An unusual Cu(II) complex of a Schiff-base ligand of 3-aminoquinoline with a hydronated pyridine unit: Synthesis, characterizations, and computational studies

Author(s):
Nayak, S.; Pevec, A.; Seaton, C.C.; Gamez, P.; Reedijk, J. (0000-0002-6739-8514)
Published
2016
Publication type
Article / Letter to editor

Abstract

A very unusual Cu(II) compound of formula [Cu(mqmp)(2)(ClO4)(2)] was synthesized in situ from a one-pot reaction between copper(II) perchlorate and a Schiff base ligand, 2-methoxy-6-((quinolin-3-ylimino) methyl)phenol, abbreviated mqmp. The resulting compound, bearing positively charged side groups was characterized using single-crystal X-ray diffraction, elemental analysis, electrospray-ionization mass spectrometry (ESI-MS), infrared spectroscopy (IR), ligand-field (LF) spectroscopy, and powder electron paramagnetic resonance (EPR) spectroscopy. The coordination chromophore consists of tetragonal [CuN2O2O2'] units. The compound shows a step-like molecular assembly assisted by hydrogen-bond interactions from -NH+ to ClO4- between the neighbouring molecules. The presence of pyridinic nitrogens bearing a H+ ("hydron") on the quinoline unit is quite unusual, and was validated with computational studies which clearly suggested that this hydronated nitrogen stabilizes the structure by 164 kJ mol(-1) compared to the hydronated phenolic version of the structure. (C) 2016 Elsevier Ltd. All rights reserved.

Date issued
2016-03-09
Language
English
Publisher
PERGAMON-ELSEVIER SCIENCE LTD
Is part of
hdl
1887/3201136
doi
10.1016/j.poly.2016.01.009