Ions α-cétocarbenium : Influence de la nature de la fonction carbonyle sur la reactivite des ions α-ceto 4-t.Bu cyclohexylcarbenium

α-keto 4-t.Bu cyclohexylcarbenium ions formed by AgSbF₆-CH₂Cl₂ dehalogenation of α-keto 1-bromo 4-t.Bu cyclohexanes, give the corresponding α-ethylenic carbonyl compounds and bicyclic oxonium salts. The ratio of products does not vary according to the electronic environment of the carbonyl function but depends on the size of the adjacent group, suggesting that the α-ketocarbenium ion conformation determines the product ratio.