The IUPAC name of the compound having the formula $\mathrm{CH} \equiv \mathrm{C}-\mathrm{CH}=\mathrm{CH}_2$ is
The IUPAC name of the compound having the formula $\mathrm{CH} \equiv \mathrm{C}-\mathrm{CH}=\mathrm{CH}_2$ is
3-butene-1-yne
1-butyn-3-ene
but-1-yne-3-ene
1-butene-3-yne
Solution
\(\begin{array}{c}
&\stackrel{4}{\mathrm{C}} \mathrm{H} \equiv \stackrel{3}{\mathrm{C}}-\stackrel{2}{\mathrm{C}} \mathrm{H}=\stackrel{1}{\mathrm{C}} \mathrm{H}_2\\
&\text { 1-Butene-3-yne }
\end{array}\)
Since the sum of numbers starting from either side of the carbon chain turns out to be the same, so lowest number is given to the C = C end.