Preparation, spectroscopic properties, and ion chemistry of 3-diazo-1,1,1-trifluoro-2-propanone

Article abstract of DOI:10.1139/v96-151

The title compound (1) is prepared in satisfactory yield by reacting CH₂N₂ with trifuoroacetic anhydride in Et₂O; the d-analog was obtained by exchange with D₂O. ¹H, ¹³C, ¹⁵N, ¹⁷O, and ¹⁹F NMR spectra of 1 were studied, as well as its IR spectrum. A single isomer is present corresponding to the more stable Z configuration. The structural assignment was made on the basis of quantum mechanical calculations, which revealed that the Z form is some 13.4 kJ mol^-1 more stable than the E form and the activation energy for the E → Z transition is 64.2 kJ mol^-1. Mass spectra under different experimental conditions were recorded and breakdown pathways of the parent ion of 1 charted.