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A new catalytic method for the construction of the quinobenzoxazine core has been developed employing the gold-catalyzed cyclization of o -azidoacetylenic ketones in the presence of anthranils. The overall process comprises of a gold-catalyzed 6- endo-dig cyclisation of o -azidoacetylenic ketone leading to a α-imino gold carbene and subsequent carbene transfer to anthranil leading to the 3-aryl-imino-quinoline-4-one intermediate, which undergoes 6π-electrocyclization and aromatization to form the central quinobenzoxazine core. This transformation provides a new approach to a diverse array of quinobenzoxazine structures, in addition to being scalable and having mild reaction conditions.