Basic Mechanisms of Pt II Complex Formation

Cisplatin is normally administered by the intravenous route and less frequently delivered via the intraperitoneal route. 

It is the purpose of the present efforts to incorporate the platinum atom in various polymers to produce cw-platin-related drugs with enhanced anticancer activity and overall lowered toxicity. 

Transition metal square-planar complexes generally contain eight d electrons and are almost always diamagnetic. This includes complexes of Pt, Pd % Au, Rh, and Ir. While such complexes can imdergo other reactions such as redox processes, we shall focus on substitution reactions. Good reviews of square-planar substitution reactions are available. The following is a summary of some of these substitution processes, wifli emphasis on those involved with polymer formation. These substitution reactions are the most widely studied of the transition metal square-planar complex reactions. 

As with many reactions, the final structure depends on the starting material and the order of addition, as illustrated with the following simple reactions.  

The overriding factor determining the structure of Pt(ll) complexes is the effect that the ligand trans to the substitution site has on the rate of substitution. This effect is called the trans effect and was recognized in the early 1900s. The general trans effect order is  

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