What can metal-ligand bonding energetics teach us about stoichiometric and catalytic organometallic chemistry?

This contribution surveys recent progress in the thermochemistry of lanthanide, actinide, and early transition element organometallic compounds. General trends in metal-ligand bond enthalpy patterns across the transition series can be understood largely on the basis of straightforward electronegativity concepts. Metal-ligand bonding energetics in such unusual species as metallacycles, early transition element carbonyls and benzynes, as well as in actinide carbonyls are also quantified. Such data furthermore provide a deeper insight into d⁰, f⁰- centered β-hydride/β-alkyl elimination, cyclometalation, and hydrocarbon functionalization processes, as well as into U(IV)-centered elimination reactions. New reactions which are examined in the light of metal-ligand bond enthalpy data include binuclear organolanthanide-centered hydrocarbon activation and organo- lanthanide-catalyzed hydroamination of olefins.