ZnCl2-Promoted Three-Component Reaction of 2-Aminochromenones, Aromatic Aldehydes, and Quinone Monoketals: Access to 5,6-Dihydro-12H-chromeno[2,3-c]isoquinolin-12-one Derivatives

A three-component reaction of 2-amino-4H-chromen-4-ones, aromatic aldehydes, and 4,4-dialkoxycyclohexa-2,5-dien-1-ones for the concise synthesis of chromeno-[2,3-c]-dihydro-isoquinoline derivatives has been investigated. This reaction involved consecutive ZnCl2-promoted Micheal addition and intramolecular Friedel-Crafts alkylation. This synthetic protocol offered several advantages, including the readily accessible starting materials, good functional group tolerance, and simplicity of operation. Additionally, the structures of products obtained were determined based on X-ray diffraction studies.

Automated summary

A three-component reaction was investigated for the concise synthesis of chromeno-[2,3-c]-dihydro-isoquinoline derivatives, involving consecutive ZnCl2-promoted Micheal addition and intramolecular Friedel-Crafts alkylation. This synthetic protocol offered advantages of readily accessible starting materials, good functional group tolerance, and simplicity of operation.