CH Activation is a Selective, Coordination Reaction

Many chemical approaches, summarized in Fig. 7.9, are being considered to develop technologies to convert methane. However, the approaches that have shown the greatest potential for developing low temperature, selective processes for the hydroxylation of the CH bond are based on the CH Activation reaction using homogeneous catalysts. 

There are many definitions of the CH activation reaction. As shown in Fig. 7.8, we define CH activation as a facile CH cleavage reaction with an MX species that proceeds by coordination of an alkane to the inner-sphere of M (either via an intermediate alkane complex or a transition state) leading to a M-C intermediate [4]. Emphasized in this definition is the requirement that during the CH cleavage, the hydrocarbyl species remains in the inner-sphere and under the influence of M [5]. 

The key characteristic of iimer-sphere reactions that can lead to high rates and selectivities is the strong covalent forces between the CH bond and M . The CH bond of methane is strong (homolytic bond strength of -105 kcal/mol) and an important feature of the CH activation reaction is the formation of strong M-C bonds that compensate for breaking the CH bond. This is one of 

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