Kinetic studies of the impact of thiocyanate moiety on the catalytic properties of Cu(II) and Fe(III) complexes of a new Mannich base

摘要

Four new metal complexes of a novel Mannich base 5-methyl-2-((4-(pyridin-2-yl)piperazin-1-yl)methyl) phenol (HL) have been prepared. The compounds were characterized by an array of analytical and spectroscopic methods including Nuclear Magnetic Resonance, Infra-red and UV Visible spectroscopy. Compounds 1-4 behaved as effective catalysts towards the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) to its corresponding quinone in the presence of molecular oxygen in DMF solution while compound 4 proved to be the best catalyst with a turnover rate of 17.93 +/- 1.10 h(-1) as other complexes showed lower rates of oxidation. Also with the exception of dinuclear iron complex (4); thiocyanate containing Cu(II) complex exhibited lower catecholase activity compared to the Cu(II) complex without it. (C) 2017 Published by Elsevier B.V.