Reactions in nitroimidazole triggered by low-energy (0-2 eV) electrons: methylation at N1-H completely blocks reactivity

Angew Chem Int Ed Engl. 2014 Nov 3;53(45):12240-3. doi: 10.1002/anie.201407452. Epub 2014 Sep 15.

Abstract

Low-energy electrons (LEEs) at energies of less than 2 eV effectively decompose 4-nitroimidazole (4NI) by dissociative electron attachment (DEA). The reactions include simple bond cleavages but also complex reactions involving multiple bond cleavages and formation of new molecules. Both simple and complex reactions are associated with pronounced sharp features in the anionic yields, which are interpreted as vibrational Feshbach resonances acting as effective doorways for DEA. The remarkably rich chemistry of 4NI is completely blocked in 1-methyl-4-nitroimidazole (Me4NI), that is, upon methylation of 4NI at the N1 site. These remarkable results have also implications for the development of nitroimidazole based radiosensitizers in tumor radiation therapy.

Keywords: gas-phase reactions; low-energy electrons; mass spectrometry; metastable compounds; reaction mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Methylation
  • Nitroimidazoles / chemistry*

Substances

  • Nitroimidazoles