[CH3:1]CCBr.[I-].[CH2:6]([CH:9]([CH2:12][CH2:13][CH3:14])[C:10]#[N:11])[CH2:7][CH3:8].[OH-:15].[Na+].[OH-:17].[K+].[Na]>>[CH2:6]([C:9]([CH2:12][CH2:13][CH3:14])([C:10]#[N:11])[C:1]([OH:17])=[O:15])[CH2:7][CH3:8]Process for the preparation of di-n-propylacetonitrile of the formula: ##STR5## whereby, (a) sodium n-propylate in n-propanol medium is added to a reaction medium which is formed of a cyanacetate of general formula: ##STR6## 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 at atmospheric pressure, (b) the crude ester obtained is saponified at a temperature between 30° and 70° C. with a 10 to 20% by weight solution of sodium hydroxide or potassium hydroxide in the proportion of 1.25 to 2 mols of sodium or potassium hydroxide per mol of crude ester, the resulting salt is acidified with a strong acid at a temperature not exceeding 40° C., to give crude di-n-propyl cyanacetic acid, (c) which is decarboxylated solely by heating, in the absence of any supplementary agent, at a temperature between 140° C. and 190° C., so as to obtain the di-n-propylacetonitrile.
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