Structure Organic halogen compounds are very common and important classes of organic molecules.
Many organic halides occur in nature and others are produced in the laboratory.
Thyroxine, a thyroid hormone, is an aryl iodide. Alkyl halides are nonflammable and nonpolar. These properties have made them useful as solvents for dry cleaning and degreasing applications. However, the toxicity of these compounds has led to substitutes for most of these applications. Even though chlorofluorocarbons are nonflammable, nontoxic and have mechanical properties that make them good refrigerants in air conditioners and refrigerators, the stability of these compounds in the troposphere and their ability to break down stratospheric ozone have led to a ban on these compounds.