Question

Draw the alkane formed when 4,5,5‑trimethyl‑1‑hexyne or 4,5,5‑trimethylhex‑1‑yne is treated with two equivalents of hbr.

Answer 1

2,2 - dibromo - 4,5,5 - trimethylhexane

Step-by-step explanation:

When 2 equivalents of HBr are added to 4,5,5‑trimethyl‑1‑hexyne, the alkane (at the top right of the image) is formed. The bromine branches are added to the second carbon because the intermediate carbocations are the most stable on the secondary carbon. Below I have drawn the mechanism.