光试剂2,3,4-三羟基苯乙酮缩-2-羧基苯胺(TAFA)。详细研究了试剂与铜的荧光反应新体系的最佳适宜条件。在pH9.0的乙醇/水(3.5:6.5,V/V)溶液中,该试剂与铜离子形成稳定的络合物,组成比为1:1(金属:试剂),λex/em=422.4/561.6nm。所建立的铜的荧光分析方法的线性范围为0.5~120.0μg/L;检出限为0.26μg/L。方法成功地应用于矿泉水和水中痕量铜的测定。  相似文献   

5.
以3-氨基吡嗪-2-羧酸为原料,经酯化反应、亲电反应和重氮化反应合成了3-氟-6-碘吡嗪-2-羧酸甲酯(1),总收率62.34%,其结构经1H NMR、13C NMR和MS确证,用X-单晶衍射法测定了化合物的晶体结构。结果表明:1(CCDC: 1986368)属单斜晶系,空间群C2/c,晶胞参数a=17.6566(5) Å, b=4.74850(10) Å,c=19.6368(6) Å,β=95.6540(10)°,V=1638.39(8) Å3,Z=8,Rgt(F)=0.0173,wRref(F2)=0.0465,F(000)=1056,μ=3.885 mm-1  相似文献   

6.
1-(4-乙酰氨基苯基)-α-溴代-1-丙酮(I)是合成强心药物匹莫苯(Pirnobendan)和新型抗抑郁类药物氨基酮的主要中间体,它可以1-(4-乙酰氨基苯基)丙酮(Ⅱ)为原料,通过α位溴代得到。主要方法有:(1)以冰醋酸作溶剂,滴加溴的醋酸溶液反应后,经氯仿萃取,硅胶G柱层析分离得产品。  相似文献   

7.
新型药物辅料2-羟丙基-β-环糊精的色谱分离纯化   总被引:1,自引:2,他引:1  
张毅民  张志飞  周琴  王拓 《分析化学》2006,34(5):713-716
利用薄层色谱方法对碱浓度为1.5%、β-环糊精∶环氧丙烷(摩尔比)=1∶21的条件下生成的2-羟丙基-β-环糊精进行了定性分析,并通过对展开剂的选择和优化,得到了3种能有效分离不同取代度2-羟丙基-β-环糊精的展开剂体系,分别为正丙醇-水-浓氨水(6∶3∶1,V/V),异丙醇-水-浓氨水(6∶4∶0.5,V/V)和乙醇-水-浓氨水(6∶3∶0.8,V/V)。通过以乙醇体系为洗脱剂的硅胶柱色谱对其进行分离纯化,得到了两种不同取代的2-羟丙基-β-环糊精。经过ESI-MS谱图分析,确定分离后产品分别为单取代和双取代2-羟丙基-β-环糊精。  相似文献   

8.
水杨醛缩7-氨基-8-羟基喹啉-5-磺酸(简称S7N8Q5S)在酸性介质中分解,产物呈现荧光,V(V)对该反应具有催化作用,本文建立了催化荧光法测定痕量钒的新方法。体系在PH=2的柠檬酸钠-盐酸缓冲溶液中,λex/λem=342/499(nm)。测定V(V)的最佳反应条件为0.04%S7NSQ5S5.0mL,5%KBrO35.0mL,缓冲溶液5.0mL,90℃加热5min。V(V)含量在12.0~40.0μg/L的范围内有良好的线性。将该方法用于钒铬钢样品及水样中痕量钒的测定,结果满意。本文还详细探讨了反应机理。  相似文献   

9.
本文研究了愈创木基丙三醇-β-愈创木基醚-[α-13C]的合成新路线,首次合成出α位带13C同位素标记的愈创木基丙三醇-β-愈创木基醚-[α-13C],并利用1H-NMR、13C-NMR等手段对其化学结构进行了分析。研究结果表明:利用乙醇作为反应溶剂使4-乙酰基愈创木酚-[α-13C]的溴代反应成为均相反应,溴代产物的产率可提高到90%以上。采用硅胶层析用乙酸乙酯和正己烷(1/2=V/V)做流动相可以分离得到该中间产物。通过利用过量愈创木酚和4-(α-溴代乙酰基)-愈创木酚-[α-13C]进行反应,可以得到β-0-4型木素模型化合物———愈创木基丙三醇-β-愈创木基醚-[α-13C]。  相似文献   

10.
本文研究了新显色剂8-(2-羟基-3,5-二硝基苯偶氮)-1,2,4-氨基羟基萘磺酸的合成及其光度法测定钒的条件。在0.4~1.2mol/L盐酸介质中,显色剂与钒(V)形成黄色络合物,其络合比为V(V):R=1:3。摩尔吸光系数为1.4×10~4L·mol~(-1)·cm~(1-)。可在掩蔽剂作用下,不经分离直接测定矿样中的钒。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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