(a) Wurtz reaction
Alkyl halides react with sodium in presence of dry ether to form higher alkanes. For example, methyl bromide reacts with sodium in presence of dry ether to form ethane.
CH3−Br+2Na+Br−CH3dry ether−−−−−→CH3−CH3+2NaBr
(b) Wurtz-Fittig reaction
Aryl halides react with alkyl halides in presence of sodium to form substituted aromatic compounds. For example, bromobenzene reacts with methyl iodide in presence of sodium to form toluene.
C6H5−Br+2Na+I−CH3→C6H5−CH3+NaBr+NaI