1H and 13C-NMR Spectroscopic Study of Some 1H-4,5-Dihydroimidazolium Salts

Abstract

first_page settings Order Article Reprints Font Type: Arial Georgia Verdana Font Size: Aa Aa Aa Line Spacing:    Column Width:    Background: Open AccessAbstract 1H and 13C-NMR Spectroscopic Study of Some 1H-4,5-Dihydroimidazolium Salts by Alejandra Salerno and Isabel A. Perillo * Departamento de Química Orgánica. Facultad de Farmacia y Bioquímica. Universidad de Buenos Aires. Junín 956 (1113), Argentina * Author to whom correspondence should be addressed. Molecules 2000, 5(3), 479-480; https://doi.org/10.3390/50300479 Published: 22 March 2000 Download Download PDF Download PDF with Cover Download XML Versions Notes Abstract: The 1H y 13C-NMR spectra of some 1,3 and 1,2,3-trisubstituted 1H-4,5-dihydroimidazolium salts are analyzed. Introduction1H-4,5-Dihydroimidazolium salts are typical cyclic amidinium compounds where the cation is resonance stabilized and the positive charge can be delocalized either on the nitrogen atoms or on the C2:NMR spectra analysis and its comparison with the corresponding saturated compounds (imidazoli-dines 2), allows to reach conclusions about the contribution of such structures. Experimental1H and 13C NMR spectra were recorded on a Bruker MSL-300 spectrometer using deuterochloro-form as the solvent. Results and DiscussionThe 1H and 13C-NMR spectroscopic study of a series of 1,3-di and 1,2,3-trisubstituted 1H-4,5-dihydroimidazoliom salts 1 (Table) is presented. Table 1. Table 1. R1R2R3X-C6H5HC6H5Cl-p-CH3C6H4Hp-CH3C6H4Cl-p-Cl-C6H4HCH2-C6H5Cl-C6H5C6H5CH3I-p-CH3C6H4C6H5CH3I-p-CH3OC6H4C6H5CH3I-p-NO2C6H4C6H5CH3I- In order to assign the heterocyclic hydrogens and carbons in the 1,2-diaryl-3-methyl substituted compounds, the spectroscopic study of the parent 1H-4,5-dihydroimidazoles 3 and their salts 4 had been carried out.The unequivocal assignment of the hydrogen and carbon signals of the 1,2,3-trisubstituted salts has been done by the HMQC and HMBC spectra.The important electronic deficit at the level of the heterocyclic ring in compounds 1 has been clearly demonstrated by comparison of the spectroscopic features of the salts 1 with the corresponding imidazolidines 2. The iminium structure contribution (A,C) was analyzed according to the chemical shifts and the heteronuclear 1J13C-H coupling constants of the heterocyclic ring carbons and N-CH3. Share and Cite MDPI and ACS Style Salerno, A.; Perillo, I.A. 1H and 13C-NMR Spectroscopic Study of Some 1H-4,5-Dihydroimidazolium Salts. Molecules 2000, 5, 479-480. https://doi.org/10.3390/50300479 AMA Style Salerno A, Perillo IA. 1H and 13C-NMR Spectroscopic Study of Some 1H-4,5-Dihydroimidazolium Salts. Molecules. 2000; 5(3):479-480. https://doi.org/10.3390/50300479 Chicago/Turabian Style Salerno, Alejandra, and Isabel A. Perillo. 2000. "1H and 13C-NMR Spectroscopic Study of Some 1H-4,5-Dihydroimidazolium Salts" Molecules 5, no. 3: 479-480. https://doi.org/10.3390/50300479 Find Other Styles Article Metrics No No Article Access Statistics For more information on the journal statistics, click here. Multiple requests from the same IP address are counted as one view.