# US 5,344,966 A · Hydrogenation of phenylphosphonic acid

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

- Number: US 5,344,966 A
- Document ID: US5344966A
- Status: Granted
- Kind: A
- Application number: 08/118,501
- Filed: 1992-11-05
- Granted: 1994-09-06
- Earliest claimed: 1987-12-16
- Assignees: Imperial Chemical Industries PLC
- Inventors: Michael Yelland
- Web page: https://patentgrep.com/patent/US5344966A

## CPC

- C07F 9/383: {Cycloaliphatic acids}
- C07F: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM (metal-containing porphyrins C07D487/22)

## Abstract

A cycloalkyl phosphorus compound is obtained by the catalytic hydrogenation of a substituted or unsubstituted aryl phosphonic acid using a heterogeneous catalyst which is a Group VIII metal on carbon. The hydrogenation is preferably effected in water. The catalyst can be ruthenium or carbon. When phenylphosphonic acid is used as the starting material, a yield of about 95% of essentially pure cyclohexylphosphonic acid can be obtained.

## Claims

### Claim 1

A process for producing a cycloalkyl phosphonic acid which comprises hydrogenating a phenyl phosphonic acid optionally substituted with an amino-group or at least one alkyl group containing from 1 to 6 carbon atoms in the presence of a liquid medium in which the phosphonic acid reaction product is soluble under the reaction conditions and which is not reactive with the phosphonic acid and a heterogeneous catalyst which is a Group VIII metal on carbon.

### Claim 2 (depends on 1)

The process of claim 1 wherein the liquid medium is water.

### Claim 3 (depends on 1)

The process of claim 1 wherein the heterogeneous catalyst is ruthenium on carbon.

### Claim 4 (depends on 1)

The process of claim 1 wherein the catalyst contains at least 1%, and not more than 10% by weight of the Group VIII metal.

### Claim 5 (depends on 1)

The process of claim 1 wherein the catalyst is used in an amount of from 1% up to 10% by weight of the substituted or unsubstituted phenyl phosphonic acid.

### Claim 6 (depends on 1)

The process of claim 1 which is effected at a temperature of at least 50.degree. C. and not in excess of 200.degree. C.

### Claim 7 (depends on 1)

The process of claim 1 which is effected at a hydrogen pressure of at least 0.2 MNm.sup.-2 absolute and not exceeding 10 MNm.sup.-2.

### Claim 8 (depends on 1)

The process of claim 1 wherein the Group VIII metal is selected from the group consisting of platinum, palladium and ruthenium.

### Claim 9

A process which comprises hydrogenating a phenyl phosphonic acid optionally substituted with an amino-group or at least one alkyl group containing from 1 to 6 carbon atoms in the presence of water and a heterogeneous catalyst which is a Group VIII metal on carbon wherein the catalyst contains at least 1% and not more than 10% by weight of the group VIII metal.

### Claim 10 (depends on 1)

The process of claim 1 in which the phenylphosphonic acid is optionally substituted with at least one alkyl group containing from 1 to 6 carbon atoms.

### Claim 11

A process for producing cyclohexyl phosphonic acid comprising hydrogenating phenylphosphonic acid in the presence of a liquid medium in which the phosphonic acid reaction product is soluble under the reaction conditions and which is not reactive with the phosphonic acid and a heterogeneous catalyst which is a Group VIII metal on carbon.