Cross-Coupling in a Flow Microreactor

Br-Li exchange of ArBr with BuLi in a microreactor was enabled by the use of palladium catalysts bearing a carbene ligand. 

A cross-coupling of two different aryl bromides occurred within a minute without necessitating low temperatures (—78 °C) needed in a conventional process. 

In the case of heteroaromatic compounds, the use of H-Li exchange enabled cross-coupling of ArH and ArBr. Hence, the method greatly enhances the synthetic utility of organolithium compounds and adds a new dimension to the chemistry of cross-coupling. Wider scope and limitations of this useful transformation are under investigation. 

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Nagaki A, Kemnoku A, Moriwaki Y et al (2010) Cross-coupling in a flow microreactor. Space integration of lithiation and Murahashi coupling. Angew Chem Int Ed 49 7543-7547... 

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