Selection of the most appropriate catalyst for Pd-catalyzed Sonogashira coupling often requires time and resources. We applied a continuous flow device for rapid catalyst screening of 4 heterogeneous catalysts over 6 Sonogashira coupling reactions together with longevity estimation. The screening procedure requires only 8 hours. For coupling the alkynes with 4-iodo-anisole Fibrecat types of catalysts showed the highest performance, while when 4-bromoanisole was applied as an aromatic halide PdCl 2 (PPh 3 ) 2 DVB gave superior results. For phenylacetylene and ethynyl-cyclohexene the coupling of the bromo derivative resulted in relatively low conversion as well as selectivity for most of the polymer-bound catalysts. Applying the cheap catalyst 10 % Pd/C the coupling reaction could only be achieved with the rather reactive 4-iodo-anisole although with moderate conversion.
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