Synthesis, kinetics, and mechanism for adduct formation of tetraaza Schiff base cobalt(II) complexes with diorganotin(IV)dichlorides in dimethylformamide solvent

✍ Scribed by Mozaffar Asadi; Zahra Asadi; Fatemeh Mosalanezhad

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 209 KB
• Volume: 42
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.20499

✦ Synopsis

Abstract

The kinetics and mechanism of the adduct formation of diorganotin(IV)dichlorides with Co(II) tetraaza Schiff base complexes, such as [Co(ampen)] {[N,N′‐ethylenebis‐(o‐amino‐α‐phenylbenzylideneiminato)cobalt(II)]}, [Co(campen)] {[N,N′‐ethylenebis‐(5‐chloro‐o‐amino‐α‐phenylbenzylideneiminato)cobalt(II)]}, and [Co(amaen)] {[N,N′‐ethylenebis‐(o‐amino‐α‐methylbenzylideneiminato)cobalt(II)]}, were studied spectrophotometrically. The kinetic parameters and the rate constant values show the following acceptor tendency trend for the diorganotin(IV)dichlorides: Ph~2~SnCl~2~> Me~2~SnCl~2~> Bu~2~SnCl~2~. Adducts have been separately synthesized and fully characterized by ^119^SnNMR, IR, UV–vis spectra, and elemental microanalysis (C,H,N) methods. The trend of the rate constants for the adduct formation of the cobalt complexes with a given tin acceptor decreases as follow: Co(amaen) > Co(ampen) > Co(campen). The linear plots of k~obs~ vs. the molar concentration of the diorganotin(IV)dichlorides, the high span of the second‐order rate constant k~2~ values, and the large negative values of AS^≠^ suggest an associative (A) mechanism for the acceptor–donor adduct formation. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 499–507, 2010