Ozonolyse von Enolethern, 8. Mitteilung

Ozonolysis of Enol Ethers. Part 8. Ozonation of (1‐Methoxy‐2‐methylprop‐1‐enyl)‐1,1′‐biphenyl in Comparison with Related Oxygenations The results of conversions of 4‐(1‐methoxy‐2‐methylprop‐1‐enyl)‐1,1′‐biphenyl ( 19 ) with ozone and with dimethyldioxirane ( 6b ) under ‘normal' and ‘inverse' conditions are compared with oxygenations by dioxygen under thermal and sensitized photochemical conditions, as well as with the photooxygenation of epoxide 17 , formally derived from 19 . Ozone consumption varies between 0.7 and 1 mol‐equiv. amounts, peroxidic species are not formed. Except for bicyclus 24 , all conversions lead to mixtures of the same 1,1′‐biphenyl]‐4‐yl compounds which only differ by varying percentages. It is concluded that ozonolysis of CC bonds only represents a special type of electron‐transfer oxygenation.