GB328381A - Improvements in the manufacture and production of aliphatic or cyclic primary amines - Google Patents

Abstract

328,381. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). March 11, 1929. Amines; propyl alcohol.-Aliphatic or aromatic primary amines are prepared by treating unsaturated aliphatic or aromatic aldehydes or ketones in the vapour phase and at a raised temperature with hydrogen and ammonia in the presence of an hydrogenating catalyst. The process may be conducted cyclically by circulating the mixture of hydrogen and ammonia., and in order to avoid resinification of the aldehyde or ketone, the vapour of the latter, mixed with fresh hydrogen, is led to the reaction vessel and mixed therein with the preheated circulating mixture of hydrogen and ammonia. Fresh ammonia is also added to the circulating mixture, in accordance with the consumption. The preferred hydrogenation catalysts are those containing a metal of the eighth periodic group and activating additions of difficultly reducible oxides of metals of the fifth and sixth groups. According to the examples, (1) crotonaldehyde, ammonia, and hydogen are passed at 130‹ C. over a catalyst prepared by drying a paste of nickel oxide, cobalt carbonate, and chromic acid solution, applying the powder, together with colloidal silica, on to granular pumice, and then reducing with hydrogen; nbutylamine and some dibutylamine are obtained; (2) acrolein, ammonia, and hydrogen are passed at 125‹ C. over a catalyst prepared by depositing a paste of nickel oxide and colloidal silica on pumice ; and then reducing with hydrogen; n-propylamine and a little propyl alcohol are obtained; (3) cinnamic aldehyde, ammonia, and hydrogen are passed at 150‹ C. over the same catalyst as in example 2, whereby gamma-phenyl-n-propylamine is obtained. Specification 265,960 is referred to.