Organocatalytic Oxidative Functionalizations of Alkynes

The catalytic oxidation of alkynes has traditionally belonged to the domain of transition metal catalysis. Recently, several promising organocatalytic methods have been developed, leading to selective oxidative transformations of alkynes. For example, ynamides, because of their electron-rich alkynes, are ideal candidates for Bronsted acid-catalysis. A closely related keteniminium intermediate could also be accessed via amide activation. A particularly interesting aspect in this regard is a facile access to umpolung enolates, which would enable novel disconnections with complementary selectivity to traditional methods.