Synthesis and Utility of Neptunium(III) Hydrocarbyl Complex

To extend organoactinide chemistry beyond uranium, reported here is the first structurally characterized transuranic hydrocarbyl complex, Npη⁴‐Me₂NC(H)C₆H₅]₃ ( 1 ), from reaction of NpCl₄(DME)₂ with four equivalents of KMe₂NC(H)C₆H₅]. Unlike the U^III species, the neptunium analogue can be used to access other Np^III complexes. The reaction of 1 with three equivalents of HE₂C(2,6‐Mes₂‐C₆H₃) (E=O, S) yields (2,6‐Mes₂‐C₆H₃)CE₂]₃Np(THF)₂, maintaining the trivalent oxidation state.