In the addition of HBr to 1-butyne,the nucleophile in the first step of the mechanism is
A)the Csp-H1s bond of 1-butyne.
B)the C-C triple bond of 1-butyne.
C)the H atom in HBr.
D)the Br ion.

Question

Quizplus · Accepted Answer

The C-C triple bond of 1-butyne acts as the nucleophile in the first step of the mechanism, attacking the proton (H+) from HBr, because it has a high electron density due to the π bonds, making it attractive to electrophiles like H+.

In the Addition of HBr to 1-Butyne,the Nucleophile in the First