Tandem Synthesis of α-Diazoketones from 1,3-Diketones

A highly efficient synthesis of α-diazoketone was achieved by simply stirring the mixture of 1,3-diketone, TsN 3, and MeNH 2 in EtOH. It was a tandem reaction including a novel primary amine-catalyzed Regitz diazo transfer of 1,3-diketone and a novel primary amine-mediated C–C bond cleavage of 2-diazo-1,3-diketone.