Patent ID: 8592632

Claim:
A process for preparing at least one cyclic diamine selected from a diamine of the formulae (Ia), (Ib), (Ic) or (Id) wherein the R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R a , R b radicals are each independently selected from the group consisting of H and alkyl; and where R 1 or R 2 is, or R 1 and R 2 are each, H, said process comprising at least steps (I) to (II): (I) reacting at least one compound selected from a compound of the formulae (IIa) and (IIb) wherein X is a group selected from the group consisting of —CN, —CHO, —CO 2 R c , —C(═O)R b and —CH 2 OH, where R b is selected from the group consisting of H and alkyl, and where R c is independently selected from the group consisting of H and alkyl; with a gas mixture (G) comprising dinitrogen monoxide to obtain at least one compound selected from compounds of the formulae (IIIa), (IIIb), (IIIc) and (IIId) (II) converting the at least one compound obtained in step (I) to at least one compound selected from compounds of the formulae (Ia), (Ib), (Ic) and (Id) by reductive amination.