Like alkynes (Sections7.4and7.5 ),alkynes can be hydrated by either of two methods. Direct addition of water catalyzed by mercury ion yields the Markovnikov product and indirect addition of water by a hydroboration/oxidation sequence yields the non-Markovnikov product.
Mercury-Catalyzed Hydration of Alkynes
Alkynes don't react directly with aqueous acid but will undergo hydration readily in the presence of mercury sulfate as a Lewis acid catalyst. The reaction occurs with Markovnikov regiochemistry:the-OH group adds to the more highly substituted carbon and the -H attaches to the less highly substituted one