14867-28-8Relevant articles and documents
Ionic nanoparticle networks as solid state catalysts
Roeser, Jerome,Kronstein, Martin,Litschauer, Marco,Thomas, Arne,Neouze, Marie-Alexandra
, p. 5305 - 5311 (2012)
We report on the catalytic activity for the cycloaddition of CO2 to cyclic organic carbonates of recently developed ionic nanoparticle networks (INN). The combination of high imidazolium content and ability to coordinate to CO2 molecules within the 3D network makes the hybrid INN materials highly promising heterogeneous catalysts for CO2 activation reactions. The catalytic activity of INN powders and gels was investigated with various starting epoxides. Quantitative conversion was reached with epichlorohydrin. The influence of mono or bis(imidazolium) bridging ligands and methylation at the C2 position in the aromatic ring of the organic cation could be highlighted by evaluation of the activity with the less reactive propylene oxide as the starting epoxide. Finally, the influence of the type of inorganic nanoparticle support was also studied by preparing heterobimetallic silica-zinc oxide nanoparticle networks. Promising results were obtained with various epoxides. Conversion or selectivity up to 100 % could be obtained. The catalyst could be reused owing to the good thermal stability of the hybrid inorganic-organic INN. After four reaction runs the catalyst still proved to be active. The catalytic activity of imidazolium-based nanoparticle networks was demonstrated for CO2 cycloaddition reactions to various epoxides. The hybrid solid-state material can be easily separated and reused after the reaction. Conversion or selectivity up to 100 % could be obtained under mild conditions and in a short reaction time. Copyright
Insoluble ligands and their applications. IV. Polysiloxane-bis(2-aminoethyl)amine ligands and some derivatives
Ahmed, I.,Parish, R.V.
, p. 23 - 28 (1993)
Methods have been developed for the preparation of insoluble polysiloxane ligands containing pendant - N(CH2CH2NH2)2 groups and their salicylaldimine Schiff-base and cyclised derivatives.The ability of these materials to take up metal ions from aqueous so
Nanoparticles connected through an ionic liquid-like network
Litschauer, Marco,Neouze, Marie-Alexandra
, p. 640 - 646 (2008)
Silica nanoparticles linked through ionic liquid-like molecules are synthesized by two routes. The first approach utilized a bis(trialkoxysilyl)- substituted imidazolium iodide to link the silica nanoparticles. In the second approach, the silica nanoparticles were first modified by 3- chloropropyltrimethoxysilane and N-(3-trimethoxysilylpropyl)imidazole and then coupled through nucleophilic substitution. A comparison of both approaches shows that the second approach results in a more efficient interfacing of nanoparticles. The Royal Society of Chemistry 2008.
Sustainable parts-per-million level catalysis with FeIII: One-pot cascade synthesis of 2,3-dihydroquinazolin-4(1H)-ones in water
Dutta, Apurba,Trivedi, Priyanka,Kulshrestha, Akshay,Kumar, Arvind,Chaturvedi, Vinita,Sarma, Diganta
, (2020/12/13)
A silica-supported iron complex has been identified as a highly active and reusable catalyst for the synthesis of medicinally important 2,3-dihydroquinazolin-4(1H)-ones. The catalyst was fully characterized by various spectroscopic analyses such as Fourie
Recyclable and eco-friendly Pd-complexed graphene oxide/N-heterocyclic carbene catalyst for various coupling reactions in aqueous phase
Kim, Seongsoo,Cho, Hong-Jun,Shin, Dong-Sik,Lee, Sang-Myung
supporting information, p. 2421 - 2425 (2017/05/31)
In this study, we report recyclable Pd-complexed graphene oxide (GO) catalysts with a bulky N-heterocyclic carbene (NHC) ligand (GO/NHC-Pd) for various cross-coupling reactions in the aqueous phase. To prepare GO/NHC-Pd, the NHC precursor and a trimethoxy-silane linker were combined on the GO surface via condensation, followed by the Pd chelation over GO/NHC. The GO-based catalysts were applied to three types of C–C cross-coupling reactions including Suzuki, Heck and Sonogashira reactions in the aqueous phase, to evaluate their catalytic performance. The reusability of the catalysts was tested by performing five consequent cross-coupling reactions.
Temperature-dependent immobilization of a tungsten peroxo complex that catalyzes the hydroxymethoxylation of olefins
Chen, Jizhong,Hua, Li,Chen, Chen,Guo, Li,Zhang, Ran,Chen, Angjun,Xiu, Yuhe,Liu, Xuerui,Hou, Zhenshan
, p. 1029 - 1037 (2015/06/08)
Abstract A tungsten peroxo complex stabilized by the bidentate picolinato ligand has been synthesized and then immobilized successfully on imidazole-functionalized silica. The immobilized tungsten-based catalyst was employed as an efficient catalyst for the one-pot synthesis of β-alkoxy alcohols from olefins and methanol with H2O2. Regarding the catalyst evaluation and the results of characterization by the various methods, it was demonstrated that the immobilization of tungsten peroxo complex was highly temperature-dependent. The tungsten peroxo complex can dissociate and diffuse into the liquid phase at reaction temperature, resulting in a homogeneous reaction. Nevertheless, the catalytically active species was anchored on the imidazole-functionalized silica by hydrogen bonding as the temperature was lowered to 0°C after the reaction, which thus offered a highly effective approach for recycling the catalyst for consecutive cycles. In addition, various olefins can be converted to the corresponding β-alkoxy alcohols with good conversion and selectivity under relative mild conditions by H2O2. Running hot and cold: A tungsten peroxo complex (see picture) can dissociate and diffuse into the liquid phase at the reaction temperature, resulting in a homogeneous reaction. After reaction, the catalytically active species was anchored on the functionalized silica by hydrogen-bonding as the temperature was lowered to 0°C. This offers an effective approach for catalyst recovery and recycling.