Continuous tubular flow reactor for XAFS studies of organometallic reactions: Possibilities and limitations for studies of the Soai reaction

Recent XAS studies into Homogeneous metal catalyst in fine chemical and pharmaceutical syntheses

“…A number of technological solutions for these problems have been developed. These include stopped-flow freeze-quenching to prolong the life-time of intermediates [ 30 ], and multiple-windows flow-reactors which enable steady-state observation of a reaction at different reaction time by controlling the flow-rate [ 8 ]. Many XAS studies on more challenging homogeneous catalytic reactions can therefore be expected in the near future.…”

“…In addition, time resolved in situ studies sometimes suffer from sample decomposition by radiation, which necessitates spectroscopic flow-cells through which reaction mixtures can be pumped continuously. These flow-cells also enable steady state measurements and time resolution through changes to residence time and flow-rate [ 8 , 9 ]. When such problems are overcome, XAS has been demonstrated to be a highly effective method, and in some cases the only appropriate method, to answer many mechanistic questions in homogeneous catalysis.…”

A versatile liquid-jet/sessile droplet system for operando studies of reactions in liquid dispersions and solutions by X-ray absorption spectroscopy

“…When a process involves nucleation, adsorption or precipitation of solid particles, deposition on the window materials can occur, resulting in XAS analysis of an unrepresentative aliquot of the reaction mixture. 7 For tender X-ray experiments, fluorescence-yield (FY) detection is particularly affected compared with transmission as it is surface rather than bulk sensitive. Windowless probing of multiphase samples avoids these problems and has been explored for a variety of X-ray sample environments, including supported and hanging droplets, 8,9 levitated droplets, 10 static solutions 11,12 and liquid-jets.…”