Design and reactivity of pentapyridyl metal complexes for ammonia oxidation.

Oxidation of NH3 to N-2 by pentapyridyl metal complexes via hydrogen atom abstraction was investigated computationally. Quantum chemical analysis reveals insights on orbital symmetry requirements for efficient NH3 oxidation. The most promising complex, [(PY5)Mo(NH3)](2+), was studied experimentally. It shows conversion of NH3 to N-2 upon treatment with 2,4,6-tri-tert-butylphenoxyl radical.