Reaction of one molecule of HBr with one mole | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The reaction of $1,3-$butadiene with $HBr$ produces two isomers: $3-$bromobutene ($1,2-$addition product) and $1-$bromo$-2-$butene ($1,4-$addition

Vedclass · Accepted Answer

$1-$bromo$-2-$butene under thermodynamically controlled conditions

Vedclass · Answer

(B) The reaction of $1,3-$butadiene with $HBr$ produces two isomers: $3-$bromobutene ($1,2-$addition product) and $1-$bromo$-2-$butene ($1,4-$addition product).At low temperatures (e.g.,$-80\,^{\circ}C$),the reaction is kinetically controlled,favoring the $1,2-$addition product ($3-$bromobutene) due to the proximity of the intermediate carbocation.At higher temperatures (e.g.,$40\,^{\circ}C$),the reaction is thermodynamically controlled,favoring the more stable $1,4-$addition product ($1-$bromo$-2-$butene) because the double bond in the $1,4-$product is more substituted and thus more stable.Therefore,at $40\,^{\circ}C$,$1-$bromo$-2-$butene is the major product.

Reaction of one molecule of $HBr$ with one molecule of $1,3-$butadiene at $40\,^{\circ}C$ gives predominantly

Similar Questions

The reaction of $1-$ethylcyclopentene with $BH_3 / THF$ followed by treatment with $H_2O_2 / NaOH$ produces:

What is the major product formed when propene reacts with $ICl$?

Which $\pi$-bond will be reduced first when the compound shown below undergoes catalytic hydrogenation?

$2-$chlorobutane is heated with alcoholic $NaOH$. The product formed in larger amount is:

Vedclass Test Series

Exam Paper Generator

Online Exam Module