Wurtz fittig reaction is used for alkylation of aryl halides.While in Wurtz reaction,two moles of alkyl halides reacts with two moles of sodium molecule to produce symmetrical alkane.
CH3Br +2Na + CH3Br ? CH3 CH3 + 2NaBr
In case, two different alkyl halides are taken in order to prepare alkane with odd number of carbon atoms, a mixture of three alkanes will be produced as follows:
Therefore, this method is not suited to prepare alkanes containing odd number of carbon atoms. Methane, however, cannot be prepared by this method.