Ammonia → Phthalamic acid

Participants

Reaction Steps

With vigorous stirring, concentrated ammonia solution (900 ml, S.G. 0.9) was treated portionwise with phthalic anhydride (600 g, 4.0 moles) over a period of 11/2 hrs. After the reaction mixture had cooled to room temperature, the precipitated ammonium phthalamate was filtered, then dissolved in the minimum of water. When this solution was acidified to pH 2, phthalamic acid began to crystalize, M.P. 132°-6°.

Provenance & Evidence