Conversion of a UO₂²⁺ Precursor to UH⁺ and U⁺ Using Tandem Mass Spectrometry to Remove Both "yl" Oxo Ligands

Multiple-stage collision-induced dissociation (CID) of a uranyl propiolate cation, [UO2(O2C-C equivalent to CH)](+), can be used to prepare the U-methylidyne species [O=U equivalent to CH](+) [J. Am. Soc. Mass Spectrom. 2019, 30, 796-805]. Here, we report that CID of [O=U CH](+) causes elimination of CO to create [UH](+), followed by a loss of H-center dot to generate U+. A feasible, multiple-step pathway for the generation of [UH]+ was identified using DFT calculations. These results provide the first demonstration that multiple-stage CID can be used to prepare both U+ and UH+ directly from a UO22+ precursor for the subsequent investigation of ion-molecule reactivity.