O-Toluidine → Methaqualone

Participants

Reaction Steps

The isatoic anhydride and acetic anhydride were reacted under the condition described for the preparation of 2-methyl-4H-3,1-benzoxazine-4-one. The pyridine was distilled from the reaction mixture under reduced pressure. The crude reaction product was taken up in 100 ml of o-xylene and placed in a 200 ml one-necked flask equipped with a Dean-Stark trap and a reflux condenser. The o-toluidine was added to the xylene solution. The reaction mixture was heated to reflux for 4 hours. 1.8 ml of water was collected in the Dean-Stark trap. The xylene was removed from the reaction product by distillation under reduced pressure. The resulting residue was crystallized twice from methanol to give 16 parts (64% yield) of 2-methyl-3-(o-tolyl)-quinazoline-4 (3H)-one with m.p. 113°-115° C. The reaction product was characterized by melting point, IR and NMR.

Provenance & Evidence