Patent · US Expired

Process for preparing substituted phthalic anhydrides

US4560773A · kind A · utility

15Cited by
3References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 16, 1984
Grant dateDec 24, 1985
Priority date
Expiry dateApr 16, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C51/567
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for preparing substituted phthalic anhydrides, e.g. 4-methylphthalic anhydride, in which the Diels-Alder addition product of a conjugated diene, e.g. isoprene, and maleic anhydride is reacted with bromine in the presence of a catalytic quantity of an acid acceptor. Typical catalytic acid acceptors include dimethylformamide and pyridine.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.