Formaldehyde → 6-Methoxy-1-phenyl-1,2-dihydro-4H-3,1-benzoxazin-4-one

Participants

Reaction Steps

A mixture of 15.0 g (0.062 mole) of 5-methoxy-2-(phenylamino)benzoic acid and 75 ml of 37% aqueous formaldehyde solution in 75 ml of ethanol was heated on the steam bath for 75 minutes. The mixture was cooled and added to 400 g ice/water. The crude oxazine product was filtered, stirred in 75 ml of 5% aqueous sodium bicarbonate, and refiltered to yield 13.0 g (83% yield) of the product, mp 99.5°-101° C. A sample recrystallized from hexane was analytically pure, mp 100°-102° C.

Provenance & Evidence