Triethylamine and TBD supported on silica: Useful heterogeneous catalysts for the reaction of β-dicarbonyl derivatives with α,β-unsaturated compounds under batch and continuous flow conditions

The synthesis of either mono- or bis-adducts via Michael reaction between active methylene compounds and α,β-unsaturated reagents is reported. These processes are catalyzed by two heterogeneous basic catalysts, namely KG-NEt2 and KG-TBD. Both catalysts show good catalytic efficiency and can be reused several times fully preserving their efficiency. The process could be efficiently performed under continuous flow conditions obtaining promising results in term of yield and selectivity