Question

2-Bromobutane to but-2-ene

Hint:

An E2 elimination mechanism involves the simultaneous removal of a proton and a leaving group, resulting in the formation of an alkene.

Answer 1

Conversion of 2-Bromobutane to But-2-ene 

To convert 2-bromobutane into but-2-ene, an elimination reaction (E2 mechanism) is used. This reaction requires a strong base like potassium hydroxide (KOH).

In the E2 reaction, the base abstracts a proton from the β-carbon (the carbon adjacent to the one bonded to the bromine), and the bromine atom leaves simultaneously, resulting in the formation of a double bond (alkene).

Reaction Equation:

\( \text{CH}_3\text{-CHBr-CH}_2\text{-CH}_3 \xrightarrow{\text{alc. KOH, heat}} \text{CH}_3\text{-CH=CH-CH}_3 \)

Product: But-2-ene (major product due to Zaitsev’s rule, which favors the more substituted alkene).