Carbon-13 nuclear magnetic resonance spectroscopic data

There follows a discussion of proton nuclear magnetic resonance ( H NMR), carbon nuclear magnetic resonance ( C NMR), and mass spectrometry (MS) of the Narcissus alkaloids. A list of the different Narcissus alkaloids, their spectroscopic properties, and literature with the most recent spectroscopic data is given in Table X. 

Several spectroscopic techniques, namely, Ultraviolet-Visible Spectroscopy (UV-Vis), Infrared (IR), Nuclear Magnetic Resonance (NMR), etc., have been used for understanding the mechanism of solvent-extraction processes and identification of extracted species. Berthon et al. reviewed the use of NMR techniques in solvent-extraction studies for monoamides, malonamides, picolinamides, and TBP (116, 117). NMR spectroscopy was used as a tool to identify the structural parameters that control selectivity and efficiency of extraction of metal ions. 13C NMR relaxation-time data were used to determine the distances between the carbon atoms of the monoamide ligands and the actinides centers. The II, 2H, and 13C NMR spectra analysis of the solvent organic phases indicated malonamide dimer formation at low concentrations. However, at higher ligand concentrations, micelle formation was observed. NMR studies were also used to understand nitric acid extraction mechanisms. Before obtaining conformational information from 13C relaxation times, the stoichiometries of the... 

The hydrocarbon ("oil") fraction of a coal pyrolysis tar prepared by open column liquid chromatography (LC) was separated into 16 subfractions by a second LC procedure. Low voltage mass spectrometry (MS), infrared spectroscopy (IR), and proton (PMR) as well as carbon-13 nuclear magnetic resonance spectrometry (CMR) were performed on the first 13 subfractions. Computerized multivariate analysis procedures such as factor analysis followed by canonical correlation techniques were used to extract the overlapping information from the analytical data. Subsequent evaluation of the integrated analytical data revealed chemical information which could not have been obtained readily from the individual spectroscopic techniques. The approach described is generally applicable to multisource analytical data on pyrolysis oils and other complex mixtures. 

The chemical structure of pergolide mesylate was determined from the data of synthetic method, elemental analysis, ultraviolet (UV) spectra, infrared (IR) absorption spectra, hydrogen ( H) and carbon ( C) nuclear magnetic resonance (NMR) spectra, and mass spectra. The following is a summary discussion of the spectroscopic data and potential isomerism of pergolide mesylate to support the confirmation of structure of this compound. ... 

In this chapter, you will employ jointly all of the spectroscopic methods we have discussed so far to solve stractural problems in organic chemistry. Forty-five problems are provided to give you practice in applying the principles learned in earlier chapters. The problems involve analysis of the mass spectrum (MS), the infrared (IR) spectrum, and proton and carbon ( H and nuclear magnetic resonance (NMR). Ultraviolet (UV) spectral data, if provided in the problem, appear in a tabular form rather than as a spectrum. You will notice as you proceed through this chapter that the problems use different mixes of spectral information. Thus, you may be provided with a mass spectrum, an infrared spectrum, and a proton NMR spectrum in one problem, and in another you may have available the infrared spectrum and both proton and carbon NMR. 

The range of spectroscopic techniques now available means that it is often a straightforward matter to arrive at a possible structure for a new isocoumarin. Key references are given in the Tables relating to the structure elucidation of the natural isocoumarins. Carbon-13 nuclear magnetic resonance spectroscopy has proved to be of use in determination of the structures of the more complex isocoumarins 139). The C-NMR data for some simple isocoumarin derivatives have been listed (227, 265). 

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