Metal salt catalyzed carbenoids. XVIII. The electron impact mass spectral behavior of diazocarbonyl compounds. I.

Electron impact (EI) mass spectral studies of methyl diazoacetate, ethyl diazoacetate (1), methyl diazoacetoacetate (2), and dimethyl diazomalonate (3) indicate that loss of N2 is exceedingly difficult from the parent ion and was observed only with 3. Diazoacetylacetone exhibits an appreciable (M − 28)+. ExactMass and metastable transitions indicate fragmentation occurs in part via 1,2,3-oxadiazolium ion-radicals (6) or α-lactones (7) to furnish N2O and hyponitrite esters. (M − 28)+ from 1 results from loss of ethylene.