Photoreduction of Hexafluorobiacetyl by Hydrocarbons in the Gaseous Phase and in Solution

Mechanisms of photochemical reactions in solution. LVIII. Photoreduction of camphorquinone

“…28 Under our experimental conditions a splitting constant as low as 0.5 G would most likely not have been observed. It should be noted that a symmetrical structure has not been observed for the analogous radical derived from biacetyl (8). In neutral media the two methyl groups show very different Acm values and an additional splitting of 2.07 G, assigned to the hydroxyl hydrogen, is observed.29•30 While it is possible that the splitting constant assigned to H4 in the spectrum of 7 is due to the hydroxyl proton, it is unlikely in view of the similarity of the splitting constants for H5, H6, and that for one of the methyl groups of 6.…”