Triethylamine → 4-Chloro-6-iodoquinazoline

Participants

Reaction Steps

In a 100 mL-volume glass vessel equipped with a stirrer, a thermometer and a reflux condenser were placed 20.0 g (73.5 mmol) of 6-iodoquinazolin-4-one, 13.5 g (88.2 mmol) of phosphorus oxychloride, and 60 mL of toluene in a nitrogen atmosphere. While the mixture was stirred at room temperature, 8.92 g (88.2 mmol) of triethylamine was slowly added. The resulting mixture was heated to 75° C., and the reaction was carried out for 2 hours. After the reaction was complete, the reaction mixture was cooled to 0° C. and stirred for one hour. Thus precipitated pale yellow crystalline product of 6-iodo-4-chloroquinazoline was collected by filtration. Subsequently, the crystalline product was placed in 100 mL of aqueous sodium hydroxide (1 mol/L), and the aqueous mixture was stirred for 30 minutes at room temperature. The crystalline product was collected by filtration, washed with 120 mL of water, and dried under reduced pressure, to give 19.3 g (isolated yield: 90%, purity 99.3% in terms of area percentage determined by high performance liquid chromatography) of 6-iodo-4-chloroquinazoline as a yellowish crystalline product.

Provenance & Evidence