Halogenated hydrocarbons vinyl bromide

Although most of the halogenated hydrocarbons that are commonly used are liquids at ambient temperature and pressure, the low-molecular-weight compounds such as 1,2-difluoroethane, methyl bromide, or vinyl chloride are gases, whereas those of higher molecular weight, such as iodoform or hexachloronaphthalene, are solids. Halogenated hydrocarbons are used as solvents. 

NH, NH-, -CN), silicon and olefinic double bonds are more polymerizable while those containing oxygen (e.g. -C=0,-0-,-0H), chlorine, aliphatic hydrocarbon and cyclic hydrocarbons tend to decompose. Brown (13) reported in his studies of a series of vinyl halides that the dihaloethylenes polymerize more rapidly than the corresponding monohalides and that chlorides and bromides polymerize more rapidly than the fluorides. Kobayashi, et. al. (IJ) found that the additons of certain halo-genated compounds to hydrocarbon monomer streams often dramatically increases the polymerization rate. Thus, these halogenated compounds may be considered to act as gas phase catalysts for the plasma polymerization of hydrocarbons. 

LAH in THF reduces chlorides, bromides, and iodides to hydrocarbons, whatever their degree of substitution (primary, secondary, tertiary, aromatic, vinyl, and cyclopropyl). The order of reactivity for a given hydrocarbon residue is iodide > bromide > chloride. For a given halogen, the order of reactivity is ArCH2X = allylX > RCHjX > RjCHX > R3CX. 

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