Q. What is the product when 2-butyne is treated with liquid $NH_{3}$ in presence of lithium?
A) $n$-butane
B) $cis$-2-butene
C) $trans$-2-butene
D) 1-butene
Explanation
(c)
$CH_{3} - C \equiv C - CH + 2(H)\underset{liq.NH_{3}}{\overset{\ \ \ \ \ \ \ \ \ \ Li\ \ \ \ \ \ \ }{\rightarrow}}$
[image:13_image315.emf]
2-butyne
But in presence of Lindlar’s catalyst $(Pd - CaCO_{3})$ 2-butyne reacts with hydrogen giving $cis$-2-butene.
$CH_{3} - C \equiv C - CH + H_{2}\overset{Pd - CaCO_{3}}{\rightarrow}$
(2-butyne)
[image:13_image316.emf]
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.