Dynamic methods and new reactors for liquid phase molecular catalysis

Kinetic data acquisition and screening of transition metal complexes for ho mogeneous liquid phase catalysis calls for numerous testing in multiphase G /L, L/L and G/L/L systems. It is shown first, with an example in asymmetric hydrogenation, why detailed kinetics must be performed. Then, new reactors leading to fast experimental techniques are proposed. A liquid-liquid cent rifugal partition chromatography is evaluated for determining rate constant s and partition isotherms by combining frontal analysis and elution chromat ography, the catalyst being maintained in a stationary aqueous phase. Two m icroreactors offering short residence time have also been tested and compar ed with a fast test reaction (t(R) ca. 5-20 s). The combination of reacting pulses, carrier liquids and micromixer is proposed as a general high throu ghput tool for the investigation of G/L, L/L and G/L/L catalytic systems in a fast sequential way. (C) 2001 Elsevier Science B.V. All rights reserved.