Naphthalene is a hydrocarbon produced by the distillation of coal tar and is an aromatic white crystalline substance. Naphthalene is the most abundant component in coal tar. It is used as an insect repellant and insect fumigant. The compound is used in the manufacture of celluloid, dyes, hydrogenated naphthalenes, oil fumes, smokeless powders and synthetic resins.
The two N atoms in Benzothiadiazole could possibly form intermolecular hydrogen bonding, leading to a more planar backbone. Benzothiadiazole is a strong electron-accepting molecular fragment. By fusing it with thiazole donor-acceptor dyes, near-infrared fluorescence was created. The benzothiadiazole ring is a useful n-type building block for designing electron-transport materials for organic and polymer light-emitting diodes (LEDs). Arene- and heteroarene-fused thiadiazoles have also found use in the design of low-band-gap materials for the construction of organic field-effect transmitters (OFETs), as stable organic radicals, and as one or two photon-absorbing materials for the design of nonlinear near-infrared (NIR) dyes. Benzothiadiazoles acting as the electron-accepting cores have been incorporated into dendrimer-type light-harvesting materials.