A1 Journal article (refereed)
Noncovalent Modulation of Chemoselectivity in the Gas Phase Leads to a Switchover in Reaction Type from Heterolytic to Homolytic to Electrocyclic Cleavage (2023)

Nau, W. M., Moorthy, S., Lambert, H., Mohan, N., Schwarzlose, T., Kalenius, E., & Lee, T.-C. (2023). Noncovalent Modulation of Chemoselectivity in the Gas Phase Leads to a Switchover in Reaction Type from Heterolytic to Homolytic to Electrocyclic Cleavage. Angewandte Chemie, 62(32), Article e202303491. https://doi.org/10.1002/anie.202303491

JYU authors or editors

Publication details

All authors or editors: Nau, Werner M.; Moorthy, Suresh; Lambert, Hugues; Mohan, Neetha; Schwarzlose, Thomas; Kalenius, Elina; Lee, Tung-Chun

Journal or series: Angewandte Chemie

ISSN: 1433-7851

eISSN: 1521-3773

Publication year: 2023

Publication date: 10/05/2023

Volume: 62

Issue number: 32

Article number: e202303491

Publisher: Wiley

Publication country: Germany

Publication language: English

DOI: https://doi.org/10.1002/anie.202303491

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/89309

Abstract

In the gas phase, thermal activation of supramolecular assemblies such as host-guest complexes leads commonly to noncovalent dissociation into the individual components. Chemical reactions, for example of encapsulated guest molecules, are only found in exceptional cases. As observed by mass spectrometry, when 1-amino-methyl-2,3-diazabicyclo[2.2.2]oct-2-ene (DBOA) is complexed by the macrocycle b-cyclodextrin, its protonated complex undergoes collision-induced dissociation into its components, the conventional reaction pathway. Inside the macrocyclic cavity of cucurbit[7]uril (CB7), a competitive chemical reaction of monoprotonated DBOA takes place upon thermal activation, namely a stepwise homolytic covalent bond cleavage with the elimination of N2, while the doubly protonated CB7•DBOA complex undergoes an inner-phase elimination of ethylene, a concerted, electrocyclic ring-opening reaction. These chemical reaction pathways stand in contrast to the gas-phase chemistry of uncomplexed monoprotonated DBOA, for which an elimination of NH3 predominates upon collision-induced activation, as a heterolytic bond cleavage reaction. The combined results, which can be rationalized in terms of organic-chemical reaction mechanisms and density-function theoretical calculations, demonstrate that chemical reactions in the gas phase can be steered chemoselectively through noncovalent interactions.

Keywords: supramolecular chemistry; mass spectrometry

Free keywords: mass spectrometry; cucurbiturils; reactivity modulation; gas-phase chemistry; host-guest complexes

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2023

JUFO rating: 3