On the regioselective molecular sieves-promoted oxidative three-component synthesis of fused-benzimidazoles from β-ketoesters

The regioselectivity of molecular sieves-promoted oxidative three-component reaction between beta-ketoesters, aromatic o-diamines and acrolein, leading to pyrido[1,2-a]benzimidazoles, has been investigated by a combination of experimental and theoretical studies. Molecular sieves act both as heterogeneous catalyst and dehydrating agent and their role has been modeled in the theoretical approach. The modulation of the reactivity of the aromatic diamine partner as a function of the nature of the substituents of the aromatic ring and its influence on the regioselectivity of the reaction could be rationalized.

Automated summary

The regioselectivity of the oxidative three-component reaction between beta-ketoesters, aromatic o-diamines and acrolein, promoted by molecular sieves, has been investigated. The role of molecular sieves as a heterogeneous catalyst and dehydrating agent has been modeled in the theoretical approach. The influence of the nature of the substituents of the aromatic ring on the reactivity of the aromatic diamine partner and its impact on the regioselectivity of the reaction could be rationalized.