A QUANTITATIVE INVESTIGATION OF OZONOLYSIS REACTION .7. OZONOLYSES OF PHENYLETHYLENES IN PRESENCE OF OXYGEN-18-LABELED BENZALDEHYDE

The ozonization of cis- and trans-stilbenes, styrene, trans-β-methylstyrene, and triphenylethylene in the presence of18 O-labeled benzaldehyde reveals that the incorporation of the 180 takes place exclusively in the ether oxygen of the ozonides formed. The stilbene ozonide cist trans distributions obtained from these olefins depend on the geometry of the olefin used. The presence of excess benzaldehyde does not affect the cisltrans distributions, and it is therefore unlikely that an initial ozonide-aldehyde reaction is involved. A refined Criegee mechanism is consistent with the observations of the labeling experiments and the stereospecificity of the cis- and trans-ozonides formation. © 1969, American Chemical Society. All rights reserved.