Studies involving nitrogen–oxygen donor macrocyclic ligands. Interaction of copper(II) with new O2N3-donor macrocycles and the X-ray analysis of aqua(1,12,16-triaza-3,4:9,10-dibenzo-5,8-dioxacyclo-octadecane)copper(II) diperchlorate hydrate

摘要: The interaction of Cu2+ with three new O2N3-donor macrocycles has been investigated. Complexes the type CuL(ClO4)2.nH2O and CuLX(ClO4).nH2O (where L = macrocycle, X Cl or Br, n= 0, 1, 2) have isolated. Conductance studies indicate that halide ions in latter complexes are co-ordinated dimethyl sulphoxide. All show expected magnetic moments for S=½. Potentiometric titration 95% methanol (I= 0.1 mol dm–3, [NMe4]Cl) following equilibria involving occur : Cu2++ ⇌ CuL2+ HL+⇌ Cu(HL)3+ respective formation constants determined. X-ray structure [CuL3(OH2)][ClO4]2·H2O indicates this complex a pseudo-square-planar co-ordination geometry sphere consisting nitrogen atoms macrocycle [Cu–N, 1.97(3)–2.07(2)A] together an oxygen from water [Cu–O, 1.96(2)A]. ether donors do not co-ordinate. Crystals monoclinic, space group P21/c, a= 16.856(7), b= 10.717(4), c= 16.738(18)A, β= 110.59(5)°, Z= 4, R being 0.12 1 044 ‘observed’ reflections.