What ketones would be formed from the acid-catalyzed

Solution:

Here we have to find the ketones formed from the acid-catalyzed addition of water to 3-heptyne.

The acid-catalyzed addition of water: - Acid-catalyzed addition of water is also called as acid catalyzed hydration. In this reaction water added with an unsaturated substrate in presence of an acid. Here the acid acts as the catalyst. The common acid catalysts are sulfuric acid and phosphoric acid.

Step 1

The acid-catalyzed hydration can be carried out for the both symmetrical and unsymmetrical alkyne.

The symmetrical alkyne on addition with water in presence of an acid gives ketone whereas unsymmetrical alkyne gives a mixture of two ketones because the Oxygen atom can add to either of the alkyne C-atoms.  

R-C≡C-R + H₂O →    R-CH₂-CO-R

               (symmetrical alkyne)              (Ketone)

R-C≡C-R' + H₂O → R-CH₂-CO-R' + R-CO-CH₂-R'

              (unsymmetrical alkyne)         (Mixture of Ketones)