Reaction of one molecule of HBr with one molecule of 1,3-butadiene at `40^(@)`C gives predominantly.

Options

A. 3-bromobutene under kinetically controlled conditions
B. 1-bromo-2-butene under thermodynamically controlled conditions
C. 3-bromobutene under thermodynamically controlled conditions
D. 1-bromo-2-butene under kinetically controlled conditions

Answer

B

Explanation

The electrophilic addition reaction of hydrogen bromide to 1, 3 – butadiene at `40^@C` gives predominantly thermodynamically more stable 1, 4 adduct, 1– bromo but – 2 – ene.