NMR and EPR Study of Homolysis of Diastereomeric Alkoxyamines

Sergey Cherkasov, Dmitriy Parkhomenko, Alexander Genaev, Georgii Salnikov, Mariya Edeleva, Denis Morozov, Tatyana Rybalova, Igor Kirilyuk, Sylvain R.A. Marque, Elena Bagryanskaya

Research output: Contribution to journalArticlepeer-review

Abstract

Three alkoxyamines based on imidazoline radicals with a pyridine functional group-potential initiators of nitroxide-mediated, controlled radical polymerization-were synthesized. Electron Paramagnetic Resonance (EPR) measurements reveal biexponential kinetics for the thermolysis for diastereomeric alkoxyamines and monoexponential kinetics for an achiral alkoxyamine. For comparison, the thermolysis of all three alkoxyamines was studied by NMR in the presence of three different scavengers, namely tetramethylpiperidine-N-oxyl (TEMPO), thiophenol (PhSH), and β-mercaptoethanol (BME), and detailed analysis of products was performed. NMR differentiates between N-inversion, epimerization, and homolysis reactions. The choice of scavenger is crucial for making a reliable and accurate estimate of the true homolysis rate constant.

Original languageEnglish
Article number5080
Number of pages20
JournalMolecules (Basel, Switzerland)
Volume25
Issue number21
DOIs
Publication statusPublished - 1 Nov 2020

Keywords

  • alkoxyamine
  • chirality
  • homolysis
  • imidazoline radical
  • kinetics
  • nitrogen inversion
  • nitroxide
  • nitroxide mediated polymerization
  • scavenger
  • stereoisomerization
  • MODEL ALKOXYAMINES
  • LIMITATIONS
  • NITROXIDES
  • DECOMPOSITION
  • IMIDAZOLINE
  • CONTROL AGENTS
  • N-O
  • SYSTEMS
  • RADICAL POLYMERIZATION
  • C-ON BOND

Fingerprint

Dive into the research topics of 'NMR and EPR Study of Homolysis of Diastereomeric Alkoxyamines'. Together they form a unique fingerprint.

Cite this