Preparation of secondary amines from nitriles

US6525223B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Joachim Pfeffinger · Ludwigshafen, DE
• Michael Hullmann · Bensheim, DE
• Arthur Hohn · Tauberbischofsheim, DE
• Frank Funke · Bischofswerda, DE
• Frank Ohlbach · Mülheim an der Ruhr, DE
• Till Gerlach · Ludwigshafen, DE

Key dates

• Filing date: Dec 27, 2001
• Grant date: Feb 25, 2003
• Expiry date: Dec 27, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C209/48
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Secondary amines of the formula (II)(X—CH2—)2NH  (II)whereX is a C1-20-alkyl, C2-20-alkenyl or C3-8-cycloalkyl group which may be unsubstituted or substituted by C1-20-alkyl, C3-8-cycloalkyl, C4-20-alkylcycloalkyl, C4-20-cycoalkylalkyl, C2-20-alkoxyalkyl, C6-14-aryl, C7-20-alkylaryl, C7-20-aralkyl, C1-20-alkoxy, hydroxy, C1-20-hydroxyalkyl, amino, C1-20-alkylamino, C2-20-dialkylamino, C2-12-alkenylamino, C3-8-cycloalkylamino, arylamino, diarylamino, aryl-C1-8-alkylamino, halogen, mercapto, C2-20-alkenyloxy, C3-8-cycloalkoxy, aryloxy and/or C2-8-alkoxycarbonyl,are prepared by reacting nitriles of the formula (III)X—CN  (III)with hydrogen at from 20 to 250° C. and pressures of from 60 to 350 bar in the presence of an Rh-containing catalyst comprising from 0.1 to 5% by weight, based on the total weight of the catalyst, of Rh on a support to give mixtures of primary amines of the formula (I)X—CH2—NH2  (I)and secondary amines of the formula (II)(X—CH2—)2NH  (II)and returning at least part of the primary amines separated from the mixtures obtained to the reaction.