Hydride dynamic behavior

Perutz and coworkers [180] have used 2D EXSY to study the dynamic behavior of RhCp(PMe3)(q -naphthalene), 109, which is thought to be a model intermediate for the oxidative addition of arenes to a metal center. In this complex, there are two processes taking place. The first involves an equilibrium between the -naphthalene complex, 109, and the naphthyl hydride complex, 110. The second process involves an intramolecular [l,3]-shift which moves the coordination site of the naphthalene ring from one side of the ring to the other (Scheme 1.12). 

The Extraordinary Dynamic Behavior and Reactivity of Dihydrogen and Hydride in the Coordination Sphere ofTransition Metals... 

Transition metal hydrides and dihydrogen are important molecules which are involved in most homogeneous catalytic reactions. Due to their relative simplicity and their accessibility using H NMR spectroscopy, these molecules have been the basis of numerous relevant experimental observations, which have significantly increased our understanding of reaction mechanisms in solution. Examples of this are the activation of a-bonds and the dynamic behavior of unsaturated complexes in solution. 

Taking into account the usual dynamic behavior in solution of mononuclear polyhydrides, the occurrence of these intermetallic hydride exchanges is not surprising, although its importance can not be underestimated. In fact, hydride transfer among metals has been found to be crucial in order to observe intermetallic cooperation in polynuclear catalysts. This subject will be analyzed in the... 

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