\(X\) is the product obtained by hydrolysis of prop-1-yne in the presence of mercuric sulphate under dilute acidic medium. \(Y\) is obtained by the reaction of ethanenitrile with methyl magnesium bromide in dry ether followed by hydrolysis. IUPAC name of product obtained from \(X\) and \(Y\) in presence of barium hydroxide followed by heating is :