Preparation of cyclic amines
First Claim
1. A process for the preparation of aromatic amines of the formula I ##STR4## where R1, R2, R3, R4 and R5 are each hydrogen, C1 -C12 -alkyl or C3 -C12 -cycloalkyl, from aliphatic amines of the formula II ##STR5## where R1, R2, R3, R4 and R5 have the abovementioned meanings, at from 150°
- to 300°
C. and from 0.01 to 50 bar in the presence of a heterogeneous catalyst, wherein the heterogeneous catalyst consists of from 30 to 100% by weight ofa) palladium on oxides of the rare earth elements or on oxides of metals of Group IVb orb) platinum/palladium mixtures on alumina or oxides of the rare earth element or oxides of metals of Group IVband from 0 to 70% by weight of alkali metal or alkaline earth metal oxide.
2 Assignments
0 Petitions
Accused Products
Abstract
A process for the preparation of a phenyl amine which may be substituted by alkyl or cycloalkyl in which the corresponding cyolohexylamine is reduced at temperatures of 150° to 300° C. and pressures of 0.01 to 50 bar in the presence of a heterogeneous dehydrogenation catalyst consisting essentially of palladium or a palladium/platinum mixture supported on carrier consisting of the oxides of rare earth metals and and metals of Group IVb of the Periodic Table of Elements, with the proviso that the palladium/platinum mixture may also be supported on an alumina carrier. The cyclohexylamine reactant can be advantageously prepared by reacting the corresponding phenol with ammonia and hydrogen at 100° to 250° C. in the presence of the same heterogeneous catalyst as a preliminary step to provide a two stage process using the same catalyst in both stages.
9 Citations
8 Claims
-
1. A process for the preparation of aromatic amines of the formula I ##STR4## where R1, R2, R3, R4 and R5 are each hydrogen, C1 -C12 -alkyl or C3 -C12 -cycloalkyl, from aliphatic amines of the formula II ##STR5## where R1, R2, R3, R4 and R5 have the abovementioned meanings, at from 150°
- to 300°
C. and from 0.01 to 50 bar in the presence of a heterogeneous catalyst, wherein the heterogeneous catalyst consists of from 30 to 100% by weight ofa) palladium on oxides of the rare earth elements or on oxides of metals of Group IVb or b) platinum/palladium mixtures on alumina or oxides of the rare earth element or oxides of metals of Group IVb and from 0 to 70% by weight of alkali metal or alkaline earth metal oxide. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
- to 300°
Specification