B 2165 (OTTO) 1-Bromo naphthalene, 98% Cas 90-11-9 - used in organic synthesis and refractometry of fats. B 2165 (OTTO) 1-Bromo naphthalene, 98% Cas 90-11-9 - used in the preparation of N-aryl imidazoles and diaryl ethers. It is used to determine the refractive index of crystals and the water content of alcohols. It is utilized in the preparation of glutathione peroxidase-like antioxidant activity of diaryl diselenides.