NMR and EPR Study of Homolysis of Diastereomeric Alkoxyamines

NMR and EPR Study of Homolysis of Diastereomeric Alkoxyamines Научная публикация

Журнал

Molecules
, E-ISSN: 1420-3049

Вых. Данные

Год: 2020, Том: 25, Номер: 21, DOI: 10.3390/molecules25215080

Ключевые слова

alkoxyamine; chirality; homolysis; imidazoline radical; kinetics; nitrogen inversion; nitroxide; nitroxide mediated polymerization; scavenger; stereoisomerization

Авторы

Cherkasov Sergey ^1,2 , Parkhomenko Dmitriy ¹ , Genaev Alexander ¹ , Salnikov Georgii ¹ , Edeleva Mariya ¹ , Morozov Denis ¹ , Rybalova Tatyana ¹ , Kirilyuk Igor ¹ , Marque Sylavain R.A. ³ , Bagryanskaya Elena ¹

Организации

1	N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Pr. Lavrentjeva 9, 630090 Novosibirsk, Russia
2	National Research University—Novosibirsk State University, 630090 Novosibirsk, Russia
3	Aix Marseille Univ, CNRS, ICR, UMR 7273, case 551, Avenue Escadrille Normandie-Niemen, 13397 Marseille CEDEX 20, France

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.

Cherkasov S. , Parkhomenko D. , Genaev A. , Salnikov G. , Edeleva M. , Morozov D. , Rybalova T. , Kirilyuk I. , Marque S.R.A. , Bagryanskaya E.
NMR and EPR Study of Homolysis of Diastereomeric Alkoxyamines

Molecules. 2020. V.25. N21. DOI: 10.3390/molecules25215080 WOS Scopus РИНЦ

Полный текст от издателя

Опубликована online:

1 нояб. 2020 г.

Web of science	WOS:000589192300001
Scopus	2-s2.0-85095391577
РИНЦ	45210247
OpenAlex	W3097201233