C-H Bond Activation in Matrices

Many of the above complexes have been examined by photolysis in inert and reactive gas matrices. These experiments, in general, provide evidence for the photochemical generation of the 16-electron coordinatively unsaturated intermediates, their weak interaction with inert gas atoms or methane, and in several cases their eventual reaction with methane by C-H activation. The applicability of this method to a particular system depends upon the volatility of the metal complex precursor, as the species must go into the gas phase during deposition in the matrix. Several examples are given below. 

Rest and Graham reported in 1984 that the metal carbonyl complexes CpRh(CO)2, CpIr(CO)2, and Cp Ir(CO)2 can be deposited in methane matrices at 12 K and irradiated to give the corresponding methane oxidative addition products [28]. In addition, the dihydride CpIr(CO)H2 could be irradiated in a methane/argon matrix to generate CpIr(CO)(CH3)H by an alternative route [29]. While the dicarbonyl compounds were not efficient producers of the coordinatively unsaturated intermediate, Perutz found that CpRh(CO)(C2H4) lost 

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