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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1855931Generated: November 3, 2026

N-Phenylphthalimide → Phthalic Anhydride

https://huagongshe.com/reaction/1855931

Reaction equation

Participants

RoleNameHCIDCharge
ReactantN-PhenylphthalimideHCID 68215—
ReactantMaleic AcidHCID 444266—
SolventWaterHCID 962—
ProductPhthalic AnhydrideHCID 6811—
ProductN-PhenylmaleimideHCID 13662—

Reaction Conditions

Temperature180 °C

Reaction Steps

A mixture of 2.32 parts of maleic acid, 2.23 parts of N-phenyl phthalimide and 20 parts of water is heated under sealed conditions for 2 hours at 180° C. The reaction mixture is then allowed to cool to ambient conditions and distilled under vacuum. Maleic anhydride is initially recovered followed by phthalic anhydride and N-phtnyl maleimide. There is obtained a yield of 16% by weight of phthalic anhydride and 14.1% by weight of N-phenylmaleimide.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04217281
Source datasetuspto-grants-1980_08
ORD IDord-7cec22c7fb5b4678ac8e6c90710b6c2d
Source noteuspto-grants-1980_08