The Role of an Alkyl–Phenyl Spacer on the Reactivity of Novel Platinum(II) Complexes with Thiourea Nucleophiles

The presented work, submitted as a paper, deals with the substitution reactions of mononuclear and dinuclear platinum(II) complexes of di‐2‐pyridylaminodiaquaplatinum(II), ( Pt1 ); di‐2‐pyridylaminomethylbenzenediaquaplatinum(II), ( Pt2 ); 1,2‐bis(di‐2‐pyridylaminomethyl)benzenetetraquaplatinum(II), ( Pt3 ); 1,3‐bis(di‐2‐pyridylamino‐methyl)benzenetetraquaplatinum(II), ( Pt4 ); and 1,4‐bis(di‐2‐pyridylaminomethyl)‐benzenetetraquaplatinum(II), ( Pt5 ). These reactions were carried out on aqua complexes by three nucleophiles, viz., thiourea, N ,N ′‐dimethylthiourea, and N ,N ,N ′N ′‐tetramethylthiourea under pseudo–first‐order conditions as a function of nucleophile concentration and temperature by stopped‐flow and UV–visible spectrophotometric techniques. In addition, some DFT calculation was performed. The activation parameters support an associative substitution mechanism.