Process for the preparation of acetic acid derivatives
US4127604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1977 |
| Grant date | Nov 28, 1978 |
| Priority date | — |
| Expiry date | May 25, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C53/128
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for the preparation of di-n-propyl acetic acid of formula: ##STR1## and its non-toxic alkali and alkaline earth metal salts whereby in a single stage, sodium n-propylate in n-propanol medium is added to a reaction medium formed of a cyanacetic ester of general formula: ##STR2## in which R represents an alkyl radical having from 1 to 4 carbon atoms, and n-propyl bromide or iodide, the alkylation reaction taking place under reflux, the crude ester obtained is saponified with a 10 to 20% solution of sodium or potassium hydroxide, the salt thus obtained is acidified with a strong acid, to give the crude di-n-propyl cyanacetic acid, which is decarboxylated by heating at a temperature between 140.degree. and 190.degree. C, to provide the di-n-propyl acetonitrile, the di-n-propyl acetonitrile obtained is hydrolysed by means of an aqueous solution of 75 to 80% sulphuric acid at a temperature of 80.degree.-140.degree. C to give the crude di-n-propyl acetamide, which is hydrolyzed by means of an aqueous solution of 75-80% sulphuric acid at a temperature of 40.degree.-80.degree. C in the presence of sodium nitrite, to provide di-n-propyl acetic acid, which is caused to react, if so de…
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