\(3C{H_3} - CH = C{H_2} + B{H_3}\,\xrightarrow{{{\text{(Hydroboration)}}}}\) \({(C{H_3}C{H_2}C{H_2})_3}B\) \(\xrightarrow[{{\text{(Oxidation)}}}]{{{H_2}{O_2}/O{H^ - }}}\) \({\text{3 C}}{{\text{H}}_3}{\text{C}}{{\text{H}}_2}{\text{C}}{{\text{H}}_2}{\text{OH}}\)
$C{H_3}C{H_2}OH\xrightarrow{{P + {I_2}}}A\xrightarrow{{Mg}}B\xrightarrow{{HCHO}}C\xrightarrow{{{H_2}O}}D$