Chemical Properties
off-white to light yellow-brown powder. Soluble in hot alcohol, hot acetic acid and acetone, insoluble in water.
Uses
4-Nitrophthalic anhydride is used an an intermediate for the synthesis of a benzimidazole PARP inhibitor I (succinate salt) (ABT-472).
Uses
5-Nitrophthalic Anhydride is used in the preparation of phthalic acids as well as compounds with anticonvulsant activities.
Preparation
4-Nitrophthalic anhydride is synthesized by hydrolysis of 4-nitrophthalimide and then dehydration. The 4-nitrophthalimide was added to the sodium hydroxide solution, heated and boiled for 15min. Adjust pH to 6-8 with nitric acid, and add nitric acid to boil for 5 min. Cooling, filtering, the filtrate was extracted with ether, the extract was dried and then the ether was evaporated, that is, 4-Nitrophthalic anhydride crystals were precipitated. Yield 95%.
General Description
Yellow powder.
Air & Water Reactions
Reacts with water. The organic acids produced by this reaction are significantly more soluble in water.
Reactivity Profile
4-Nitrophthalic anhydride reacts exothermically with water. The reactions are usually slow, but might become violent if local heating accelerates their rate. Acids accelerate the reaction with water. Incompatible with acids, strong oxidizing agents, alcohols, amines, and bases.
Fire Hazard
Flash point data for 4-Nitrophthalic anhydride are not available, however 4-Nitrophthalic anhydride is probably combustible.
Purification Methods
Distil the anhydride in a vacuum and/or recrystallise it from *C6H6 or Et2O/pet ether. Dry it in vacuo. It forms addition compounds with anthracene (m 118o), and phenanthrene (m 96o). [Beilstein 17 III/IV 6150, 17/11 V 267.]
Precautions
Moisture Sensitive. Store away from strong bases and oxidizing agents. Incompatible with water, bases, strong acids and oxidizing agents.