Copper(II) complexes with novel chiral amidate ligands

Two new copper(II) complexes, {[Cu2(S-alaamp)2(ClO4)]ClO4}n (1) and [Cu(S-valamp)(H2O)(ClO4)] (2) [where S-alaamp=4(S)-1-(2-pyridyl)-3-oxo-4-amino-2-azapentane, S-valamp=4(S)-1-(2-pyridyl)-3-oxo-4-amino-4,5-dimethyl-2-azahexane] are prepared and characterized. Compound 1 exists as 1-D polymeric chain where an amide oxygen atom is linked to adjacent copper(II) ion, while 2 is a square-pyramid in the solid state. Compounds 1 and 2 are involved in offset π–π stacking interactions via the pyridine groups of the ligands, which give rise to 2-D sheets.