Methyl iodide → 6-chloro-1-methyl-4-phenyl-2(1H)quinazolinone 3-oxide

Participants

Reaction Steps

A mixture of 125 g (0.458 mole) of 6-chloro-4-phenyl-2(1H)quinazolinone 3-oxide, 3,250 ml of N,N-dimethylformamide and 75 g of powdered anhydrous potassium carbonate was heated to 50°. After heating for approximately 30 minutes at this temperature, an increased solubility of the suspended solid due to formation of the potassium salt of I was observed. At this point, 150 g (65.8 ml) of methyl iodide was added dropwise at a fast rate. The reaction with the methyl iodide was somewhat exothermic and caused the pot temperature to rise to 58°. Stirring at 50°-55° was continued for 1 hour. The contents of the flask were cooled and filtered and the solid obtained was thoroughly washed with water. The product, 6-chloro-1-methyl-4-phenyl-2(1H)quinazolinone 3-oxide was obtained in 80% yield (103.2 g), mp 253.5°-254°.

Provenance & Evidence