[2232-12-4]  · C5H6I2N2O2  · 1,3-Diiodo-5,5-dimethylhydantoin  · (MW 379.92)

(electrophilic iodination)

Alternate Name: DIH.

Solubility: sol acetone; slightly sol CH2Cl2.

Preparative Method: by reaction of Iodine Monochloride (0.11 mol) with 5,5-dimethylhydantoin (0.05 mol) and Sodium Hydroxide (0.1 mol) in ice-water at 0 °C;1 the product is used without further purification.

Handling, Storage, and Precautions: store under nitrogen at 0 °C and protect from light and moisture to avoid decomposition; irritating solid; avoid inhalation of the powder.

DIH has been used for the same electrophilic iodination of many organic compounds for which N-Iodosuccinimide is used. The advantages of DIH include its high iodine content, satisfactory stability, and its economical preparation (which does not require expensive silver salts), whereas its disadvantages include its limited solubility. In the few reported examples, DIH has been found to achieve the electrophilic iodination of organic compounds with results comparable to or better than those obtained using N-iodosuccinimide. These applications have included the electrophilic iodination of electron-rich arenes using DIH in acetone and the preparation of a-iodo ketones by reaction of enol acetates with DIH in dioxane at 90 °C.1 In addition, DIH has been used for the preparation of 1,2-dioxetanes by iodohydroperoxylation of alkenes and for the cleavage of dithiane protecting groups.2,3

1. Orazi, O. O.; Corral, R. A.; Bertorello, H. E. JOC 1965, 30, 1101.
2. Kopecky, K. R.; Filby, J. E.; Mumford, C.; Lockwood, P. A.; Ding, J.-Y. CJC 1975, 53, 1103.
3. Corey, E. J.; Tius, M. A.; Das, J. JACS 1980, 102, 1742.

Scott C. Virgil

Massachusetts Institute of Technology, Cambridge, MA, USA

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