The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 24, 1992
Filed:
Mar. 09, 1992
Klaus Hutchmacher, Gelnhausen, DE;
Hermann Schmitt, Rodenbach, DE;
Degussa AG, , DE;
Abstract
The invention relates to bis(3-cyano-3,5,5-trimethylcyclohexylidene)-azine (=IPN-azine), a method of its preparation by reacting 1,3,3-trimethyl-5-oxocyclohexane carbonitrile (=IPN) with a source for hydrazine in a molar ratio of essentially 2 to 1 in the presence of a solvent and to a method for the further processing of the IPN-azine to 3-(aminomethyl)-3,5,5-trimethylcyclohexyl amine (isophorone diamine=IPDA) by means of a hydrogenating azine splitting with hydrogen in the presence of an organic solvent, ammonia and of a catalytic system from the series (a) of a cobalt- or nickel-containing Raney catalyst and of a cocatalyst from the series of salts of the elements aluminum, cobalt, nickel, yttrium, lanthanum, cerium, Ru, Rh, Pd, Ir and Pt or of carrier-supported noble metals from the series Ru, Rh, Pd, Ir, Pt or b) of a carrier-supported Ru-, Pd- or Pt catalyst at a pressure of 3 to 30 MPa and a temperature of 50.degree. to 150.degree. C. The method of the invention concerning IPN-azine makes it possible to obtain IPDA from IPN in high yield and purity and avoids disadvantages of the previously known reductive amination of IPN.