The IsoMS project focused on development of mass-spectrometry tools for studying reaction mechanisms. The pressure gap between the formation of reaction intermediates in solution and their gas-phase detection is one of the biggest questions in mass spectrometric approach to study reactions. To tackle this question, we have designed Delayed reactant labeling (DRL) method. We have shown that this method can be used to track reaction kinetics of intermediates in gold(I) catalyzed reactions (e.g. Chem. Sci. 2020, 11, 980) or in palladium-catalyzed reactions (Organometallics 2017, 36, 2072). In addition, we have developed a coupling of mass spectrometry with a flow reactor for monitoring reaction kinetics in solution (Angew. Chem. Int. Ed. 2021, 60, 7126 and Chem. Methods 2021, 1, 430). This approach is suitable for monitoring reactive, short-lived intermediates. We have highlighted our approached in an invited review (Chem. Sci. 2020, 11, 11960).
The second part of IsoMS was devoted to the implementing of ion spectroscopy as an analytical tool. We have shown that helium tagging infrared photodissociation (IRPD) spectroscopy can be used to characterize reactive hypervalent metal complexes (e.g. J. Am. Chem. Soc. 2017, 139, 2757 or Chem. Commun. 2017, 53, 8786). We have cooperated with several leading laboratories in bioinorganic and organometallic chemistry on further dissemination of this method and broadening of its analytical scope (e.g. Nat. Commun. 2019, 10, 901 or Angew. Chem. Int. Ed. 2021, 60, 23018). We have also used the IRPD approach to characterize short lived intermediates in photochemical reactions (e.g. Angew. Chem. Int. Ed. 2019, 58, 15412). The approach is summarized in an invited review (ChemBioChem. 2020, 21, 2232).
Another part of IsoMS was devoted to probing of chemical reactivity in our low temperature trap. We have made a breakthrough in the investigation of the prototypical system FeO+ + H2 for which we were able to measure the rate constants down to 5 K (ChemPhysChem. 2016, 17, 3723). We have also investigated photochemical reactions in the cold trap using irradiation in the vis and UV spectral range (J. Mol. Spec. 2017, 332, 52). For example, we have rationalized temperature dependent formation of iron(V)-nitrido complexes by investigating spin state dependent photofragmentation of iron(II) azide complexes (Angew. Chem. Int. Ed. 2017, 56, 14057).
In general, IsoMS project significantly contributed to the methods to bridge the gap between solution chemistry and mass spectrometry detection of species from the solution. IsoMS also fulfilled the goal to use ion spectroscopy as an analytical tool. The method is used in the field of metal chemistry and belongs to ultimate tools to detect highly reactive species. The project brought various methods developments in the field of kinetics, flow chemistry, gas-phase reactions and detections of highly reactive species in metal chemistry and in photochemistry.
