An efficient continuous flow approach to furnish furan-based biaryls

Suzuki cross-couplings of 5-formyl-2-furanylboronic acid with activated or neutral aryl bromides were performed under continuous flow conditions in the presence of (Bu)(4)N+F- and the immobilised t-butyl based palladium catalyst CatCart (TM) FC1032 (TM). Deactivated aryl bromides and activated aryl chlorides were cross-coupled with 5-formyl-2-furanylboronic in the presence of (Bu)(4)N+OAc- using the bis-triphenylphosphine CatCart (TM) PdCl2(PPh3)(2)-DVB. Initial evidence indicates the latter method may serve as a universal approach to conduct Suzuki cross-couplings with the protocol successfully employed in the synthesis of the current gold standard Hedgehog pathway inhibitor LDE225.