Use of Mesoporous Molecular Sieves in the Production of Fine Chemicals: Preparation of Dihydroquinolinones of Pharmaceutical Interest From 2′‐Aminochalcones

Solid catalysts can be an alternative to homogeneous mineral Brønsted and Lewis acids for the synthesis of pharmaceuticals provided that the diffusional and adsorption properties of the reactants and products can be controlled. Structured micro and especially monolayered zeolites and mesoporous materials can be active and selective for intramolecular cyclization reactions and, more specifically, for intramolecular aza‐Michael cyclizations of 2′‐aminochalcones to yield aryl‐2,3‐dihydro‐4(1 H )‐quinolinones of pharmaceutical interest. However, the catalyst deactivates by strong adsorption of the basic quinolinone product. Product desorption has been controlled by optimizing catalyst pore structure and surface composition, together with a proper selection of solvent and reaction temperature. Process intensification for the synthesis of aryl‐2,3‐4(1 H )‐quinolinones of pharmaceutical interest has been achieved by preparing catalysts that allow the one‐pot synthesis of the dihydroquinolinones starting from 2′‐nitrochalcones with excellent yields.