Hydrogen Peroxide → 3-cyano-6-methyl-5-[4-(methylsulfonyl)phenyl]-2(1H)-pyridinone

Beteiligte Stoffe

Reaktionsschritte

The above 4-(methylsulfonyl)phenyl compound also was prepared from the corresponding 4-(methylsulfinyl)phenyl compound as follows: to a stirred warm solution containing 0.8 g of 3-cyano-6-methyl-5-[4-(methylsulfinyl)phenyl]-2(1H)-pyridinone in 30 ml of glacial acetic acid was added 500 ml tungstic acid and to the resulting stirred solution was added dropwise over a period of 2 minutes a solution containing 0.102 g of hydrogen peroxide in acetic acid (32.97 mg/ml/3.1 ml) and the resulting reaction mixture was stirred at room temperature for 1 hour and then heated occasionally over a period of 1 hour. After tlc analysis indicated a small quantity of methylsulfinyl compound still present, and additional 3 ml of said hydrogen peroxide solution was added and heating as above was continued for 1 hour. The hot reaction mixture was filtered thru diatomaceous earth to remove the tungstic acid, the filter pad washed with warm acetic acid and the filtrate stripped, first in vacuo and then under high vacuum. The remaining solid residue was slurried in about 75 ml of hot absolute ethanol and the mixture cooled slightly. The solid was collected, washed with ethanol and dried at 65° C. in vacuo to yield 0.7 g of 3-cyano-6-methyl-5-[4-(methylsulfonyl)phenyl]-2(1H)-pyridinone, m.p. 311°-313° C.

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