# US 5,703,274 A · Process for the preparation of 5-hydroxyisophtalic acids

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,703,274 A
- Document ID: US5703274A
- Status: Granted
- Kind: A
- Application number: 08/621,533
- Filed: 1996-03-26
- Granted: 1997-12-30
- Earliest claimed: 1995-03-27
- Assignees: Bromine Compounds Ltd.
- Inventors: Mark Gelmont; Joseph Bercovici; Jakob Oren
- Web page: https://patentgrep.com/patent/US5703274A

## CPC

- C07C 51/367: by introduction of functional groups containing oxygen only in singly bound form
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS

## Abstract

A process for the preparation of 5-hydroxyisophthalic acid (5-HIPA) that comprises hydrolyzing a starting material chosen from among 5-bromoisophthalic acid (5-BIPA), mixtures of 5-BIPA and dibromoisophthalic acid isomers, and salts of thereof in an aqueous alkaline solution, in the presence of a catalytically effective amount of a copper compound catalyst and in a temperature range of between 100.degree. and 270.degree. C.

## Claims

### Claim 1

A process for the preparation of 5-hydroxyisephthalic acid (5-HIPA) that comprises hydrolyzing a starting material chosen from among 5-bromoisophthalic acid (5-BIPA), mixtures of 5-BIPA and dibromoisophthalic acid isomers, and salts of thereof in an aqueous alkaline solution, in the presence of a catalytically effective amount of a copper compound catalyst and in a temperature range of between 100.degree. and 270.degree. C.

### Claim 2 (depends on 1)

A process according to claim 1, wherein the hydrolysis is carried out under autogenous pressure.

### Claim 3 (depends on 1)

A process according to claim 1, wherein the alkali in the aqueous solution is selected from among the hydroxides, oxides and carbonates of sodium and potassium or mixtures thereof.

### Claim 4 (depends on 1)

A process according to claim 1, in which the alkalis of the aqueous solution are used in an amount of more than 4 equivalents of the halogen atom in the starting material.

### Claim 5 (depends on 1)

A process according to claim 1, wherein the catalyst comprises one or more compounds of the formula:
Cu(n)R(m), in which:
R is --O, --OH or the anion of an inorganic or organic acid;
n is 1 or 2; and
m is 0, 1 or 2.

### Claim 6 (depends on 1)

A process according to claim 1, in which copper compound catalysts may be used either individually or in mixtures in an amount of between 0.1-20% by mole.

### Claim 7 (depends on 5)

A process according to claim 5, wherein the catalyst is chosen from among Cu, CuCl, CuCl.sub.2, CuBr.sub.2, Cu.sub.2 O, Cu(OH).sub.2, CuSO.sub.4, and Cu(OAc).sub.2.

### Claim 8 (depends on 1)

A process according to claim 1, wherein the temperature range is 100.degree.-270.degree. C.

### Claim 9 (depends on 1)

A process according to claim 1, comprising preparing the 5-BIPA by bromination of isophthalic acid (IPA).

### Claim 10 (depends on 1)

A process according to claim 1, wherein the salts are alkali salts.

### Claim 11 (depends on 6)

A process according to claim 6, in which copper compound catalysts may be used either individually or in mixtures in an amount of between 1.0-5.0% by mole.

### Claim 12 (depends on 8)

A process according to claim 8, wherein the temperature range is 140.degree.-200.degree. C.