Synthesis and characterization of 5,12-dimethyl-7,14-diphenyl-1,4,8,11- tetraazacyclotetradecane-4,11-diacetic acid and its transition metal complexes; crystal structure of the copper(II) complex of the macrocycle
The synthesis and characterization of a new 14-membered tetraazamacrocyclic ligand 5,12-dimethyl-7,14-diphenyl-1,4,8,11-tetraazacyclotetradecane-4,11-diacetic acid (H2L1) is reported. Cobalt(III), nickel(II), and copper(II) complexes with this ligand were prepared and characterized by infrared, electronic, and electron spin resonance (esr) spectra and in one case by X-ray crystallography. The complex CuL1•2CH3CH2OH (3) crystallized in the triclinic system, space group[Formula: see text], with a = 8.440(2), b = 13.445(2), c = 7.523(1) Å, α = 99.30(1), β = 106.57(1), γ = 87.00(1)° and Z = 2 (R = 0.027, Rw = 0.028 for 2618 reflections). The complex shows a distorted trans-octahedral geometry with four amino nitrogens in a plane and two apical carboxylate oxygen donors.