201011-40-7Relevant articles and documents
Catalysis with gold complexes immobilised on carbon nanotubes by π-π Stacking interactions: Heterogeneous catalysis versus the boomerang effect
Vriamont, Charles,Devillers, Michel,Riant, Olivier,Hermans, Sophie
, p. 12009 - 12017 (2013)
A new pyrene-tagged gold(I) complex has been synthesised and tested as a homogeneous catalyst. First, a simple 1,6-enyne was chosen as a model substrate for cyclisation by using different solvents to optimise the reaction conditions. The non-covalent immobilisation of our pyrene-tagged gold complex onto multi-walled carbon nanotubes through π-π stacking interactions was then explored to obtain a supported homogeneous catalyst. The heterogenised catalyst and its homogeneous counterpart exhibited similar activity in a range of enyne cyclisation reactions. Bearing in mind that π-π interactions are affected by temperature and solvent polarity, the reuse and robustness of the supported homogeneous catalyst was tested to explore the scope and limitations of the recyclability of this catalyst. Under the optimised conditions, recyclability was observed by using the concept of the boomerang effect. Copyright
Phosphorus functionalized dendrimers and hyperbranched polymers: Is there a need for perfect dendrimers in catalysis?
Ribaudo, Fabrizio,Van Leeuwen, Piet,Reek, Joost
experimental part, p. 79 - 98 (2010/03/03)
In this paper we describe the facile and straightforward covalent functionalization of commercially available dendritic poly(propylenimine) and hyperbranched poly(ethylenimine) with P-containing functional groups. The P-functionalized macromolecules have been applied as multivalent ligands in the Pd-catalyzed allylic substitution reactions (batch and continuous process) using either morpholine or thiophenol as nucleophile. Palladium complexes of all described molecules are active in allylic substitution reactions. The PEI functionalized polymers appear more sensitive to small changes in the P/Pd ratio than the PPI analogues, but form catalysts that are more active. When used in a continuous flow process the macromolecules are completely retained by the nanofiltration membrane, while the catalytic activity decreases with time because of palladium depletion. This is more severe for the allylic thiolation, probably because of the stronger affinity of sulfur for palladium, facilitating palladium leaching.
First fluorescent photoinduced electron transfer (PET) reagent for hydroperoxides
Onoda, Maki,Uchiyama, Seiichi,Endo, Atsushi,Tokuyama, Hidetoshi,Santa, Tomofumi,Imai, Kazuhiro
, p. 1459 - 1461 (2007/10/03)
(Matrix presented) A novel fluorescent reagent for hydroperoxides, 4-(2-diphenylphosphinoethylamino)-7-nitro-2,1,3-benzoxadiazole (1), was developed on the basis of the method for designing photoinduced electron transfer (PET) reagents having a benzofurazan skeleton. Compound 1 was quantitatively reacted with hydroperoxides to give its fluorescent derivative, 2. In acetonitrile, the Φ value (0.44) of 2 was 31 times greater than that of 1. The long excitation (458 nm) and emission (520 nm) wavelengths of 2 are suitable for the determination of hydroperoxides, especially in biosamples.
