Halogens deuterium

J. Hubner (Denmark) Rev Sci Instrum 2001 72 229 Single-mode fiber core 9 pm, clad 125 pm/V>l = 0.12 material silica Deuterium halogen X = spectral None Fluorescence... 

S. M. Cramer (United States) J Chromatogr A2004 1,044 277 Multimode fiber core 600 pm, clad 630 pm AfA = 0.22 material silica Deuterium halogen X = spectral lOx objective Absorbance... 

The deuterium halogen lamp is a low-pressure gas discharge fight source often used in spectroscopy when a fuU-spectrum source of ihumination... 

LET measurement obtained fiom Deuterium-Halogen lamp produeed eonsistently lower values than those... 

LET test using Deuterium-Halogen fight source produce about 5% lower value compared to those from laser beam of equivalent wavelength. 

Figure 8 Comparison of the LET values obtained fiom laser beam soince and the Deuterium-Halogen source...

Azaindolizine, 5-chloro-nucleophilic substitution, 4, 458 8-Azaindolizine, 7-chloro-nucleophilic substitution, 4, 458 Azaindolizines basicity, 4, 454 electronic spectra, 4, 445 electrophilic substitution, 4, 453 halogenation, 4, 457 hydrogen/deuterium exchange, 4, 458 NMR, 4, 447, 449 nucleophilic attack, 4, 458 protonation, 4, 453 reaction with isothiocyanates, 4, 513 reactions, 5, 267 reviews, 4, 444 UV spectra, 4, 446, 449 Azaindolizines, amino-tautomerism, 4, 452... 

Imtdazo[4,5-c]pyridtne, 4,5,6,7-tetrahydro-synthesis, 5, 623, 640, 641 Imidazo[4,5-c]pyridine-6-carboxylic acid, 4,5,6,7-tetrahydro-synthesis, 5, 623, 641 Imidazopyridines as anthelmintic, 1, 202 synthesis, 5, 462 Imidazo[l,2-n]pyridines deuterium exchange, 5, 611 diazo coupling, 5, 614 Dimroth rearrangement, 5, 613 halogenation, 5, 611 hydrogenation, 5, 614 Mannich reaction, 5, 612 nitration, 5, 612 1-oxides... 

Beyer synthesis, 2, 474 electrolytic oxidation, 2, 325 7r-electron density calculations, 2, 316 1-electron reduction, 2, 282, 283 electrophilic halogenation, 2, 49 electrophilic substitution, 2, 49 Emmert reaction, 2, 276 food preservative, 1,411 free radical acylation, 2, 298 free radical alkylation, 2, 45, 295 free radical amidation, 2, 299 free radical arylation, 2, 295 Friedel-Crafts reactions, 2, 208 Friedlander synthesis, 2, 70, 443 fluorination, 2, 199 halogenation, 2, 40 hydrogenation, 2, 45, 284-285, 327 hydrogen-deuterium exchange, 2, 196, 286 hydroxylation, 2, 325 iodination, 2, 202, 320 ionization constants, 2, 172 IR spectra, 2, 18 lithiation, 2, 267... 

There are three methods which are commonly used in the steroid field to replace a halogen atom by deuterium. These methods involve treatment of the halides— generally chloride, bromide or iodide—(a) with lithium aluminum deuteride, (b) with deuterium gas and a surface catalyst or (c) with zinc in O-deuterated acids or alcohols. 

Displacement of aromatic halogen in 2,4-diiodo-estradiol with tritiated Raney nickel yields 2,4-ditritiated estradiol. Aromatic halogen can also be replaced by heating the substrate with zinc in acetic acid-OD or by deuteration with palladium-on-charcoal in a mixture of dioxane-deuterium oxide-triethylamine, but examples are lacking for the application of these reactions in the steroid field. Deuteration of the bridge-head position in norbornane is readily accomplished in high isotopic purity by treatment of the... 

Quadrupole coupling constants for molecules are usually determined from the hyperfine structure of pure rotational spectra or from electric-beam and magnetic-beam resonance spectroscopies. Nuclear magnetic resonance, electron spin resonance and Mossbauer spectroscopies are also routes to the property. There is a large amount of experimental data for and halogen-substituted molecules. Less data is available for deuterium because the nuclear quadrupole is small. 

Problem 10.10 How might you replace a halogen substituent by a deuterium atom if you wanted to prepare a deuterated compound ... 

Furthermore, if an aldehyde or ketone is treated with D O. the acidic a hydrogens are replaced by deuterium. For a given ketone, the rate of deuterium exchange is identical to the rate of halogenation, implying that a common intermediate is involved in both processes. 

Durch Reduktion von Halogen-aromaten mit Natrium-tetradeuterido-borat/Palla-dium(II)-chlorid in Methanol-O-D konnen deuterierte Aromaten hergestellt werden. Der Deuterium-Gehalt der letzteren ist hoher als 95% ... 

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