Access to Cyclohexadiene and Benzofuran Derivatives via Catalytic Arene Cyclopropanation of α-Cyanodiazocarbonyl Compounds

Catalytic arene cyclopropanation of α-cyanodiazoacetates or α-diazo-β-ketonitriles gave norcaradienes or dihydrobenzofurans, which were converted to cyclohexadienes or benzofurans via cyclopropanation/reductive double ring-opening or DDQ oxidation.