Prepn. of diamines by hydrogenation of unsatd. CO-contg. nitriles - in presence of ammonia

摘要

Diamines (I) are prepared by hydrogenation of alpha,beta-unsatd. nitriles with CO-groups (II), in the presence of at least a stoichiometric amt. of ammonia, and a hydrogenation catalyst: H2N-(CH2)3-C(CH3)2-CH2)-CHR1-CHR2-NH2 (I) NC-CH2-CH2-C(CH3)2-CH=CR1-CR2=O (II) where R1 and R2 = H, alkyl, cycloalkyl, or aryl, or together may form a carbon ring. The reaction is pref. carried out in two stages. In the first stage, nitrile (II) is hydrogenated at -20 to +70 deg.C. in the absence of ammonia to hydrogenated the CO group. Hydrogenation to diamine (I) is then completed at 70-130 deg.C. in the presence of ammonia.