Maleic Anhydride → Diammonium maleate

Temperature

25 °C

Following the examples of U.S. Pat. No. 4,839,461, a solution of 1.96 g (0.02 mole) maleic anhydride was dissolved in 1 ml water at 50°-60° C. and stirred for 30 minutes while allowing the mixture to cool to 25° C. To this colorless solution at 25° C. was added 2.4g of 30% aqueous solution of ammonium hydroxide (0.022 mol NH3) to give a colorless solution. This solution was boiled to dryness over a period of 30 minutes at approximately 100°-120° C. and 10-20 Tort, to give a white crystalline solid. The solid was tumbled under nitrogen at 100 Torr, at 135°-140°. for 8 hours to give a water insoluble, pinkish-tan brittle glasslike solid weighing 2.7 g. This solid was dissolved in 6.6 g of an aqueous solution containing 0.8 g of sodium hydroxide to form a clear orange solution, pH 7.0, containing 25% solids.

1. customto give a colorless solution
2. waitThis solution was boiled to dryness over a period of 30 minutes at approximately 100°-120° C.
3. custom10-20 Tort, to give a white crystalline solid
4. customwas tumbled under nitrogen at 100 Torr, at 135°-140°
5. customto form a clear orange solution, pH 7.0

ORD record

ord-4108642c9e2b4ea7bd4f5cbb17ec0fec

Source dataset

uspto-grants-1994_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05367047