Reaction LXXXIX.—Hydrolysis of Nitriles to Amides

Reaction LXXXIX. Hydrolysis of Nitriles to Amides. (B., 18, 355.)— When nitriles are heated with acids or alkalis they are hydrolysed to the corresponding acids passing intermediately through the amides. It is possible only in a few instances (e.g., oxamide) to stop the hydrolysis at this intermediate stage, unless alkaline hydrogen peroxide is employed, when the amide is obtained in almost theoretical yield. Both methods of hydrolysis are illustrated in the following preparations. 

25 gms. (1 mol.) of crystallised copper sulphate are dissolved in 75 c.cs. of water in a distilling flask heated on a water bath, and a warm solution of 13 gms. (2 mols.) of 98% potassium cyanide in 25 c.cs. of water is added (caution cyanogen is extremely poisonous). The evolved cyanogen is led into 20 c.cs. of cold cone, hydrochloric acid. When all the cyanide has been added, the second equivalent of cyanogen is expelled by adding, in the same way, a solution of 16 gms. (1 mol.) of ferric chloride in 20 c.cs. of water. Oxamide separates out, provided the hydrochloric acid is kept quite cool. It is washed with water. 

—50% theoretical (4-5 gms.). White crystalline solid partly sublimes on heating, but for the most part decomposes sparingly soluble in water and in alcohols. (B., 18, 355.) 

20 gms. (1 mol.) of benzonitrile are added to 300 c.cs. (excess) of 3% (10 volumes) aqueous hydrogen peroxide containing 5 c.cs. of 2N caustic soda. The mixture is warmed on a water bath to 40°, and then shaken in an uncorked bottle until the oil has completely disappeared. The precipitate which forms is filtered off at the pump, and recrystallised from alcohol or hot water. 

Reaction XC. Hydrolysis of the Disaccharides. (J. pr., [2] 2, 1, 245 B., 13, 1761 28, 1429.)—When the disaccharides, and in fact all the glucosides, are heated with mineral acids, they are hydrolysed into their component monosaccharides or into their component monosaccharides and alcohols. 

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