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The direct α-iodination of various ketones using iodine-ammonium cerium(IV) nitrate in acetic acid or alcohol gave the corresponding α-iodo ketones in high yields. The effect of cerium salt on the iodination of ketones, and the iodination of 5α-cholestan-3-one using several methods are also discussed. In the reaction of 3,3,5-trimethylcyclohexanone and unsymmetrical ketones, such as 2-hexanone and 2-heptanone, using methanol, ethanol, 1-propanol, and 2-propanol, the regioselective iodination product was obtained. In the case of bromination, the reaction of ketones with bromine and ammonium cerium(IV) nitrate also yielded the corresponding α-bromo ketones.

The reaction of cycloalkene with iodine-cerium(IV) ammonium nitrate (CAN) in acetonitrile-water (10 :1-1:1) affords the corresponding trans-iodohydrins and trans-iodonitrates; when iodine-cerium(IV) sulfate (CS) in acetonitrile-water (10 :1) at 50 °C is used, trans-iodohydrins are obtained preferentially.