Hydrocarbons Ques 22
22. Which one of the following alkenes will react faster with $H_2$ under catalytic hydrogenation conditions?
[2005] (a)
(b)
Show Answer
Solution:
Option (a) and (b) are more stable due to more hyperconjugated $(6 \alpha-H)$ hydrogen atoms. cis-2-butene (option a) is less hindered than 2-methyl propene (option b).
Thus, hydrogenation will be fastest for trans-2-butene.
As catalytic hydrogenation occurs on the surface of the catalyst, the rate of catalytic hydrogenation depends on the stability of the alkene and steric hindrance on the molecule.
BETA
