Bipyrimidyl platinum

The activation of C-H bonds is one of the elementary steps in chemistry. Intensive research has lead to homogeneous as well as heterogeneous systems which can activate the strong C-H bonds (cf. Section 3.3.6). There are numerous experimental studies which have more recently often been accompanied by theoretical calculations. The two best known examples for the activation of methane are the so-called Shilov system K2PtCl4 [1], which was one of the first systems reported, and the [Pt(bpym)Cl2] system of Periana, which is currently the most active system reported for the direct, low-temperature, oxidative conversion of methane to methanol by platinum salts such as dichloro( /-2-[2,2 -bipyrimidyl])platinum(II) [Pt(bpym)Cl2] with yields of more than 70% and a selectivity of 80% [2]. 

Later, Periana and coworkers proposed (2,2 -bipyrimidyl)platinum(ll)dichloride as a catalyst ( Periana system see a recent review [4d]). Fuming sulfuric acid is the oxidant in this case. A simplified scheme of the catalytic cycle is shown in Fig. 1.2. It can be seen that some intermediates contain a-methyl-platinum bonds. 

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