Bond dissociation energy metal-methyl

The addition of several ligands to the metal system can reverse relative metal methyl and metal hydrogen bond dissociation energies. For example, reaction 5 is observed to be a last exothermic process,... 

The increase in bond strength going from id to 4d to 5d correlates with an increase in the bonding overlaps between the 2cr CH3 orbital and the (p, d) hybrid cr MLn orbital on the metal center (in [M(CH3)(CO)5]), as shown in Fig. 4. The M-C(methyl) bond dissociation energies in [M(CH3)(C0)5] (M = Mn, Re) have been measured and were found to be 117 kJ/mol for M = Mn and 223 kJ/mol for M = Re, indicating a much stronger Re-C(alkyl) bond (49). More recent calculations have been reported by McQuillan et al. (65) these results were discussed in Section III. 

Table 11.2. Cationic Metal-Hydride and Metal-Methyl Bond Dissociation Energies (heal mol ) Calculated by a Generalized Valence Bond Method (References 34 and 35) ...

Table 13 Calculated and Experimental Metal—Carbon Bond Dissociation Energies Dg (kcal/mol) of Group 11 and 12 Methyl and Phenyl Compounds Using Hay—Wadt Pseudojxrtentials Geometries Optimized at MP2/II (see Table 12)... 

In this chapter we have been concerned with the dissociation energies of M—R bonds in compounds of the type MR,. In the group of compounds investigated, M is either a transition metal, a representative metal (e.g. Li, Al) or a 6-Group metal (e,g. Zn, Ga). The group R is either an organic radical (e.g. methyl, cj clo-pentadienyl) or a halogen atom. 

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