# US 5,703,262 A · Process for the preparation of dithiophosphoric acids

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- Number: US 5,703,262 A
- Document ID: US5703262A
- Status: Granted
- Kind: A
- Application number: 07/573,209
- Filed: 1993-04-06
- Granted: 1997-12-30
- Earliest claimed: 1993-04-06
- Assignees: Exxon Chemical Patents Inc.
- Inventors: Terence Colclough; Philip Skinner; John Derek Woollins; Paul Thomas Wood
- Web page: https://patentgrep.com/patent/US5703262A

## CPC

- C10M 137/105: {not containing metal}
- C07F 9/17: with hydroxyalkyl compounds without further substituents on alkyl
- C07F 9/18: with hydroxyaryl compounds
- C10M 2205/06: containing conjugated dienes
- C10M 2209/084: Acrylate; Methacrylate
- C10M 2223/045: Metal containing thio derivatives
- C10N 2010/04: Groups 2 or 12
- C10M: LUBRICATING COMPOSITIONS (well drilling compositions C09K8/02); USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION (mould release, i.e. separating, agents for metals B22C3/00, for plastics or substances in a plastic state, in general B29C33/56, for glass C03B40/02; textile lubricating compositions D06M11/00, D06M13/00, D06M15/00; immersion oils for microscopy G02B21/33)
- C07F: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM (metal-containing porphyrins C07D487/22)
- C10N: INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS

## Abstract

Dithiophosphoric acids are advantageously produced by reaction of an alcohol or phenol with phosphorus sesquisulphide in the presence of sulphur, preferably at the reflux temperature of the alcohol used.

## Claims

### Claim 1

A process for preparing a dithiophosphoric acid of the formula (RO).sub.2 PS.sub.2 H, wherein R is derived from an aliphatic alcohol or phenol, comprising preparing a reaction mixture containing phosphorus sesquisulphide, sulphur, and one or more aliphatic alcohol or phenol wherein the overall atomic ratio of sulphur to phosphorus is at least 2.5 to 1, and refluxing the mixture at a temperature in the range of 85.degree. to 150.degree. C.

### Claim 2 (depends on 1)

The process according to claim 1 in which the alcohol is a nonhydric or polyhydric straight or branched aliphatic alcohol of 3 to 10 carbon atoms, or an alkyl phenol having up to 20 carbon atoms in the alkyl residue.

### Claim 3 (depends on 2)

The process according to claim 2 in which the alcohol is n-butanol or 2-ethylhexan-1-ol.

### Claim 4 (depends on 2, 3)

The process according to claim 2 or 3 in which the reaction is effected at the reflux temperature of the alcohol used.