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p-Anisidine (or para-anisidine) is an organic compound with the formula CH 3 OC 6 H 4 NH 2. A white solid, commercial samples can appear grey-brown owing to air oxidation. It is one of three isomers of anisidine, methoxy-containing anilines. It is prepared by reduction of 4-nitroanisole. [8]
15 N NMR is the most effective method for investigation of structure of heterocycles with a high content of nitrogen atoms (tetrazoles, triazines and their annelated analogs). [7] [8] 15 N labeling followed by analysis of 13 C– 15 N and 1 H– 15 N couplings may be used for establishing structures and chemical transformations of nitrogen ...
Benzylidene acetal is a protecting group in synthetic organic chemistry of the form PhCH(OR) 2. For example, 4,6-O-benzylidene-glucopyranose is a glucose derivative. Benzylidene is an archaic term for compounds of the type PhCHX 2 and PhCH= substituents (Ph = C 6 H 5). For example, dibenzylideneacetone is (PhCH=CH) 2 CO.
The difference between the chemical shift of a given nucleus in a diamagnetic vs. a paramagnetic environment is called the hyperfine shift.In solution the isotropic hyperfine chemical shift for nickelocene is −255 ppm, which is the difference between the observed shift (ca. −260 ppm) and the shift observed for a diamagnetic analogue ferrocene (ca. 5 ppm).
Nuclear magnetic resonance crystallography (NMR crystallography) is a method which utilizes primarily NMR spectroscopy to determine the structure of solid materials on the atomic scale. Thus, solid-state NMR spectroscopy would be used primarily, possibly supplemented by quantum chemistry calculations (e.g. density functional theory ), [ 1 ...
The NMR data includes 1 H, 13 C, 11 B, 15 N, 17 O, 19 F, 29 Si, and 31 P. The data were in the form of graphically displayed line lists. The data were in the form of graphically displayed line lists. Access to the database could be purchased piecemeal or leased as the entire library through individual or group contracts.
Triple resonance experiments are a set of multi-dimensional nuclear magnetic resonance spectroscopy (NMR) experiments that link three types of atomic nuclei, most typically consisting of 1 H, 15 N and 13 C. These experiments are often used to assign specific resonance signals to specific atoms in an isotopically-enriched protein.
In solid-state NMR spectroscopy, magic-angle spinning (MAS) is a technique routinely used to produce better resolution NMR spectra. MAS NMR consists in spinning the sample (usually at a frequency of 1 to 130 kHz ) at the magic angle θ m (ca. 54.74°, where cos 2 θ m =1/3) with respect to the direction of the magnetic field .