To produce the subject compound industrially useful as a raw material substance for polyamides and polyurethanes by carrying out the reducing aminating reaction of a dialdehyde in the presence of a hydrogenating catalyst, hydrogen and ammonia, adding a monoamine and hydroxylamine to a crude reactional solution and distilling the resultant crude reactional solution.
The reducing aminating reaction of a dialdehyde (e.g. a straight- chain aliphatic dialdehyde such as butanedial or a branched chain aliphatic dialdehyde such as 2-methyloctanedial) used as a starting raw material is carried out in the presence of a hydrogenating catalyst (e.g. Raney nickel or Raney cobalt), water and ammonia to provide a crude reactional solution containing a diamine such as 1,9-nonanediamine, 2-methyl-1,8-octanediamine or a mixture thereof. A primary monoamine separable from the diamine by distillation (e.g. octylamine or decylamine) or hydroxylamine or both are then added to distill the resultant crude reactional solution to thereby afford the diamine.
NAGAREDA KATSUSHI
SUZUKI SHIGEAKI
