Syntheses and Single-Crystal X-ray Structures of a Series of Monosubstituted cis,cis-1,3,5-Triaminocyclohexane-Based Complexes

The four triimine compounds cis, cis -1,3,5-tris[( E )-(X)-benzylideneamino]cyclohexane [X = H ( 1 ); 3-hydroxy ( 2 ); 3,5-dimethoxy ( 3 ); 4-acetamido ( 4 )] are synthesized by the condensation of cis, cis -1,3,5-triaminocyclohexane with a substituted aromatic aldehyde. Complexation of these ligands with metal salts ( 1 with Ni, Cu, and Zn salts; 2 and 3 with Cu salts; 4 with a Zn salt) causes a selective hydrolysis reaction producing new monoimine complexes. The resulting complexes are characterized by a combination of infrared spectroscopy, elemental analysis, mass spectrometry and, in the cases of the zinc complexes, 1 H NMR spectroscopy. The structures of all six complexes are confirmed by single-crystal X-ray crystallographic studies.