Naphthyridine Derivatives as a Model System for Potential Lithium-Sulfur Energy-Storage Applications

Naphthyridines have been identified as structural elements in sulfurized polyacrylonitrile, which is a common electrode material in lithium-sulfur batteries. Some dibenzonaphthyridine derivatives with a fused dithiolo moiety were prepared as model compounds for battery studies. These heterocyclic systems were prepared via the corresponding diphenyldicarbamide intermediate. Followed by naphthyridione formation, stepwise installation of the dithiolane subunit occurred in a straightforward manner. In the solid state, the heteroaromatic system is completely planar and was thoroughly characterized. Initial battery cycling tests indicated a potential use of such structural motifs in sulfur-lithium systems.