# US 4,391,979 A · Process for the preparation of (2-amino-thiazol-4yl)-acetic acid hydrochloride

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

- Number: US 4,391,979 A
- Document ID: US4391979A
- Status: Granted
- Kind: A
- Application number: 06/227,489
- Filed: 1981-01-22
- Granted: 1983-07-05
- Earliest claimed: 1980-02-18
- Assignees: Lonza Ltd.
- Inventors: Alfred Huwiler; Leander Tenud
- Web page: https://patentgrep.com/patent/US4391979A

## CPC

- C07D 277/40: Unsubstituted amino or imino radicals
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)

## Abstract

Process for the simplified preparation of (2-aminothiazol-4-yl)-acetic acid hydrochloride in light-stable form, in high purity and in good yields, by the reaction of thiourea with 4-chloroacetoacetyl chloride.

## Claims

### Claim 1

Process for the preparation of (2-aminothiazol-4-yl)-acetic acid hydrochloride comprising suspending thiourea in water, adding 4-chloroacetoacetyl chloride, which is dissolved in a chlorohydrocarbon, to the suspension at a temperature of 5.degree. to 10.degree. C., and then completing the reaction at a temperature of 25.degree. to 30.degree. C., said (2-aminothiazol-4-yl)-acetic acid hydrochloride being in light-stable form, having a high degree of purity, and being stable both in solution and as a solid.

### Claim 2 (depends on 1)

The process as claimed in claim 1 wherein the chlorohydrocarbon is methylene chloride.

### Claim 3 (depends on 1, 2)

The process as claimed in claim 1 or claim 2 wherein the 4-chloroacetoacetyl chloride, dissolved in the chlorohydrocarbon, is added to the suspension at the rate at which it is consumed.

### Claim 4 (depends on 3)

The process as claimed in claim 3 wherein a 4-chloroacetoacetyl chloride solution is used which has been obtained by chlorinating diketene in the chlorohydrocarbon at a temperature of -10.degree. to -25.degree. C.

### Claim 5 (depends on 1)

The process as claimed in claim 1 wherein the chlorohydrocarbon is carbon tetrachloride, chloroform or 1,2-dichloroethane.

### Claim 6 (depends on 1)

The process as claimed in claim 1 wherein 3 to 50 moles of chlorohydrocarbon are used per mole of 4-chloroacetoacetyl chloride.

### Claim 7 (depends on 1)

The process as claimed in claim 1 wherein a 4-chloroacetoacetyl chloride solution is used which has been obtained by chlorinating diketene in the chlorohydrocarbon at a temperature of -10.degree. to -25.degree. C.

### Claim 8

Process for the preparation of (2-aminothiazol-4-yl)-acetic acid hydrochloride consisting of suspending thiourea in water, adding 4-chloroacetoacetyl chloride, which is dissolved in a chlorohydrocarbon, to the suspension at a temperature of 5.degree. to 10.degree. C., and then completing the reaction at a temperature of 25.degree. to 30.degree. C., said (2-aminothiazol-4-yl)-acetic acid hydrochloride being in light-stable form, having a high degree of purity, and being stable both in solution and as a solid.

### Claim 9 (depends on 1)

(2-Aminothiazol-4-yl)-acetic acid hydrochloride prepared by the process of claim 1, said (2-aminothiazol-4-yl)-acetic acid hydrochloride being in light-stable form, having a high degree of purity, and being stable both in solution and as a solid.

### Claim 10 (depends on 8)

(2-Aminothiazol-4-yl)-acetic acid hydrochloride prepared by the process of claim 8, said (2-aminothiazol-4-yl)-acetic acid hydrochloride being in light-stable form, having a high degree of purity, and being stable both in solution and as a solid.