In binary compounds containing halogens, compounds with negative valence of halogens are called halides. It includes fluoride, chloride, bromide, iodide and some halogen interchangeable compounds. According to the properties of halide elements, it can be divided into metal halide and non-metal halide. According to the bond type of halide, it can be divided into ionic halide and covalent halide. Boron, carbon, silicon, nitrogen, hydrogen, sulfur, phosphorus and other non-metallic halides are covalent, and most of them are volatile. All these halides are colourless, high melting crystalline solids having high negative enthalpies of formation.
The Structure of Aryl Halide
The introduction of halogen into drug molecules can improve its pharmacological activity. Halide is an important intermediate in drug synthesis, which can transform a variety of functional groups from halogen. In addition, halogen can be used as the protective group of olefins and other functional groups, which can improve the selectivity of synthesis. Some biological mutants producing strong biological halogenated natural products or their derivatives can be constructed by means of combinatorial biosynthesis, which is of great significance for the production of antibiotics with medical significance.
Metal halides are used in high-intensity discharge lamps called metal halide lamps, such as those used in modern street lamps. Explosion-proof halide lamp is a kind of integrated high light efficiency explosion-proof spotlight, which is suitable for construction lighting in explosion-proof area. In addition, the rich structure and stable skeleton of metal halides will provide more feasible ideas for the design of new solid-state electrolytes and the construction of high-performance lithium-metal batteries.