Synthesis, Crystal Structure, and Spectroscopic Properties of Cu(II) Complex with 14-Membered Hexaazamacrocyclic Ligands

[CuL(ClO4)2] complex of 14-membered hexaazamacrocyclic ligand (L = 6,13-dimethyl-3,10-dioctyl-1,3,5,8,10,12-hexaazacyclotetradecane) was synthesized by template condensation reaction of 1,2-diaminopropane, octylamine, and formaldehyde in ethanol. The product was characterized by elemental analysis, Fourier-transformed infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV–vis), diffused reflectance spectroscopy (DRS), liquid chromatography-mass spectrometry (LC–MS), and X-ray crystallographic technique. Thermal behavior of this complex was studied by thermogravimetric analysis (TGA). The IR and other spectral properties were consistent with the result from X-ray diffraction. The electronic absorption spectra of [CuL(ClO4)2] complex showed one band at 500 nm corresponding to 2B1g → 2B2g transition. The complex crystallized in the triclinic space group of Pī with a = 8.1307(6) A, b = 9.3579(7) A, c = 13.3930(10) A, α = 95.932(2)°, β = 98.579(2)°, and γ = 114.478(2)°. The copper(II) ion of the macrocyclic cation displayed a tetragonally distorted octahedral geometry with four nitrogen atoms in the equatorial plane and two oxygen atoms from the perchlorate ions weakly coordinated to the copper(II) ion in the axial positions. The complex exhibited only weak luminescent property. A new macrocyclic complex that can be easily obtained from the one-pot synthesis.