Methodological Optimization of Catalytic Hydration of Alkynes with Mercury( II) p-Toluensulfonamidate Under Neutral Conditions

A systematic optimization study of reaction conditions of alkyne hydration, catalyzed by mercury(II) ptoluensulfonamidate is described. Hydration takes place under catalytic conditions by using from 0.01 to 0.2 equivalents of the easily available and inexpensive mercury(II) p-toluensulfonamidate in a hydroalcoholic solution, under mild and neutral conditions. Different reaction parameters like temperature, concentration of substrates, equivalents of water and catalyst, portionwise addition of the catalyst, thermal, microwave and ultrasound activation conditions and solvent type have been studied and optimized.