Hydrochloric Acid → 4-Methyl-5-iodosaccharin

Participants

Reaction Conditions

Reaction Steps

A mixture of 205 ml of glacial acetic acid, 160 ml of water and 40 ml of conc. HCl is initially taken and 23.4 g (0.11 mol) of 4-methyl-5-amino-1,1,3-trioxo-2,3-dihydro-1λ6 benz[d]isothiazole are introduced with stirring at 15°-20° C. 7.9 g (0.115 mol) of sodium nitrite are added dropwise to the resulting suspension at 5°-10° C. and it is stirred at 5° C. for 30 min. The diazonium salt, which is present as a suspension, is then added dropwise in portions to a solution of 19.1 g (0.115 mol) of potassium iodide in 170 ml of water which is warmed to 50° C., nitrogen being formed. After cooling to room temperature, the deposited product is isolated by filtering off with suction, washed with water and dried under reduced pressure at 50° C. 32.5 g (0.1 mol=91% of theory) of a solid of m.p.: 257°-258° C. are obtained. A combustion analysis gave an iodine content of 38.5% (theory 39.3%).

Provenance & Evidence