Binuclear copper(II) complexes containing phenols and catechols

Article abstract of DOI:10.1016/0020-1693(95)04726-3

The synthesis and characterisation of a series of binuclear copper(II) complexes of ligands formed by the condensation of substituted salicylaldehydes and 1,3-diamino-2-propanol (SalDplH3) and 1,5-diamino-3-pentanol (SalDpeH3) and their interaction with both phenols and catechols are reported. Spectroscopic and magnetic data suggest that the neutral phenols and catechols can bind to binuclear copper(II) complexes without actually coordinating to the copper atoms. The crystal and molecular structure of two binuclear copper(II) complexes have been solved. The μ-hydroxobridged dicopper(II) complex of SalDpe(3-), [Cu2SalDpe(OH)], C19H20O4N2 Cu2, I, having the space group P1- and cell dimensions, a=8.475(3), b=15.727, c=6.999(2) ?, α=99.51(2), β=92.84(3), γ=77.66(2)° was solved for 1839 structure factors (I > 3.0σ(I)) and Z=2, R=4.2, R(w)=4.3%. The 4-ethylphenol adduct of the μ-(O,O')phenylacetate bridged dicopper(II) complex SalDplH3, [Cu2SalDpl(Phenac)(4-Ethylphenol)], C33H31N2O6Cu2, II, having the space group P1- and cell dimensions, a=11.872(2), b=13.418(3), c=11.046(2) ?, α=101.95(2), β=103.65(1), γ=113.35° was solved for 3833 structure factors (I > 3.0σ(I)) and Z=2, R=4.1, R(w)=4.3%. The 4-ethylphenol group is involved in a strong hydrogen bond to one of the phenolic oxygen donor atoms of the SalDpl(3-) ligand and weaker hydrogen bond to the adjoining oxygen donor atom of the bridging phenylacetate ion. The other phenolic oxygen donor atom is involved in an out-of-plane interaction toone of the copper atoms.