摘要 |
A process is provided for the preparation of p-hydroxy-benzyl-nitriles starting from the corresponding p-hydroxy-benzaldehyde, first reducing the p-hydroxy-benzaldehyde to the p-hydroxy-benzyl amine, a primary amine, with hydrogen in the presence of aqueous ammonia, preferably with the addition of small amounts of lower alkyl alcohol; and Raney nickel catalyst at low pressure; and then converting the amine to the p-hydroxy-benzyl-nitrile by reaction with sodium cyanide at elevated temperature; the first stage, the reduction, is applicable also to o- and m-hydroxy benzaldehydes.
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