Carbon-13 magnetic resonance

A yield of 5.8 g. (877o), m.p. 280-282°, was obtained by the submitters. The infrared spectrum, proton and carbon-13 magnetic resonance spectra, and mass spectrum of the product were identical to those of an authentic sample of 1-adamantanol. A mixed melting point with an authentic sample of 1-adamantanol showed no depression. 

Pesek, J.J. and Mason, W.R. (1979) Carbon-13 magnetic resonance spectra of diamagnetic cyano complexes. Inorganic Chemistry, 18, 924—928. 

Carbon-13 magnetic resonance (CMR) can play a useful role. Since carbon magnetic resonance deals with analyzing the carbon distribution types, the obvious structural parameter to be determined is the aromaticity, fa Direct determination from the various types of carbon environments is one of the better methods for the determination of aromaticity. Thus, through a combination of proton and carbon magnetic resonance techniques, refinements can be made on the structural parameters, and for the solid-state high-resolution carbon magnetic resonance technique, additional structural parameters can be obtained. 

Use of Carbon-13 Magnetic Resonance Spectroscopy for Biosynthetic Investigations A. G. 

Carbon-13 magnetic resonance spectra of the naturally occurring cytidines have been described in several papers.79-82 The electronic structure of the compounds is reflected in the carbon-13 shifts. For instance, the observed chemical shifts for these and other pyrimidine and purine nucleosides were correlated, at least qualitatively, with the calculated charge densities (see Section VIII) and with the known reactivity of these molecules. It is difficult to draw conclusions from the carbon-13 spectra about the tautomerism of cytosine. 

Carbon-13 magnetic resonance studies have been made only on 1-carbethoxy-5-trifluoroacetyl-1H-pyrindine (26d).56 The chemical shifts of the ring carbons are as follows 137.5, 136.7, 134.1, 131.0, 1.30.0, 112.7, 107.8, and 105.0 ppm. 

Along similar lines, carbon-13 magnetic resonance has been applied to coal and to the elucidation of the character of soluble coal fractions and other coal-derived materials (Bartuska et ah, 1978 Ladner and Snape, 1978 Miknis, 1988). In fact, it is the advances in carbon-13 magnetic resonance that have brought new thoughts to the chemical nature of, and structural types in, coal. The technique brought with it the innovative solid-state techniques that allowed coal to be viewed in its natural solid state without invoking the criterion of sample solubility. This removed the need for dissolution of coal fractions and the often... 

Kiezel, L., Liszka, M., and Rutkowski, M., Carbon-13 magnetic resonance spectra of benzothiophene and dibenzothiophene, Spec. Lett., 12, 45, 1979. 

Nuclear magnetic resonance (NMR) spectroscopy (Section 14.1) A type of spectroscopy that uses transitions between the energy states of certain nuclei when they are in a magnetic field to supply information about the hydrocarbon part of a compound. There are two NMR techniques that are of most use to organic chemists proton magnetic resonance (lH-NMR) spectroscopy, which provides information about the hydrogens in a compound, and carbon-13 magnetic resonance spectroscopy (13C-NMR), which provides information about the carbons in a compound. 

Chenon M-T, Pugmire RJ, Grant DM, Panzica RP, Tbwnsend LB (1975) Carbon-13 magnetic resonance. XXVI. A quantitative determination of the tautomeric population of certain purines. J Am Chem Soc 97 4636 - 4642... 

Using carbon-13 magnetic resonance spectroscopy, Rinehart and his collaborators have shown49 that the biosynthesis of the streptovaricins is very similar to that of the rifamycins. Streptovaricin D is synthesized from a C7N unit of unknown origin to which 8 propionic acid residues and two acetic acid residues are attached, whereby the direction of growth is the same as that of the rifamycins. In contrast to the... 

Carbon-13 magnetic resonance studies have been made on imidazole and its corresponding anion and cation.241-243 Linear relationships have been found243 between the 13C and proton chemical shifts and the Hiickel 7r-electron densities in diazoles and triazoles. 

Other physical and spectral properties of the histrionicotoxins are presented in Table III. Proton and carbon-13 magnetic resonance assignments have been presented (57-59) and reviewed (5). For proton spectra, see Refs. 3,57-59 for carbon-13 assignments, see Ref. 55. The diagnostic infrared peaks for various histrionicotoxins in solution have been tabulated... 

VI. For details of the mass spectra, see Refs. 3, 73, 96, and 127. For proton and carbon-13 magnetic resonance spectra data, see Refs. 76 and 96 and references to synthetic material cited in Ref. 5. For FTIR spectra, see Ref. 

VII. Proton and carbon-13 magnetic resonance spectral data have been reported (77,78,87). The proton assignments for 235B reported in Ref. 87 are for the hydrochloride salt, and the chemical shift for H-15 is 5.31 ppm (not 5.81 as reported). Impurities were included in the integration between... 

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