| abstract |
A process for the preparation of a 2,2-disubstituted pentane-1,5-diamine of the formula I ##STR1## where R 1 and R 2 , independently of one another, are C 1 - to C 10 -alkyl or C 2 - to C 10 -alkenyl or together are a C 4 - to C 7 -alkylene chain which is unsubstituted or monosubstituted to pentasubstituted by C 1 - to C 4 -alkyl, from a 2,2-disubstituted 4-cyanobutanal of the formula II ##STR2## where R 1 and R 2 are as defined above, comprises, in two spatially separate reaction spaces, n a) reacting the 4-cyanobutanal of the formula II, in a first reaction space, with excess ammonia on an acidic heterogeneous catalyst at from 20° to 150° C. and at from 15 to 500 bar, and n b) hydrogenating the resultant reaction product, in a second reaction space, using excess hydrogen in the presence of excess ammonia on a catalyst containing cobalt, nickel, ruthenium and/or another noble metal, if desired with a basic component or on a basic or neutral carrier, at from 60° to 150° C. and at from 50 to 500 bar. |