Heteropolyacid salts as self-separation and recyclable catalysts for transesterification of trimethylolpropane
摘要:
A series of heteropolyacid (HPA) salts as catalysts were prepared and characterized. Transesterifications of trimethylolpropane (TMP) were carried out using these catalysts. The influence of organic cations and heteropolyanions on the reaction, optimization of reaction conditions, and catalytic reusability were investigated. The results show that the heteropolyacid (HPA) salts present a self-separation performance after reaction, which can be easily recovered and quite steadily reused as demonstrated by a eight-run recycling test. Moreover, the pyridinium with PW12O403- as the anion ([PyBS](3)PW12O40) showed the best catalytic performance among the heteropolyacid salts for the transesterification of trimethylolpropane with various methyl esters. (C) 2010 Elsevier B.V. All rights reserved.
Ir/C and Brφnsted acid functionalized ionic liquids: an efficient catalytic system for hydrogenation of nitrobenzene to p-aminophenol
作者:Hong Wang、Taotao Jiang、Lei Ma、Hanbing Wang、Xiaoliang Xu、Chunshan Lu、Xiaonian Li
DOI:10.1039/c7ra04722c
日期:——
and Brφnsted acidfunctionalizedionicliquid was applied, for the first time, to the one-pot hydrogenation of nitrobenzene to p-aminophenol. Our results indicate that the PAP selectivity of Ir/C and [SO3H-bmim][HSO4] Brφnsted functionalizedionicliquid was far more than that of the traditional Pt/C and sulfuric acidcatalyst system. Furthermore, the dually functionalizedionicliquid ([HSO3-b-N-Bu3][HSO4])
Selective monoalkylation of hydroquinone in the presence of SO3H-functionalized ionic liquids as catalysts
作者:Priyanka V. Bhongale、Sunil S. Joshi、Nilesh A. Mali
DOI:10.1007/s11696-020-01230-1
日期:2020.12
A process aiming at O -alkylation of hydroquinone (HQ), where ionic liquids (ILs) act as catalyst is objectively described. Five SO3H-functionalized ILs having different cations were prepared and characterized by NMR and FTIR techniques. The acidity and thermal stability of ILs were determined by Hammett function and thermogravimetric analysis (TGA), respectively. The catalytic activity of these ILs
瞄准的方法 Ô 烷基化氢醌(HQ),其中离子液体(离子液体)作为催化剂客观描述。制备了五种具有不同阳离子的SO 3 H官能化IL,并通过NMR和FTIR技术对其进行了表征。IL的酸度和热稳定性分别通过Hammett函数和热重分析(TGA)确定。测试了这些IL的催化活性以测定 O 在少量苯醌(BQ)存在下,用甲醇在4-甲氧基苯酚(4MP)中对HQ进行烷基化。使用1,3-二磺酸咪唑硫酸氢盐(IL2)催化剂检查并优化了反应参数(如温度,时间,催化剂负载和底物浓度)对HQ转化率和产物分布的影响,以使4MP的收率最大化。在338 K温度,5.45×10 –2 mol HQ,8.33×10 –3的条件下,所需产物4MP的最大产率为93.79% 摩尔BQ和120分钟反应时间内的催化剂负载量为10.37摩尔%。在高达338 K的温度下观察到单一产物的形成,但较高的温度(338 K以上)和更长的反应时间导致形成副产物2
PALLADIUM CATALYST SYSTEM COMPRISING ZWITTERION AND/OR ACID-FUNCTIONALYZED IONIC LIQUID
申请人:Riisager Anders
公开号:US20110065950A1
公开(公告)日:2011-03-17
The present invention concerns a catalyst system in particular a catalyst system comprising Palladium (Pd), a zwitterion and/or an acid-functionalized ionic liquid, and one or more phosphine ligands, wherein the Pd catalyst can be provided by a complex precursor, such as Pd(CH
3
COO)
2
, PdCl
2
, Pd(CH
3
COCHCOCH
3
), Pd(CF
3
COO)
2
, Pd(PPh
3
)
4
or Pd
2
(dibenzylideneacetone)
3
. Such catalyst systems can be used for e.g. alkoxycarbonylation reactions, carboxylation reactions, and/or in a co-polymerization reaction, e.g. in the production of methyl propionate and/or propanoic acid, optionally in processes forming methyl methacrylate and/or methacrylic acid. Catalyst systems according to the invention are suitable for reactions forming separable product and catalyst phases and supported ionic liquid phase SILP applications.
Brønsted acid ionic liquid catalyzed formation of pyruvaldehyde dimethylacetal from triose sugars
作者:Shunmugavel Saravanamurugan、Anders Riisager
DOI:10.1016/j.cattod.2012.07.001
日期:2013.2
A series of sulfonic acid functionalized ionic liquids (SO3H-ILs) have been synthesized, characterized and investigated as catalysts for the conversion of the triose sugars, 1,3-dihydroxyacetone (DHA) and glyceraldehyde (GLA), to pyruvaldehyde dimethylacetal (PADA) in methanol. Depending on the reaction conditions and the applied SO3H-ILs a good yield of up to 52% of PADA was obtained. Under identical