Copper(II) chelates with isomeric schiff-base ligands. derivatives of 1- and 2-adamantanamines

The syntheses of isomeric copper(II) Schiff base complexes formed by the condensation of 1- and 2-adamantanamines with salicylaldehyde, o-vanillin and pyrrole-2-carboxaldehyde are described. The electronic structures of the complexes have been probed using electronic absorption and electron paramagnetic resonance (EPR ) spectroscopy. The electronic sectra indicate that both the 1-and 2-adamantyl groups lead to distortions from planar geometry with the 1-adamantyl substituted compounds being the most “tetrahedral”. The pseudotetrahednd geometries of the 1-adamantyl substituted derivatives are further supported by the comparatively lower isotropic electron spin-nuclear spin hyperfine coupling constants observed in the EPR spectra.