Kumada-Corriu Reactions Investigated in Micro Reactors

3 Kumada-Corriu Reactions Investigated in Micro Reactors Organic synthesis 47 [OS 47] Reaction between 4-bromoanisole and phenylmagnesium bromide [2] 

In a Kumada-Corriu reaction, an aryl halide is oxidatively coupled with a homogeneous nickel(ll)-phosphine catalyst [2], This species reacts with a Grignard reagent to give biaryl or alkylaryl compounds. Later, palladium-phosphine complexes were also successfully applied. By this means, stereospecific transformations were achieved. 

The Kumada-Corriu reaction is characterized by mild conditions and clean conversions [2]. A disadvantage of previous Kumada-Corriu reactions was due to the use of homogeneous catalysts, with more difficult product separation. Recently, an unsymmetrical salen-type nickel(II) complex was synthesized with a phenol functionality that allows this compound to be linked to Merrifield resin polymer beads (see original citation in [2]). By this means, heterogeneously catalyzed Kumada-Corriu reactions have become possible. 

Kinetics rate constant/reaction time - benchmarking with batch processing 

R X R Flow rate (pi Rate constant k (Ur s ) Rate constant k (Ur s ) Rate enhancement (-fold) 

---