Assigning the ESI mass spectra of organometallic and coordination compounds

Abstract

Electrospray ionization mass spectrometry (ESI‐MS) is a useful technique for solving organometallic and coordination chemistry characterization problems that are difficult to address using traditional methods. However, assigning the ESI mass spectra of such compounds can be challenging, and the considerations involved in doing so are quite different from assigning the mass spectra of purely organic samples. This is a tutorial article for organometallic/coordination chemists using ESI‐MS to analyze pure compounds or reaction mixtures. The fundamentals of assigning ESI mass spectra are discussed within the context of organometallic and coordination systems. The types of ions commonly observed by ESI‐MS are categorized and described. Finally, a step‐by‐step guide for the assignment of organometallic and coordination chemistry ESI mass spectra is provided along with two case studies.

Synthesis, Characterization, and Non-Covalent Interactions of Palladium(II)-Amino Acid Complexes

“…High–resolution time-of-flight mass spectrometry performed on a sample taken directly from the reaction mixture clearly showed the formation of a bis-methionine compound ( Figure 16 ). HRMS is extremely useful in the characterization of any compound, but especially for palladium complexes [ 26 ]. In addition to obtaining the exact mass of fragments that allow for a clear determination of stoichiometry, the fragmentation patterns uniquely identify palladium compounds.…”

“…Molecules 2021, 26,4331 various C-N stretching modes of the free guanidine group. These absorptions ar in both the free ligand and the complex (Figure 22) and support the premise that nine side chain is not involved in coordination with the metal.…”

Selectivity control in thiol–yne click reactions via visible light induced associative electron upconversion

“…1A). 36 For this experiment, we have synthesized alkyne 1q with an easily ionized sulfonate group and carried out the thiol-yne reaction between alkyne 1q and 2-chlorothiophenol 2d under standard reaction conditions (Scheme 4). In the negative ion mode in the absence of green light irradiation, the signals corresponding to alkyne 1q, thiol 2d, and Eosin Y species were dominant in the ESI mass spectra.…”

Disulfonated xantphos for mass spectrometric mechanistic analysis

“…The spectrum looks more complicated than expected for a clean compound, but combinations of the dianion and the sodium cation and trace oxidation readily account for nearly all species. 42 The exception is a small amount of triply sulfonated xantphos at m/z 272. In order to examine the reactivity of ions using ESI-MS, we employ pressurized sample infusion (PSI) to monitor the reactions continuously in real-time.…”