Nitric Acid → 4-Iodo-3-nitrothioanisole

Participants

Reaction Conditions

Reaction Steps

A flask was charged with 10 g of 4-iodothioanisole and 5.5 mL of dimethylsulfate and warmed to ca. 90° C. for 10 min. The resulting solution was dissolved in conc. sulfuric acid (30 mL) and cooled to ca. 0-4° C., whereupon it was treated, with extreme caution, slowly with conc. HNO3 (ca. 2 mL) while maintaining the reaction temperature below 4° C. After stirring it for ca. 10 min, the reaction mixture was stirred at ca. 90° C. for ca. 3 d. The reaction was monitored with HPLC, TLC, and LC-MS, and if needed, smaller portions of nitric acid were added to the reaction mixture to force it to completion. Use of fuming sulfuric acid is also helpful. After the complete consumption of the aromatic starting material, the reaction mixture was cooled, poured over crushed ice, treated with 30% aq. perchloric acid at 4° C. The light colored precipitate was filtered, washed thoroughly with water, and dried under vacuum. The perchlorate salt was stirred with saturated aq. NaCl solution at 95° C. for 3-6 h. Upon cooling to room temperature, the precipitate was filtered, washed thoroughly with water to get rid of any inorganic salts, and dried under vacuum to obtain 4-iodo-3-nitrothioanisole in >80% yield.

Provenance & Evidence