Tuning Reactivity of Platinum(II) Complexes

Figure 5.2 Variation of absorbance with pH for qzn complex in the pH range
2-10, I = 0.1 M HClO4, T = 25 °C. Inset: Plot of Absorbance versus
pH at 305 .0 nm………...................................................................................13
Figure 5.3 1H NMR spectra of the reaction of cis-[{PtCl(NH3)2}2-μ-pzn] +2 and
excess thiourea (TU)……………………………………………………………....18
Figure 5.4 1H NMR spectra of the reaction of cis-[{Pt(OH2)(NH3)2}2-μ-pdn] +4
and 20-fold excess thiourea (TU) ……………………………………………19
Figure 5.5 (a) Stopped-flow and (b) UV-Vis Spectrophotometric kinetic
traces for the reaction between qzn and TU recorded at 305 nm, T
= 25 °C, pH = 2.0. The inserts in (b) represent the substitution of
the second ………….........................................................................................21
Figure 5.6 Concentration dependence of kobs(1 st ) for the displacement of first
aqua ligand in pmn by thiourea and its substituted derivatives, pH
= 2.0, T = 298.15 K ………………………………………………………….………24
Figure 5.7 Concentration dependence of kobs(2 nd ) for the displacement of
second aqua ligand in pmn by thiourea and its substituted
derivatives, pH = 2.0, T = 298.15 K………………………………….…….....24
Figure 5.8 Concentration dependence of kobs(3 rd ) for the displacement of the
bridging ligand in pmn by thiourea and its substituted
derivatives, pH = 2.0, T = 298.15 K……………………………………..…...25
Figure 5.9 Plots of ln(k2/T) versus 1/T for the first reaction step of pmn with
a series nucleophiles in the temperature range 15-35
°C……………………………………......................................................................28
Figure 5.10 Plots of ln(k2/T) versus 1/T for the second reaction step of pmn
with a series nucleophiles in the temperature range 15-35
°C………………………………………………………………………………………….28
Figure 5.11 Plots of ln(k2/T) versus 1/T for the third reaction step of pmn
with a series nucleophiles in the temperature range 15-35
°C………………………………………………………………………………….….…...29
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