103Rh-NMR

Figure 2.2 103Rh NMR spectrum of mixtures of [RhCl Br6 ]3 species (n = 0-6 a denotes cis,/ac-isomer, b denotes trans,mer-isomer), (a-d) are varying Cl Br ratios in the starting material. (Reproduced with permission from Z. Naturforsch., Teil B, 1989, 44, 1402.)...

Bender et al. [19] used 103Rh-NMR chemical shift differences to demonstrate an electronic difference at rhodium between two diastereoisomers, and suggested that this might influence the crucial hydrogen addition step. 

An excellent example of the use of 31P chemical shifts, in combination with H-NMR and 103Rh-NMR data as well as coupling constants information, can be found in the report by Duckett et al. [21] on the activation of... 

These /6-aromatic complexes are not easily spotted by routine NMR measurements, as 31P-NMR data for aromatic and methanol complexes are very similar (Table 44.2). However, the two types of complexes can be distinguished unequivocally by using 103Rh-NMR spectroscopy [48,49]. 

The 103Rh isotope has 100% natural abundance and a spin of A, which makes it particularly suitable for NMR spectroscopy. An application of the technique has been the identification of 10 monomeric aquabromorhodium(III) species [RhBr (OH2)6 ] 3 n 1+, where n = 0-6 in aqueous solution (Read et al., 1992a). The same authors (Read et al., 1992b) also used 103Rh NMR to identify the presence of dimers and trimers of [Rh(H20)6]3+ and detected Rh-Rh coupling in the trimer. 

Ag2Rh6C(CO)15] IR, 13C, 103Rh NMR No Rh6 trigonal prism, with an interstitial C atom, and the two Rhj faces capped by Ag atoms 123... 

Temperature dependent 103Rh-NMR spectra of the Rh cluster show that the Rh skeleton is stereochemically non-rigid. At - 80 °C the spectrum is in agreement with the X-ray structure (3 doublets 1 4 4). At room temperature only one doublet is observed118. ... 

A review has been published on the applications of 103Rh NMR spectroscopy in structural chemistry.323 The complex [CpRh(dmpm)(HD)]+, where dmpm = bisdimethyldiphosphinomethane, gives a H 3IP) spectrum showing that it is a dihydrogen complex.324 High-pressure NMR spectroscopy was used to identify RhH(CO)(L)3 and RhH(CO)2(L)2 under 40 bar of CO/H2 (L = P... 

H and 13C ll NMR spectra for (N)-[I I3Ru3 C6I I5[CH(CH3)CH2)OH] (C6Me6)2(0)]+ show a strong intramolecular hydrogen bond between the p3-oxo cap and the hydroxyl function in acetone solution.346 ll, 13C and 15N chemical shifts were used to probe the coordination of substituted pyridines and aminides to Rh2(02CCF3)4.347 The H, 13C, 31P and 103Rh NMR spectra have been reported for phosphine-phosphonite ferrocenediyl dinuclear rhodium complexes.348 31P NMR data were able to discriminate between enantiomers... 

H- F NOESY and inverse 103Rh NMR were used to probe positional anion effects for [Rh(l,5-COD)(Biphemp)]X, where Biphemp = [(6,6 -dimethylbiphenyl)-2,... 

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