Selective Nitrogen-Atom Transfer Driven by a Highly Efficient Intersystem Crossing in the [CeON]+ /CH4 System.

The thermal gas-phase reactions of [CeON]+ with methane have been explored by FT-ICR mass spectrometry and high-level quantum-chemical calculations. Nitrogen-atom transfer from the cluster ion to methane was observed as the only reaction channel. Based on computational work, the neutral molecule formed corresponds to either CH2 NH2 or CH3 NH. In addition to a rather weak OCe+ -N bond, this reaction benefits from a highly efficient intersystem crossing. Mechanistic aspects and the associated electronic origins are discussed, and a detailed comparison of [CeON]+ , [CeO]+ , [CeN]+ , [CeO2 ]+ , and atomic N in their reactions with CH4 is given.