Here an alkyl halide is first converted to lithium dialkyl cuperate, ${\text{R}}_{\text{2}}\text{CuLi}$, which on reaction with alkyl halide gives an alkane. This method is also suitable for the preparation of unsymmetrical alkane of the type $\mathrm{<math>\; <mtext>R</mtext>\; </math>}-{\mathrm{<math>\; <mtext>R</mtext>\; </math>}}^{\prime }$, where $\mathrm{<math>\; <mtext>R</mtext>\; </math>}\ne {\mathrm{<math>\; <mtext>R</mtext></math>}}^{\prime }$.