Abstract
Neptunium is an actinide element sourced from anthropogenic production, and, unlike naturally abundant uranium, its coordination chemistry is not well developed in all accessible oxidation states. High-valent neptunium generally requires stabilization from at least one metal–ligand multiple bond, and departing from this structural motif poses a considerable challenge. Here we report a tetrahedral molecular neptunium(V) complex ([Np5+(NPC)4][B(ArF5)4], 1-Np) (NPC = [NPtBu(pyrr)2]−; tBu = C(CH3)3; pyrr = pyrrolidinyl (N(C2H4)2); B(ArF5)4 = tetrakis(2,3,4,5,6-pentafluourophenyl)borate). Single-crystal X-ray diffraction, solution-state spectroscopy and density functional theory studies of 1-Np and the product of its proton-coupled electron transfer (PCET) reaction, 2-Np, demonstrate the unique bonding that stabilizes this reactive ion and establishes the thermochemical and kinetic parameters of PCET in a condensed-phase transuranic complex. The isolation of this four-coordinate, neptunium(V) complex reveals a fundamental reaction pathway in transuranic chemistry. (Figure presented.)
| Original language | English |
|---|---|
| Pages (from-to) | 1490-1495 |
| Number of pages | 6 |
| Journal | Nature Chemistry |
| Volume | 16 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 2024 |
| Externally published | Yes |
Funding
We thank C. Windorff (NMSU) for his support during laboratory set-up and the initial transuranic synthesis. This material is based on work supported by the United States Department of Energy, Office of Science, Office of Basic Energy Sciences, Heavy Element Chemistry programme under award no. DE-SC0019385 (J.E.N., K.S.O. and H.S.L.P.) at the Georgia Institute of Technology. Computational work was conducted using the computational resources at the Ohio Supercomputer Center and the ARCC HPC cluster at the University of Akron (C.M.S. and I.A.P.), as well as at the University of South Dakota, supported by the United States Department of Energy, Office of Science, Office of Basic Energy Sciences, Heavy Element Chemistry programme under award no. DE-SC0023022 (S.R.C. and B.V.) and by the high-performance computing systems at the University of South Dakota, funded by the National Science Foundation under award no. OAC-1626516 (S.R.C. and B.V.).