c
\(\mathop {\mathop {C{H_3}C{H_2}C{H_2}Br}\limits_{1 - bromopropane} }\limits_{(X)} \) \( + Mg \stackrel{\text { Dry ether }}{\longrightarrow} CH _{3} CH _{2} CH _{2} MgBr\) \(\xrightarrow{{HCHO}}\) \(CH _{3} CH _{2} CH _{2} CH _{2}- O - MgBr\) \(\xrightarrow{{{H_2}O}}\) \(\mathop {C{H_3}C{H_2}C{H_2}C{H_2}OH}\limits_{1 - bu\tan ol} + Mg < _{OH}^{Br}\)