Synthesis of Unsymmetrical Pyrazines Based on α-Diazo Oxime Ethers

Synthesis of unsymmetrically substituted pyrazines has been a challenge. The reactivity of a-imino carbenoids derived from alpha-diazo oxime ethers has been exploited for pyrazine synthesis, in which the reaction of alpha-diazo oxime ethers with 2H-azirines provides highly substituted pyrazines in good to excellent yields.