Abstract
Adduct formation between R2SnCl2 (R = methyl and phenyl) and PhSnCl3 as acceptors and Cu(II) complexes of tetradentate Schiff-base ligands [CuL], where L = [Salen, bis(salicylaldehyde)ethylenediimine], [3-MeOSalen, N,N′-bis(3-methoxysalicylaldehyde)ethylenediimine], [5-MeOSalen, N,N′-bis(5-methoxysalicylaldehyde)ethylenediimine], [5-BrSalen, N,N′-bis(5-bromosalicylaldehyde)ethylenediimine], [salpn, N,N′-bis(salicylaldehyde)1,3-propanediimine], [Salophen, bis(salicylaldehyde)phenylenediimine], [3-MeOSalophen, N,N′-bis(3-methoxysalicylaldehyde)phenylenediimine], and [5-MeOSalophen, N,N′-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 = 293–313 K). The trend of adduct formation for copper Schiff-base complexes with a given tin acceptor decreases as follows:
;
The trend of the reaction of R
n
SnCl4−
n
acceptors toward a given copper Schiff-base complex is PhSnCl3 > Ph2SnCl2 > Me2SnCl2. The reactivity of PhSnCl3 toward Cu(Salen), Cu(Salpn), and Cu(Salophen) increases with increasing temperature.
Acknowledgements
We are grateful to Kurdistan University Research Council for their financial support. Thanks are also given to Prof. Mozaffar Asadi, Dr Khosrow Aein Jamshid, Dr Sajjad Mohbbi, and Islam Abroshan.