Study of E/Z isomerization of (arylamino)methylidenefuran-2(3H)-ones by 1 H, 13 C, 15 N spectroscopy and DFT calculations in different solvents

Alexander K Osipov; Alexander A Anis'kov; Vyacheslav S Grinev; Alevtina Yu Yegorova

doi:10.1002/mrc.4583

Study of E/Z isomerization of (arylamino)methylidenefuran-2(3H)-ones by ¹ H, ¹³ C, ¹⁵ N spectroscopy and DFT calculations in different solvents

Magn Reson Chem. 2017 Aug;55(8):730-737. doi: 10.1002/mrc.4583. Epub 2017 Mar 20.

Authors

Alexander K Osipov, Alexander A Anis'kov¹, Vyacheslav S Grinev^{1

2}, Alevtina Yu Yegorova¹

Affiliations

¹ Institute of Chemistry, National Research Saratov State University, Astrakhanskaya St., 83, Saratov, 410012, Russia.
² Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prospekt Entuziastov, Saratov, 410049, Russia.

PMID: 28181284
DOI: 10.1002/mrc.4583

Abstract

The structure and configuration of the series of previously unknown arylaminomethylidenefuran-2(3H)-ones have been determined in solution by ¹ H, ¹³ C, ¹⁵ N nuclear magnetic resonance spectroscopy including two-dimensional experiments such as ¹ H─¹ H COSY, dqCOSY, ¹ H─¹³ C HSQC, ¹ H─¹³ C HMBC. It was found that synthesized substances exist as an equilibrium mixture of E- and Z-enamines in solution. It was established on the basis of density functional theory calculations that the exchange between the two push-pull enamines is a simple rotation around an exocyclic partial double bond that depends on the effect of the solvents. Copyright © 2017 John Wiley & Sons, Ltd.

Keywords: E/Z isomerization; arylaminomethylene derivatives of furanones; condensation; configuration; furan-2(3H)-ones; push-pull olefins; triethyl orthoformate.