Tuning Reactivity of Platinum(II) Complexes

against the concentration of the incoming nucleophiles to determine the second-order
rate constant, k2, which were obtained from the slopes of the plots and k-2 that were
obtained from the y-intercept in some of the complexes. The kobs values used were an
average of five to eight runs. All the kinetic data obtained gave straight-line fits with
significant non-zero intercepts in some cases for each of nucleophiles as shown in
Figures 3.3(a & b) (also Figures SI 3.2(a & b) and Tables SI 3.2(a & b) and 3.3 (a & b)
appendix). The mechanistic pathway is irreversible and independent of the solvent
when k-2 is zero. Therefore, the mechanism of the substitution can be represented by
Equation 1 and the corresponding rate law is given by Equation 2.
kobs = k2 [NU] + k-2 (2)
The representative plots shown in Figures 3.3(a & b) clearly illustrate that the
substitution reactions are first-order with respect to the incoming nucleophile. The
values of k2 obtained are summarised in Table 3.2. Also included in Table 3.2 are
literature values for PtCl for comparison.
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