A new method for catalyst deposition on the inner walls of capillary microreactors is proposed which allows exact control of the coating thickness, pore size of the support, metal particle size, and metal loading. The wall-coated microreactors have been tested in a selective hydrogenation reaction. Activity and selectivity reach values close to those obtained with a homogeneous Pd catalyst. The...

A homogeneous Pd(II) catalyst, utilizing a simple and inexpensive amine ligand (TMEDA), allows 2-alkynoates to be prepared in high yields by an oxidative carbonylation of terminal alkynes and alcohols. The catalyst system overcomes many of the limitations of previous palladium carbonylation catalysts. It has an increased substrate scope, avoids large excesses of alcohol substrate and uses a des...

in this work, different ethyl 2,4-dioxo-4-arylbutanoate derivatives were prepared and evaluated for their src kinase inhibitory activity. for this purpose, the appropriate substituted acetophenone derivatives reacted with diethyl oxalate in the presence of sodium ethoxide in dried ethanol to give the corresponding products. all compounds showed moderate activities comparing with staurosporine a...

INTRODUCTION Enantioselective Catalysis Beginning with the first homogeneous asymmetric metal-catalyzed reaction performed by Noyori—a cyclopropanation—the area of enantioselective catalysis in organic chemistry has become a major topic of discussion and research. Homogeneous, asymmetry-inducing catalysts have been developed for a wide range of reactions, especially notable are those developed ...

A homogeneous mixture of Grubbs' catalyst in paraffin wax was shown to catalyze three important types of metathesis reactions: ring-closing metathesis, alkene dimerization, and alkene cross-metathesis (e.g., 11 --> 13). This catalyst preparation demonstrated no loss in catalytic activity after 22 months of storage open to the air.

Heterogeneous rhodium catalysts supported on SiO2 were modified with PPh3 for the gas-phase hydroformylation of propene to produce nand isobutanal. High selectivity to aldehydes was achieved, with no propane or alcohols formed. Investigation of the effects of reaction temperature, reactant partial pressures, total pressure, and PPh3/Rh ratio suggested that the supported catalyst behaved similar...

We found that chemoselectivity of the crossed acyloin product is controlled by the adjustment of the aromatic aldehyde/aliphatic aldehyde ratio. Moreover, we observed the persistent catalytic activity of the homogeneous NHC catalyst in a solution due to NHC catalyst robustness.

An indolinooxazolidine tagged N-heterocyclic carbene Ru olefin metathesis catalyst was synthesized and the molecular structure of this new Ru complex was determined by single crystal X-ray diffraction. This complex is a homogeneous catalyst and can be recovered by controlling the polarity of the indolinooxazolidine tag. Under acidic conditions the indolinooxazolidine tag exists as an open proto...

Herein, we demonstrate that a homogeneous catalyst can be prepared continuously via reaction with a packed-bed of a catalyst precursor. Specifically, we perform continuous proline catalyzed α-aminoxylations using a packed-bed of L-proline. The system relies on a multistep sequence in which an aldehyde and thiourea additive are passed through a column of solid proline, presumably forming a solub...