Copper(II) Bipyridine and Crown Ether-Bipyridine Complexes: X-ray Structures, Characterization, and Properties as Histamine Receptors

Abstract

Abstract he synthesis and characterization, including the crystal structure, of the complex (2) of Cu(II) with the crown-ether bipyridine ligand, 1[5–2,2′-bipyridyl)carbonyl]-1-aza-4,7,10,13-tetraoxacyclopentadecane (1), are described. Compound 2, C27H49N3O18Cl2Cu, crystallizes in the triclinic space group P1 with cell constants a = 10.160(1), b = 13.014(1), c = 15.934(2) A, α = 74.18(1)°, β = 84.83(1)°, γ = 71.54(1)°, V = 1923.0(4) A3, Z = 2, dcalc = 1.448 g cm−3. The crystal structure was solved by vector search methods and refined by full-matrix least-squares on F2 to R = 0.086 for 3163 observed reflections (I > 2σ(I)), 83 restraints and 390 parameters. The crystals contain two formula units per cell as a dimer, with each carbonyl oxygen of one monomer complex coordinating to the copper ion of the other. Each copper has elongated octahedral coordination geometry, with two nitrogens of one bipyridyl unit and four oxygens, viz. two water molecules, one perchlorate, and one carbonyl, as ligand donor atoms...