OXIDATION OF ORGANIC COMPOUNDS WITH CERIUM(4) .8. OXIDATION OF BICYCLO[2.2.1]-2-HEPTANOLS AND BICYCLO[2.2.2]-2-OCTANOL

It is reported that oxidation of either exo- or-endo-2-norbornanol with 2 equiv of ceric ammonium nitrate in 50% aqueous acetonitrile at 50° gave three major products, 3- and 4-cyclopenteneacetaldehydes and 3-ni-tratocyclopentaneacetaldehyde. Oxidation of bicyclo[2.2.2]-2-octanol under these conditions was found to give 4-cyclohexeneacetaldehyde, and cis- and trans-4-nitratocyclohexaneacetaldehydes. Structure proofs for these products are described. The major product from the oxidation of either borneol or isoborneol under these conditions was found to be α-campholenic aldehyde. These results clearly indicate that oxidative cleavage is the preferred mode of oxidation of bicyclo[2.2.1]-2-heptanols and bicyclo[2.2.2]-2-octanols by ceric ammonium nitrate. From these and other experimental results a mechanism is proposed which involves complex formation between the cerium(IV) and alcohol followed by decomposition of this complex with cleavage of the C1¯C2 bond to ive a radical which is then oxidized by another ceric species. © 1969, American Chemical Society. All rights reserved.