Browse Questions

# Which of the following is used for the conversion of 2-hexyne into trans-2-hexene?

$\begin{array}{1 1}(a)\;H_2/Pd/BaSO_4\\(b)\; H_2,PtO_2\\(c)\;NaBH_4\\(d)\;Li-NH_3/C_2H_5OH\end{array}$

When an alkyne is reduced with $H_2$ in presence of $Pd/BaSO_4$, a cis-alkene is obtained . $H_2/Pt$ will reduce it (alkyne) is an alkane. An alkyne will not be reduced by $NaBH_4$.
A trans-alkene will be formed by reduction of an alkyne by active metal in liquid $NH_3$.
Hence (d) is the correct answer.
edited Mar 25, 2014