Synthesis and fluorescence properties of N-methyl-1,2-dihyroquinoline-3-carboxylate derivatives: light-emitting compounds in organic solvent, in neat form, and in water

Abstract

The reaction of N-methyl-3-(arylamino)acrylates with in situ generated HI in CH₃CN gave N-methyl-1,2-dihydroquinoline-3-carboxylates, which exhibited fluorescence at 490–560 nm in THF solution with good quantum yields (Φ_F = 0.5–0.9). Electron-withdrawing substituents at the 6-position promoted high quantum yields. N-Methyl-1,2-dihydroquinoline-3-carboxylates were also emitted in neat form. Photoluminescence was observed from the dicarboxylic acid hydrolysis products in water without any organic co-solvent.