Carbon diselenide
Carbon diselenide is an inorganic compound with the chemical formula . It is a yellow-orange oily liquid with pungent odor. It is the selenium analogue of carbon disulfide () and carbon dioxide (). This light-sensitive compound is insoluble in water and soluble in organic solvents. Synthesis, structure and reactions Carbon diselenide is a linear molecule with D∞h symmetry. It is produced by reacting selenium powder with dichloromethane vapor near 550 °C. It was first reported by Grimm and Metzger, who prepared it by treating hydrogen selenide with carbon tetrachloride in a hot tube. Like carbon disulfide, carbon diselenide polymerizes under high pressure. The structure of the polymer is thought to be a head-to-head structure with a backbone in the form of . The polymer is a semiconductor with a room-temperature conductivity of 50 S/cm. In addition, carbon diselenide is a precursor to tetraselenafulvalenes, the selenium analogue of tetrathiafulvalene, which can be further used to synthesize organic conductors and organic superconductors. Carbon diselenide reacts with secondary amines to give dialkydiselenocarbamates: Safety Carbon diselenide has high vapor pressure. It has a moderate toxicity and presents an inhalation hazard. It may be dangerous due to its easy membrane transport. It decomposes slowly in