Reaction of Active Indium with Iodine

Sublimed iodine (1.27 g, 5 mmol) was added to activated indium (prepared from 2.21 g of InCls and 1.17 g of potassium) in xylene (25 ml). After refluxing for 30 min, the reaction was complete. The red indium monoiodide was collected by filtration, washed with water to remove the alkali salts, and dried under reduced pressure. The product analyzed correctly for Ini (Calcd. In, 47.50 Found In 46.80, 47.91). The indium was determined by EDTA titration using 4-(2-pyridylazo) resorcinol as indicator or atomic absorption spectroscopy. 

All air-sensitive compounds were manipulated in an inert atmosphere box (Kewaunee Model 2C1982) equipped with a recirculation system to remove moisture and oxygen. 

Anhydrous indium trichloride (ultrapure) was obtained from Alla. Dimethylmercury, diphenylmercury, and ditolylmercury were obtained from Eastman and were used without fruther purification. Potassium (purified) and sodium were obtained from Baker and cleaned under hexane just prior to use. 

Xylene (Baker) was distilled under argon over NaAlH4 through 60 cm glass helix packed column. Benzene (Baker) was distilled over L1A1H4. 

The following procedure for carrying out these reactions is representative of the general technique. InCls (4.41 g, 20 mmol) was placed in a 100 ml round bottomed flask with a side arm equipped with a septum cap in a dry box, and then freshly distilled solvent (25 ml) was added and followed by adding freshly cut potassium (2.34g, 60 mmol) or sodium (1.38 g, 60 mmol) into the flask under argon. The flask was connected with a water condenser, and then the mixture was heated to reflux and stirred with a magnetic stirrer. 

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