THE 13C CIDNP STUDIES ON THE PHOTOLYSIS OF METHYL DIAZOACETATE IN CHLORO-SUBSTITUTED METHANES

The photolysis of methyl diazoacetate in CCl4, CHCl3, CH2Cl2, and CFCl3 has been examined by the 13C CIDNP methods. The insertion products Cl2XCCHClCO2CH3 (X=Cl and H) show emission for the carbonyl and C-3 carbons and enhanced absorption for C-2. The cage recombination of geminate pairs ‾Cl2XC· ·CHClCO2CH3 formed by the cleavage of the corresponding chloronium ylides is responsible for the polarization.