Question

Draw the structure of the starting material needed to make 2‑methylhept‑3‑yne (or 2‑methyl‑3‑heptyne) using sodium amide in liquid ammonia, followed by 1‑bromopropane.

Answer 1

Answer:

See explanation and image attached

Explanation:

2‑methylhept‑3‑yne can be made by the reaction of the compound shown in the image attached with soidamide in liquid ammonia and 1‑bromopropane.

The first step in the reaction is the deprotonation of the alkyne starting material by the amide ion.

This step is followed a nucleophilic substitution reaction of the alkyne with 1‑bromopropane to yield the 2‑methylhept‑3‑yne product.