2012 年 11 巻 3 号 p. 125-130
The calculations of a C–H bond activation were carried out with a two-layer ONIOM (MO:MM) method using DREIDING for the low layer and density functional theory (DFT) at the B3LYP level for the high layer. One of the calculated elementary reactions was that from (C5Me5)Ru(μ-CH2=CH2)(μ-H)2Ru(C5Me5) (4) to (C5Me5)Ru(μ-CH=CH2)(H)(μ-H)2Ru(C5Me5) (5) (eq 2) and the other was that from (C5Me5)Ru(C2H5)(μ-CH2=CH2)(μ-H)Ru (C5Me5) (6) to (C5Me5)Ru(C2H5)(μ-CH=CH2)(H)(μ-H)Ru(C5Me5) (7) (eq 3). All the optimized geometries were consistent with the intermediates in keeping with the phenomenon of "bimetallic activation" reaction where the two metal centers work concertedly in a reaction. The activation free energies of eqs 2 and 3 were 18.8 and 6.9 kcal/mol, respectively. The calculations of two types of C–H bond activation pathways that respectively contain eqs 2 and 3 were carried out. These results suggested that the pathway containing eq 3 was suitable.
