Bifunctional One-Component Catalysts for the Addition of Carbon Dioxide to Epoxides
作者:Hendrik Büttner、Kornelia Lau、Anke Spannenberg、Thomas Werner
DOI:10.1002/cctc.201402816
日期:2015.2
Several bifunctional ammonium salts were synthesized and employed as one‐component catalysts for the conversion of CO2 and epoxides to produce cyclic carbonates. These catalysts show superior activities compared to their monofunctional analogs. A turnover number of up to 693 and a turnover frequency of up 392 h−1 could be achieved for the best catalyst. Moreover, the effect of various solvents has
合成了几种双功能铵盐,并将其用作单组分催化剂,用于将CO 2和环氧化物转化为环状碳酸酯。与它们的单官能类似物相比,这些催化剂显示出优异的活性。周转次数最多为693,周转频率最多为392 h -1可以达到最佳催化剂的效果。此外,已经研究了各种溶剂的作用。所有使用的溶剂和形成的产物对底物转化率都有负面影响。对于两种常规反应方案,分别在45和90°C下仔细研究了反应的范围和限制。在超过20个示例中,过滤后的分离产率为90%。此外,我们提出了环己烯基天然存在的环状碳酸酯的首次有机催化合成,其分子结构由XRD确定。此外,我们证明了该反应甚至可以在数克范围内进行,并且可以通过原位FTIR光谱进行监测。
Catalytic coupling of epoxides and CO2 to cyclic carbonates by carbon nanotube-supported quaternary ammonium salts
Quaternary ammonium chlorides bound to multi-walled carbon nanotubes as a catalyst for coupling of CO2 and epoxides to produce cyclic carbonates were explored. Reaction variables such as the epoxide structure, the length of alkyl substituents in the quaternary ammoniumsalts and the spacer chain on the catalytic performance were discussed. The yield of the cyclic carbonates varied between 7 and 89%
探索了结合到多壁碳纳米管上的季铵氯化物,作为CO 2和环氧化物偶联生成环状碳酸酯的催化剂。讨论了环氧化物结构,季铵盐中烷基取代基的长度和间隔链等反应变量对催化性能的影响。在110°C低压(2 MPa CO 2)下放置6 h后,环状碳酸酯的收率在7%至89%之间变化。环氧化物:催化剂的质量比为20–30,而1 mmol g -1季盐被接枝在碳纳米管上。发现了接枝到碳纳米管上的羧基部分和铵部分之间的协同作用,并且观察到用于接枝季铵盐的间隔基团的长度对纳米管的强烈影响。使用短(2个碳原子)和长(10个原子)间隔基可获得最佳性能,而中等大小的间隔基(6个原子)不合适。铵盐(头基)的取代基的烷基链长度影响较小,其中乙基和甲基的性能优于丁基。环氧化物的反应性如下:表氯醇>环氧丙烷>氧化苯乙烯。观察通过Brønsted' 纳米管表面上的S位在环氧化物的羧化过程中起重要作用。如果在两次试验之间适当干燥,则
Cavitand templated catalysis of acetylcholine
作者:Felix H. Zelder、Julius Rebek Jr.
DOI:10.1039/b515558d
日期:——
A Zn-salen-modified cavitand templates the catalytic formation of acetylcholine from choline and acetic anhydride.
Zn-salen修饰的cavitand模板可从胆碱和乙酸酐催化形成乙酰胆碱。
Lanthanide-Based Organic Salts: Synthesis, Characterization, and Cytotoxicity Studies
作者:Andreia Forte、Sandra Gago、Celso Alves、Joana Silva、Joana Alves、Rui Pedrosa、César A. T. Laia、Isabel M. Marrucho、Luis C. Branco
DOI:10.3390/molecules28207152
日期:——
The formulation of magnetic ionic liquids (MILs) or organicsalts based on lanthanides as anions has been explored. In this work, a set of choline-family-based salts, and two other, different cation families, were combined with Gadolinium(III) and Terbium(III) anions. Synthetic methodologies were previously optimized, and all organicsalts were obtained as solids with melting temperatures higher than
Verfahren zur Herstellung von Aminothiophenderivaten
申请人:BASF Aktiengesellschaft
公开号:EP0258855A2
公开(公告)日:1988-03-09
Verfahren zur Herstellung von Aminothiophenderivaten der Formel I
in der
R gegebenenfalls substituiertes C₁-C₈-Alkoxycarbonyl, gegebenenfalls substituiertes Carbamoyl oder Cyano bedeutet, wobei man Verbindungen der Formel II
NC-CH₂-R (II),
in der R die obengenannte Bedeutung besitzt, in Wasser mit einer Base und gleichzeitig oder anschließend mit einem Halogenacetylhalogenid umsetzt und danach mit Schwefelwasserstoff oder einem wasserlöslichen Sulfid reagieren läßt.
一种制备式 I 氨基噻吩衍生物的工艺
其中
R 是任选取代的 C₁-C₈-烷氧基羰基、任选取代的氨基甲酰基或氰基,其中式 II 的化合物
NC-CH₂-R (II)、
其中 R 具有上述含义,在水中与碱反应,同时或随后与卤乙酰卤反应,然后与硫化氢或水溶性硫化物反应。