Question

$3,3$-Dimethylbutan- $2$- ol loses a molecule of water in the presence of a concentrated sulphuric acid to give tetramethylethylene as a major product. Suggest a suitable mechanism.

Answer 1

This is done in 4 steps:

1. Protonation of hydroxyl group.

2. The removal of water to form a secondary carbonium ion.

3. The conversion of secondary carbonium to the more stable tertiary carbonium ion by the shift of methyl group.

4. The removal of $H^{+}$ to form a double bond.