Template-directed synthesis of macrocyclic copper(II) complexes of diazacyclam, 1,3,6,10,12,15-hexaazatricyclo[13.3.1.1 ]eicosane.

Hakimi, Mohammad; Moeini, Keyvan; Mardani, Zahra; Fernandes, ManuelA.; Mohr, Fabian; Schuh, Esther

Template reaction of copper(II) nitrate with N-(2-aminoethyl)-1,3-diaminopropane and formaldehyde yields a macrocyclic copper(II) complex of 1,3,6,10,12,15-hexaazatricyclo[13.3.1.16,10]eicosane (L), [CuL(NO3)2] (1). Replacement of nitrate with perchlorate gives [CuL(ClO4)2] (2). These complexes have been characterized by FT-IR and Raman spectroscopies, electronic absorption, cyclic voltammetry, and X-ray crystallography. The crystal structure of 1 shows that copper has distorted octahedral geometry with two secondary and two tertiary amines of the macrocycle and two oxygen atoms from nitrate coordinating the axial positions. The copper in 2 has the same geometry with axial positions occupied by one oxygen atom of perchlorate. Copper lies on the plane of four coordinated nitrogen atoms and there is no rms deviation from this plane. Cyclic voltammetry of 1 and 2 gives two one-electron waves corresponding to CuII/CuIII (−0.75, −0.72) and CuII/CuI (0.48, 0.24) processes. For understanding of geometry parameters in diazacyclam-based copper(II) complexes, a survey on complexes from CSD structures is presented. In this study the macrocycle hole size was estimated by ionic radii of metal ions located inside of it.

TRANSITION metal complexes; COMPLEX compounds synthesis; CHEMICAL templates; ORGANOCOPPER compounds; MACROCYCLIC compounds; NITRATES; CHEMICAL reactions; CRYSTAL structure

Journal of Coordination Chemistry, 2012, Vol 65, Issue 7, p1232

0095-8972

Academic Journal

10.1080/00958972.2012.669834