Like alkynes (Sections 7.4 and 7.5 ),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