Ein Kartuschen-System für die metallorganische Katalyse: sequenzielle Katalyse und Stofftrennung mit überkritischem CO2zur Kontrolle der Löslichkeit

Batchwise and continuous organophilic nanofiltration of Grubbs-type olefin metathesis catalysts

A mass-tagged N-mesityl imidazolinium salt with four additional -CH(2)NCy(2) substituents was synthesized, leading to a molecular mass of nearly 1100 g mol(-1) in the corresponding carbene ligand. This mass-tagged ligand was used to generate the respective Grubbs II and Grubbs-Hoveyda type complexes. The catalytic activity of the latter complex was tested in several olefin metathesis reactions and found to be slightly superior to that of the related N-mesityl based complex. In batchwise solvent resistant nanofiltration experiments the ruthenium complex dissolved in toluene and following a metathesis reactions was efficiently retained (>99.8 %) by a single nanofiltration; the permeate contained less than 4 ppm of Ru. Equally efficient catalyst retention was observed in a membrane reactor utilized for the continuous synthesis of a RCM product.

Poly(ethylene glycol) stabilized Co nanoparticles as highly active and selective catalysts for the Pauson–Khand reaction

PEG-stabilized cobalt nanoparticles were prepared by thermal decomoposition of [Co2(CO)8] in PEG and were shown to be highly active and selective catalysts, for intra- and intermolecular Pauson-Khand reactions (PKR), in organic solvents or aqueous media.