Acid-catalyzed conversion of 1,2-diols to ketones along with the elimination of water as a by-product are collectively called as pinacol rearrangements.

One of such organic reaction is the formation of pinacolone (methyl tert-butyl ketone) from pinacol (2,3-dimethyl-2,3-butanediol) and is famously known as Pinacol-pinacolone rearrangement.

This reaction used only occasionally to synthesize ketones which are very difficult to be synthesized.

General mechanism of these rearrangements is as follows,