Calculating the excited state reactivity of a manganese(IV)-oxo species with a negatively charged ligand

It was previously found that (MnO)-O-IV species with neutral ligands perform C-H activation reactions through an excited state reactivity (ESR), where a valence electron in the (MnO)-O-IV moiety is spontaneously excited to a higher orbital to create a more potent reactant. We extend this to a (MnO)-O-IV compound with a negatively charged ligand ([Mn-IV(O)(DPAQ)](+)), which we investigate with density functional theory. It is found that ESR are indeed preferable even in this case, and that the ligand charge may only have an indirect effect on ESR. Instead, ligand rigidity is proposed to affect the ESR rate more directly. In addition, an example of a new beta-electron transfer pathway was found, where three key orbitals mix to deliver the incoming electron to its final orbital position. This study supports the notion that ESR may be more common in C-H activation reactions of (MnO)-O-IV compounds than what is so far known.

Automated summary

It has been discovered that (MnO)-O-IV species with neutral ligands undergo C-H activation reactions through excited state reactivity (ESR), where a valence electron in the (MnO)-O-IV moiety is excited to a higher orbital to create a stronger reactant. The study extends this finding to a (MnO)-O-IV compound with a negatively charged ligand ([Mn-IV(O)(DPAQ)](+)) and investigates it using density functional theory. The results show that ESR is still preferred in this case, and the ligand charge may only have an indirect impact on ESR, while ligand rigidity is proposed to directly affect the ESR rate. Furthermore, a new beta-electron transfer pathway is discovered, where three key orbitals mix to deliver the incoming electron to its final orbital position. This study supports the idea that ESR may be more common in C-H activation reactions of (MnO)-O-IV compounds than previously known.