Mario Pagliaro
Istituto per lo Studio dei Materiali Nanostrutturati, CNR, Palermo, Italy

Due to low turnover numbers, leaching of the metal and quick catalyst deactivation, industry -- eminent colleagues wrote in a presigious journal in early 2016 -- would not use immobilized transition metal complexes as catalysts (1). Joint progress in flow chemistry and in the application of nanochemistry to catalyst making, however, is actually reshaping the way the fine and the pharmaceutical industries produce the active substances for which they exist. 

Writing in a recent issue of OPRD, a team of academic and industrial chemists based in Germany and in the UK, lately provided a nice example (2).

(Rh/(S,S)-EthylDuphos) immobilized on composite support enabling the scale-up of asymmetric hydrogenation of an enamide under flow

The team used an heterogenized Rh chiral metal complex (Rh/(S,S)-EthylDuphos) to mediate the asymmetric hydrogenation of an enamide under flow on kilogram scale with constant high single-pass conversion (>95.0%) and enantioselectivity (>98.6% ee). 

They identified and optimized the (nanochemistry) factors affecting the long-term catalyst stability and enantioselecti ...