α-Iodination of Ketones with MnO₂/I₂ Reagent Combination: A New Environmentally Friendly Procedure

Abstract

In alcoholic media, α-iodination of ketones was accomplished using MnO₂/I₂ reagent combination in a new, environmentally friendly procedure. The reactions carried out under thermal conditions or microwave irradiation afforded α-iodo ketones in reasonable to good yields.

Key words

iodine - manganese oxide - halogenation - ketones

References

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15

We have observed that shorter reaction times (e.g., 1 h 30, 3 h 30 and 12 h) led to partial α-iodination of tetralones and after optimization, refluxing for 18 h led to better yields of iodo compounds.

16

Starting materials (ketones) and α-iodo ketones were easily separated by chromatography on silica gel.