1H and 13C spectral assignment of 1,4,5,6,7,8‐hexahydroquinolines and their oxa‐analogues 5,6,7,8‐tetrahydro‐4H‐chromenes

NMR study of 1,4-dihydropyridine derivatives endowed with long alkyl and functionalized chains

“…These findings have been accounted for by the strong push-pull effect of the groups linked to the olefinic double bonds, similar to that previously observed in other related molecules. [8][9][10][11] The alkoxycarbonyl sp 2 -carbon (COOR or COOR 1 ) on C-3 and C-5 appears at 166-167 ppm. In compounds 1c, 2a, 3c, 4a, 5a and 6a the cyano group appears at ca.119 ppm.…”

“…These data are of interest to determine the effect that this substitution pattern has on the chemical shifts of the 1,4-DHPs ring and to complete the reference data on the previously reported related systems. 8,11…”

1H and 13C spectral assignment of 2(1H)‐pyridone derivatives

“…In the 19 F NMR spectrum, the fluorine nuclei form a complex system centered at 138.3, 153.1 and 158.7 ppm, which cannot be resolved in order to calculate the corresponding coupling constants.…”

“…These findings have been accounted for by the strong push-pull effect of the groups linked to the olefinic double bonds, similarly to that observed previously in other related molecules. 19,20 Since we have achieved unambiguous assignments for all the 1 H NMR resonances, 13 C NMR resonances were assigned in a straightforward manner by analysis of the HMQC spectra 705 Spectral Assignments and Reference Data for the protonated carbon atoms on the basis of chemical shift theory, substituent effects and DEPT data. Quaternary carbons were assigned by analysis of the HMBC spectra.…”

One‐step synthesis of aminopyrimidines from 5‐Oxo‐4H‐benzopyrans

“…Therefore, we have reported the synthesis of a wide variety of 4H-pyran derivatives [10][11][12] as well as their study by mass spectrometry [13,14] and NMR spectroscopy [15,16]. Therefore, we have reported the synthesis of a wide variety of 4H-pyran derivatives [10][11][12] as well as their study by mass spectrometry [13,14] and NMR spectroscopy [15,16].…”