Patent · US Expired

Preparation of sulphonated aromatic esters

US4788316A · kind A · utility

12Cited by
9References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 1986
Grant dateNov 29, 1988
Priority date
Expiry dateDec 16, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C309/00
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for preparing sulphonated aromatic esters of the group consisting of substituted or unsubstituted sulphonato-phenyl carboxylates and sulphonato-phenyl carbonates is disclosed, comprising the steps of: PA1 (1) preparing the unsulphonated aromatic ester; PA1 (2) sulphonating said unsulphonated aromatic ester; and PA1 (3) neutralizing the acid-sulphonated aromatic ester in a non-aqueous organic solvent with an alkali metal, earth alkali metal or ammonium carboxylate in an amount in excess over the amount needed to neutralize the sulphonic acid group(s) and any free or complexed SO.sub.3 present in the product mixture from the sulphonation reaction. Preferred neutralizing agent is sodium acetate; preferred solvents are acetic acid or glyme and diglyme.

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