Donor property of cobalt(II) Schiff base complexes toward triphenyltin(IV)-chloride: A kinetic study

Abstract

In this study, some cobalt(II)tetraaza Schiff base complexes were used as donors in coordinating to triphenyltin(IV)chloride as acceptors; the kinetics and mechanism of the adduct formation were studied spectrophotometrically. Co(II)tetraaza Schiff base complexes used were [Co(amaen)][N,N′-ethylene-bis-(o-amino-α-methylbenzylideneiminato)cobalt(II)] (1), [Co(appn)] [N,N′-1,2-propylene-bis-(o-amino-α-phenylbenzylideneiminato)cobalt(II)] (2), [Co(ampen)] [N,N′-ethylene-bis-(o-amino-α-phenylbenzylideneiminato)cobalt-(II)] (3), [Co(cappn)][N,N′-1,2-proylene-bis-(5-chloro-o-amino-α-phenylbenzylideneiminato)cobalt(II)] (4), and [Co(campen)] [N,N′-ethylene-bis-(5-chloro-o-amino-α-phenylbenzylid-eneiminato)cobalt(II)] (5). The reactivity trend of the complexes in interaction with triphenyltin(IV)chloride was Co(amaen) > Co(appn) > Co(ampen) > Co(cappn) > Co(campen). The linear plots of kobs versus the molar concentration of the triphenyltin(IV)chloride, a high span of the second-order rate constant k2 values, and large negative values of ΔS≠ and low ΔH≠ values suggest an associative (A) mechanism for the acceptor–donor adduct formation. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 635–640, 2012