PtO 2 /PTSA system catalyzed regioselective hydration of internal arylalkynes bearing electron withdrawing groups.

A highly efficient PtO 2 /PTSA catalyst system for the hydration of a wide array of alkynes was developed. This method proved to be compatible with a large range of functional groups and the ketone products were obtained in high yields. The scope of this methodology was also extended to the synthesis of 3-aryl-isochromenones, -indoles and -benzofurans.