Nature of M-E Bonds in Metallosilylenes, -germylenes, -stannylenes, and -plumbylenes [(eta(5)-C5H5)(Me3P)(H)(2)M(EPh)] (M = Fe, Ru, Os; E = Si, Ge, Sn, Pb)

作者：Pandey Krishna K^*; Power Philip P

来源：Organometallics, 2011, 30(12): 3353-3361.

DOI：10.1021/om200252t

Geometry, electronic structure, and bond energy analysis of M ER bonds in the terminal metallosilylenes, metallogermylenes, metallostannylenes, and metalloplumbylenes of iron, ruthenium, and osmium [(eta(5)-C5H5)(Me3P)-(H)(2)M(EPh)] (I, M = Fe, E = Si; II, M = Fe, E = Ge; III, M = Fe, E = Sn; VI, M = Fe, E = Pb; V, M = Ru, E = Si; VI, M = Ru, E = Ge; VII, M = Ru, E = Sn; VIII, M = Ru, E = Pb; IX, M = Os, E = Si; X, M = Os, E = Ge; XI, M = Os, E = Sn; XII, M = Os, E=Pb) were investigated at the DFT/BP86/TZ2P/ZORA level of theory. The M E bonds in these complexes are essentially M E single bonds. In all studied complexes, the pi-bonding contribution to the total M EPh bond is significantly smaller than that of the a-bonding and increases upon going from M = Fe to Os. Thus, in the EPh ligands the E atom is predominantly a sigma-donor. The nature of E has a significant effect on the M P bonding to the Me3P ligand trans to EPh. The M P bond distances decrease upon going from SiPh to PbPh. The contributions of the electrostatic interactions Delta E-elstat to the M EPh bonds are larger in all complexes than the covalent bonding Delta E-orb. The M E bond in each case has a degree of covalent character of between 36% and 48%. In contrast to the interaction between charged fragments, where the electrostatic interactions Delta E-elstat are greater that the orbital interactions Delta E-orb, the orbital interactions Delta E-orb are larger than the electrostatic interactions Delta E-elstat for interaction between neutral fragments. In the case of homolytic bond dissociation, the M E bond in each case has a degree of covalent character of between 56% and 64%.

• 出版日期2011-6-27