Synthesis of Novel Indeno[1,2-c]isoquinoline Derivatives

Abstract

Indeno[1,2-c]isochromene was prepared using the readily obtainable starting materials via the condensation of dimethyl homophthalate with 3,4-dimethoxybenzaldehyde in the presence of sodium methoxide in absolute methanol followed by saponification and cyclization with concentrated sulfuric acid at 0°C. The proclivity of cyclized product for undergoing nucleophilic addition has been tested by reaction with nitrogen nucleophiles. Structural assignments are based on spectroscopic data (infrared, ¹H NMR, ¹³C NMR, and mass spectra) and confirmed by the single-crystal x-ray molecular structure (2 and 3).

Keywords:

• Indeno[1,2-c]isochromene
• isoquinoline derivatives
• nitrogen nucleophiles