Tetramethylammonium Dichloroiodate I

To a solution of 21.9 g. of tetramethylammonium chloride (0.20 mol) in 400 ml. of glacial acetic acid is added 32.5 g. of iodine(I) chloride10 (0.20 mol). The yellow crystals which precipitate are removed by filtration and washed with carbon tetrachloride. The yield is 51.0 to 53.0 g. (94 to 97%). The product (m.p. 237 to 238°) can be recrystallized from isopropyl alcohol containing a small quantity of iodine(I) chloride. The final melting point is the reported11 value of 226 to 230°.J Anal. Calcd. for (CH3)4NIC12 C, 17.66 H, 4.42 N, 5.15 iodometric equivalent, 59.3. Found C, 17.71 H, 4.38 N, 5.38 iodometric equivalent, 59.0. 

Erlenmeyer flask is fitted with an inlet tube reaching nearly to the bottom of the flask and an exit tube and is placed in a hood. A solution of 200 g. of tetrabutylammonium iodide512 (0.54 mol) in 1500 ml. of chloroform is placed in the flask. The solution is cooled in an ice-water bath, and tank chlorine which has been passed through a 500-ml. gas-washing bottle containing 250 ml. of 18 M sulfuric acid and a similar empty-bottle spray trap is passed into the solution through the inlet tube. The color 

J The decrease in melting point is due to decomposition on recrystallization. The compound is best used without recrystallizAtion. 

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