Synthesis and Use of α‐Diazo Oxime Ethers in the Synthesis of Ethylene Diketone Bis(O‐methyloxime) Derivatives

Reaction of the lithium salts of oxime ethers 4a–c with methanesulfonyl azide gives the α‐diazo oxime ethers 5a–c. These novel compounds are stable up to 90^°C, however, they decompose thermally in refluxing CCl₄ and with PdCl₂ catalysis to yield the ethylene diketone bis(O‐methoxyloxime) derivatives 6a–c in yields of 85–91%. The preparation and characteristic spectral features of 5a–c are described.