Thermodynamic study of dinuclear adducts between copper(II) Salen-type complexes and organotin(IV) chlorides in acetonitrile

Abstract

Adduct formation between R 2 SnCl 2 (R ¼ methyl and phenyl) and PhSnCl 3 as acceptors and Cu(II) complexes of tetradentate Schiff-base ligands [CuL][Salophen, bis(salicylaldehyde)phenylenediimine], [3-MeOSalophen, N,N 0 -bis(3-methoxysalicylaldehyde)phenylenediimine], and [5-MeOSalophen, N,N 0 -bis(5-methoxysalicylaldehyde)phenylenediimine], as donors have been investigated in acetonitrile by UV-Vis spectrophotometric analysis. The formation constants and thermodynamic free energies were measured using UV-Vis titration for 1 : 1 adduct formation at various temperatures (T ¼ 293-313 K). The trend of adduct formation for copper Schiff-base complexes with a given tin acceptor decreases as follows: Cuð5-MeOSalenÞ

Synthesis, characterization, and formation constant of hexacoordinate iron(III) complexes

“…Conversely, electron-withdrawing groups such as NO 2 bind more weakly. This behavior confirms the results obtained in the recent work [38,39] related to adducts between different substituted Schiff-base complexes of Ni(II) and Cu(II) with organotin(IV) dichloride. Also, our previous work on thermodynamics of different types of Co(III) Schiff-base complexes as acceptor with donors such as phosphites [20,24,40] and amines [21,26] agrees with our present work on Fe(III) Schiff-base complexes.…”