Intramolecular hydrogen bonds in 1, 4-dihydropyridine derivatives. Issue 6 (13th June 2018)

• Record Type: Journal Article
• Authors: Petrova, M.; Muhamadejev, R.; Vigante, B.; Duburs, G.; Liepinsh, Edvards
• Is Part Of: Royal Society open science. Volume 5:Issue 6(2018)
• Publication Date: 2018-06-13
• Subjects: NMR -- DFT -- 1 -- 4-dihydropyridines -- hydrogen bond -- H/D 13C isotope effects -- IR; Science -- Periodicals; 500
• DOI: 10.1098/rsos.180088
• Languages: English
• ISSNs: 2054-5703

Abstract

Abstract : 1, 4-Dihydropyridine (1, 4-DHP) derivatives have been synthesized and characterized by 1 H, 13 C, 15 N nuclear magnetic resonance (NMR) spectroscopy, secondary proton/deuterium 13 C isotope shifts, variable temperature 1 H NMR experiments and quantum-chemical calculation. The intramolecular hydrogen bonds NH⋯O=C and CH⋯O=C in these compounds were established by NMR and quantum-chemical studies The downfield shift of the NH proton, accompanied by the upfield shift of the 15 N nuclear magnetic resonance signals, the shift to the higher wavenumbers of the NH stretching vibration in the infrared spectra and the increase of the 1 J( 15 N, 1 H) values may indicate the shortening of the N–H bond length upon intramolecular NH⋯O=C hydrogen bond formation.