The carbon-13 NMR spectra of six carbenoid complexes of the type (OC) 5Cr-(CXX′) have been recorded. The carbenoid carbon atoms are all markedly deshielded (chemical shifts vs. TMS in the range −271 to −360). With only one minor inversion of uncertain significance, the chemical ...
Carbon-13 NMRis the application ofnuclear magnetic resonancewith respect tocarbon. It is analogous toproton NMRand allows the identification of carbon atoms in an organic molecule just as proton NMR identifies hydrogen atoms. As such carbon NMR is an important tool in structure elucidation inorganic...
However the most interesting feature of these spectra were the long range 13C-31P couplings. With the zig-zag 'II' system of the trans isomer the coupling is transmitted over up to six Carbon-13 NMR spectra of carotenoids 101 Table 2. "C-NMR datafor the e-end oflutein and related ...
Chapter NMR in Chemistry pp 84-107 Carbon-13 NMR Spectra William KempAffiliated withHeriot-Watt University Abstract The chemical shift range of carbon-13 resonances is so wide (more than 200 ppm for simple functional classes) that most compounds show a separate signal for each different ...
Chang, C.: Carbon-l3-Proton Long-Range Couplings of Phenols. Hydrogen Bonding and Stercospecificity. J. Org. Chem. 41, 1881 (1976). Article CAS Google Scholar Pachler, K. G. R., and P. L. Wessels: Selective Population Inversion (Spi). A Pulsed Double Resonance Method in FT Nmr Spe...
The 1H and 13C NMR spectra of three aromatic ketimines with varying degrees of fluoro substitution have been extensively studied using one and two dimensional techniques. COSY experiments were conducted to identify the protons on each of the aromatic groups, HETCORR experiments were then utilized ...
The reason why the "residual dispersion component phenomenon" is common for FT NMR of nuclei with a wide range of chemical shifts, but not with proton FT NMR, is discussed. The "residual dispersion component phenomenon" can be obviated by exponential apodization, by extended zero filling or ...
Intrinsic carbon-13 NMR solvent shifts in hydrocarbons. Relevance of long range substituent parameters 喜欢 0 阅读量: 16 作者:ARN Wilson,LJMVD Ven,JWD Haan 摘要: Carbon-13 NMR chemical shifts have been measured in a number of binary mixtures of normal alkanes. Intrinsic solvent shifts are ...
The carbon-13 NMR spectra of the novel rearranged hopanes, spergulagenin-A and related triterpenoids, and 21α-Hopanes, mollugogenol-A, mollugogenol-G diacetate and related compounds, were recorded. Their analyses were aided by the chemical shifts of some model compounds and by the change in ...
(a) Powder XRD patterns ofh-BCN synthesized with different amount of glucose, (b) solid-state13C NMR spectrum of BCN-30, (c) Raman spectra of theh-BN, BCN-30 and the physical mixture ofh-BN and graphite, (d) EELS spectra of BCN-xsample, (e) ultraviolet–visible diffuse reflectance...