Hydrochloric Acid → 2-Acetoxy-3-methyl-3-(p-isobutylphenyl)acrylonitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

The toluene solution of the 3-butylglycidonitrile (Preparation E) is treated with dry hydrogen chloride (59.3 ml. of 3.71 N HCl in ether) with stirring for about 4 hours at 45° C. A mixture of 21.1 g. of pyridine, 18.2 ml. of acetic anhydride and 38.5 ml. of triethyl amine is then added and the reaction mixture is stirred at 75° C. for about 17 hours. The reaction mixture is then cooled, washed with 2 N hydrochloric acid (2 × 160 ml.) and then with 100 ml. of water. The intermediate 2-acetoxy-3-butylacrylonitrile (2-acetoxy-2-heptenonitrile) (VI) thus obtained can if desired be isolated by drying and concentrating the toluene solution or alternatively, the toluene solution is mixed with 61 ml. of water, 24 ml. of acetone and 48 ml. of aqueous 50% sodium hydroxide solution and stirred at about 50° C. overnight to give the sodium salt of hexanoic acid (III). The reaction mixture is then cooled and the two phases are separated. The toluene phase is washed with 10 ml. of 5% aqueous sodium hydroxide solution. The alkaline phase and wash are combined and backwashed with 25 ml. of toluene. The alkaline phase is acidified with 12 N sulfuric acid and extracted with Skellysolve B hexanes, (2 × 50 ml.). The hexane extracts are combined and dried over anhydrous sodium sulfate; the solvent is removed and the product distilled under vacuum to give hexanoic acid (IV).

Herkunft & Nachweise