Mono halogen methanes

Methyl Halides.— The mono-halogen substitution products of methane, of which we have been speaking, are known by this new system of names as methyl compounds so that we have the two sets of names for the same substances, both of which are correct and either of which expresses the relationship to methane. 

Bowman, R., Stangland, E., Jones, M., etal. (2010). Worldwide Patent 2010062427A2, Oxidative Mono-Halogenation of Methane (Dow Global Technologies Inc., USA.). 

Chlorine or bromine reacts with alkanes in the presence of light (hv) or high temperatures to give alkyl halides. Usually, this method gives mixtures of halogenated compounds containing mono-, di-, tri- and tetra-halides. However, this reaction is an important reaction of alkanes as it is the only way to convert inert alkanes to reactive alkyl halides. The simplest example is the reaction of methane with CI2 to yield a mixture of chlorinated methane derivatives. 

This type of reactions are very common in organic chemistry (substitution reaction). For example the chlorination of methane may give mono, di, tri and/or tetra halogen derivative. 

Isomerism of Di-chlor Ethanes.—When, however, we study the constitution of the poly-halogen ethanes we find that isomerism occurs just as in the case of the propyl iodides and of the hydrocarbons above propane. In the case of ethane it is a fact that only one mono-substitution product of any type is known, thereby proving the symmetry of the ethane molecule and the like character of all six of the hydrogen atoms. When two hydrogen atoms are substituted by two chlorine atoms two dif event compounds are produced both having the composition C2H4CI2. From the constitution of the ethane molecule, that has been established by its synthesis from methane (p. 16), we can readily see how this may be explained as we may have two hydrogen atoms replaced by two chlorine atoms in two different ways, as follows ... 

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