Syntheses and crystal structure of 4-[(pyridin-3-yl)diazen-yl]morpholine and 1-[(pyridin-3-yl)diazen-yl]-1,2,3,4-tetra-hydro-quinoline

Abstract

Two new heterocyclic 1,2,3-triazenes were synthesized by diazo-tation of 3-amino-pyridine following respectively by coupling with morpholine or 1,2,3,4-tetra-hydro-quinoline. 4-[(Pyridin-3-yl)diazen-yl]morpholine (I), C₉H₁₂N₄O, has monoclinic P2₁/c symmetry at 100 K, while 1-[(pyridin-3-yl)diazen-yl]-1,2,3,4-tetra-hydro-quinoline (II), C₁₄H₁₄N₄, has monoclinic P2₁/n symmetry at 100 K. These 1,2,3-triazene derivatives were synthesized by the organic medium method by coupling reactions of 3-amino-pyridine with morpholine and 1,2,3,4-tetra-hydro-quinoline, respectively, and characterized by ¹H NMR, ¹³C NMR, IR, mass spectrometry, and single-crystal X-ray diffraction. The mol-ecule of compound I consists of pyridine and morpholine rings connected by an azo moiety (-N=N-). In the mol-ecule of II, the pyridine ring and the 1,2,3,4-tetra-hydro-quinoline unit are also connected by an azo moiety. The double- and single-bond distances in the triazene chain are comparable for the two compounds. In both crystal structures, the mol-ecules are connected by C-H⋯N inter-actions, forming infinite chains for I and layers parallel to the bc plane for II.

Keywords: 1,2,3,4-tetra­hydro­quinolein; 1,2,3-triazenes; crystal structure; morpholine; pyridine.

Figure 1

A view of the title compound I, showing the atom-numbering scheme. Displacement ellipsoids are plotted at the 30% probability level.

Figure 2

A view of the title compound II, showing the atom-numbering scheme. Displacement ellipsoids are plotted at the 30% probability level.

Figure 3

Infinite chains of compound I parallel to the a axis.

Figure 4

Layers of compound II parallel to the bc plane.

Figure 5

Reaction scheme.