Resolution Rhenium

Rate-determining step, hydroformylation, 163 Reactivity, enantiomers, 286 Recognition, enantiomers, 278 Reduction and oxidation, 5 Reductive coupling, dissolving metal, 288 Reductive elimination, 5, 111 Resolution. See Kinetic resolution Rhenium-carbene complexes, 288 Rhodium-catalyzed hydrogenation, 17, 352 amino acid synthesis, 18, 352 BINAP, 20... 

Resolution, analysis complicated by insufficient, 201 of x-rays, 61, 113-115 Response time of multiplier phototube, 57 Rhenium, determination by x-ray emission spectrography, 328 Rhodium, determination by x-ray emission spectrography, 328 Risk, consumer, 215 producer, 215... 

Field emission microscopy was the first technique capable of imaging surfaces at resolution close to atomic dimensions. The pioneer in this area was E.W. Muller, who published the field emission microscope in 1936 and later the field ion microscope in 1951 [23]. Both techniques are limited to sharp tips of high melting metals (tungsten, rhenium, rhodium, iridium, and platinum), but have been extremely useful in exploring and understanding the properties of metal surfaces. We mention the structure of clean metal surfaces, defects, order/disorder phenomena,... 

Glaser oxidative coupling [Cu(OAc)2/py] of the rhenium ethynyls Re(C=CH)(NO)(PR3)Cp (R = Ph 248-250 tol, C6H4Bu -4251) affords the corresponding diyndiyls Re(NO)(PR3)Cp 2(p-C=CC=C) (96) as diaste-reotopic mixtures. Fractional crystallization leads to diastereotopic enrichment, or resolution for R = Ph, which permitted cystallographic assignment of the configuration. 13C-Labeled complexes were prepared and... 

Obviously, the 4f - 5 p crossing does not correspond to an electric dipole transition, but to an electric quadrupole moment. It has no clear-cut effect in photo-electron spectra of tungsten, rhenium and osmium, suggesting that the non-diagonal elements of the effective one-electron operator are smaller than 0.3 eV. It would be worthwhile to study volatile molecules such as WF6 or 0s04 under conditions of high resolution using either the continuous spectrum emitted by a synchrotron, or 132.3 eV photons from an yttrium anti-cathode (20, 21). 

Fig. 28 Resolution of a rhenium(I) tx base and its use in the formation of an enantio-enriched dihydronaphthalene...

The performance of the Mamyrin instrument can be appreciated from the mass spectrum of the isotopic cluster of rhenium bromide trimer ions shown in Figure 3.2, in which mass resolution exceeds 1 part in 3000. 

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