Facile synthesis of naphthalene-based porous organic salts for photocatalytic oxidative coupling of amines in air

Abstract

In this report, a new naphthalene-based porous organic salt (NA-POS-1) was synthesized by a facile self-assembly of two sulfonic acid and amine functionalized naphthalene-based building blocks by strong ionic and hydrogen bonding interactions. The obtained NA-POS-1 possesses a crystalline structure, nano-/microrod morphology, considerable porosity and extended naphthalene-based π-conjugated system. Very interestingly, the clever combination of these two naphthalene-based building blocks (NDA and NDSA) endows NA-POS-1 with strong visible-light-harvesting ability and excellent photo-induced charge transfer capability. Therefore, such a π-conjugated organic salt, NA-POS-1, was first regarded as an efficient heterogeneous photocatalyst for visible-light-driven photocatalytic oxidative coupling of amines with O₂ from atmospheric air by virtue of the generated reactive oxygen species, superoxide radical anions, which provides a promising photocatalyst for photocatalytic oxidation reactions. This work provides a new direction for the facile synthesis of more photoactive porous organic salts by combining various π-conjugated organic building blocks for diverse photocatalytic reactions.