Date of Award
Union College Only
Bachelor of Science
The ozonolysis of acetylenes is thought to proceed through the formation of ∝-carbonyl carbonyl oxide intermediates. This reaction has been shown to parallel the effect of molecular oxygen on ketocarbenes. Azibenzil, a diazo-ketone, will decompose to a ketocarbene by the action of heat, light or catalyst. The ketocarbene may decompose by two pathways: Wolff rearrangement and non-rearrangement. The Wolff rearrangement route will produce methyldiphenylacetate (upon addition of methanol), benzophenone, tetraphenylglycolide and possibly other high molecular weight polymeric species. The non-rearrangement pathway will presumably produce ∝-carbonyl carbonyl oxides which will decompose under varying circumstances to produce benzyl, benzoic anhydride, benzophenone, tetraphenylglycolide and other similar polymers. Evidence suggests that the thermal oxygenation of azibenzil proceeds principally via the rearrangement pathway; however, the production of triplet state ∝-carbonyl carbonyl oxides is indicated. The catalyzed reaction also undergoes rearrangement; however, due to the ability of the catalyst to promote intersystem crossing, singlet and triplet state acyl carbonyl oxides are formed. The singlet configuration of this species appears to be responsible for the formation of the benzoic anhydride and of some benzyl. The triplet state can decompose by an alternate method and generate benzophenone, tetraphenylglycolide, polymers and again some benzil.
Westby, Nancy C., "The decomposition of azibenzil in the presence of oxygen" (1978). Honors Theses. 1866.