Facile synthesis, sensor activity and logic behaviour of 4-aryloxy substituted 1,8-naphthalimide

A series of 4-phenoxy- and 4-alkoxy-1,8-naphthalimide fluorophores have been synthesized in high yields at room temperature applying novel facile synthesis. One of the compounds was designed as a fluorescent PET sensor according to the “fluorophore-spacer-receptor” model. The ability of this molecule to detect protons and transition metal cations with pronounced selectivity towards Fe3+ was demonstrated. Moreover the 4-phenoxy substituted 1,8-naphthalimides were highly solvent sensitive and able to detect small quantities of water. The potential of the 1,8-naphthalimide sensor to execute INHIBIT logic function at molecular level was also demonstrated.

► Novel blue emitting 4-phenoxy or 4-alkoxy 1,8-naphthalimides are synthesized employing novel facile synthesis.
► 4-Phenoxy-N-(2-dimethylaminoethyl)-1,8-naphthalimide is designed as a PET based sensor for protons and transition metal ions.
► The naphthalimide sensor selectively detects Fe3+ ions.
► 4-Phenoxy substituted 1,8-naphthalimides are highly solvent sensitive and are able to detect small portions of water.
► Novel sensor executes an INHIBIT logic function at molecular level and is applicable for quick identification of concentrated acids.