Gold‐Catalyzed Oxidation of Alkynes by N ‐Oxides or Sulfoxides

α-Oxo gold carbenes and related carbenoid intermediates are reactive and versatile intermediates in organic synthesis. They can be generated upon the gold-promoted reaction between alkynes and nucleophilic oxidants such as N -oxides and sulfoxides. The overall process is a gold-catalyzed oxidation of alkynes. This approach offers substantially safer access to gold carbenes than those based on the use of hazardous α-diazo carbonyl substrates. This chapter covers the reactions of these catalytically generated reactive intermediates with various heteroatom-based nucleophiles, arenes, alkenes, alkynes and their insertion reactions.