NMR multinuclear

Jameson C J and Mason J 1987 The chemical shift Multinuclear NMR ed J Mason (New York Plenum) oh 3... 

Everett, T. S. Multinuclear NMR Spectral Identification of Organofiuor-ine Compounds unpublished data. 

Raman and multinuclear NMR spectroscopy have been used to study the reaction product of pentafluoropyridine with XeF+AsF6 in anhydrous HF. Identified in the mixture was a fluoro(pentafluoropyridine)xenon(II) cation with the Xe bonded to the ring N (88CC257). 

In general, the carbohydrate-organotin(IV) complexes have been studied by and or, especially by multinuclear NMR ( Sn, H, and... 

The acid-base interaction in group 13-stibine and -bismuthine adducts seems to be very weak as is indicated by mass spectroscopic studies, which never showed the molecular ion peak but only the respective Lewis acid and Lewis base fragments. The extreme lability in the gas phase may also account for the fact that there are only very few reports on thermodynamic data of group 13-stibine or bismuthine adducts in the literature. Therefore, multinuclear NMR spectroscopy and single crystal X-ray diffraction are the most important analytical tools for the characterization of such adducts. 

The tveak and reversible binding of these complexes to calf-thymus DNA (ct DNA) suggests a dominant electrostatic mode of interaction nevertheless, relevant conformational distortions of the double helix are caused [50]. A multinuclear NMR study of the reactivity of [Au(en)Cl2]Cl and [Au(en)2]Cl3 vith guanosine 5 -monopho-sphate (5 -GMP) reveals that in an aqueous solution only [Au(en)Cl2]Cl binds very weakly to 5 -GMP via N(7) to give a 1 1 adduct [48]. 

Byabartta, P. (2007) Gold(l)-gold(III)-4,4 -bpy-phosphrne complexes synthesis and multinuclear NMR study. Transition Metal Chemistry, 32, 314. 

Bebout DC, Berry SM (2006) Probing Mercury Complex Speciation with Multinuclear NMR 120 81-105... 

The structures of doubly bonded compounds containing tin readily lend themselves to study by multinuclear NMR spectroscopy, as tin has two NMR active isotopes ll7Sn and ll9Sn. The chemical shifts of doubly bonded tin species in the 119Sn NMR spectrum cover a broad range from 6 = -150 to +835 (Table VI) however, the majority of the signals occur at low field S = 400 or above. 

Multinuclear NMR experiments showed two different types of BF3 groups, one BF3 group being coordinated with the tin atom and two equivalent ones with the nitrogen atoms. Further studies led to the conclusion that BF3 is initially bound to the tin atom at low molar ratios of BF3 to SniNR. The same authors were able to demonstrate that even base—stabilized SnCl2 can be bound to BF3. Thus, in F3B SnCij - NMe3 e.g. a base and a Lewis acid are simultaneously coordinated with the tin atom140). 

Reaction of [Ircp Cl2]2 with AgBF4 and (SPPh2)3CH in CH2C12 or Me2CO to which Et3N is added yields [Ircp ( 73-(SPPh2)3C]BF4, which has been structurally characterized.271 The Irm complexes [Ircp L3](PF6)2 (L3 = MeC(CFl2ER)3, E = Se, R = Me E = Te, R = Me, Ph) have been prepared and characterized by IR and multinuclear NMR spectroscopy.647... 

Zinc boryloxides with a tetrameric Zn404 core (45) have only recently been characterized. The single-crystal X-ray structure and multinuclear NMR spectroscopy studies were used as a basis for discussion of deformation of the central core.435 Alkali metal zinc orthoborates MZn4(B03)3 (M = K, Rb, Cs) have been synthesized and single-crystal X-ray structures determined for M = K and Rb.436... 

The simplest possible coordination compounds of Cd and Hg with chalcogen donors are the anions MCh22. Multinuclear NMR studies of these species (Ch = Se, Te) in NH3 or en solutions with [K(2.2.2-cryptand)]+ counterions have been reported.314 Structural studies31, also combined with new multinuclear NMR measurements, have been performed.316... 

Independently, triangulo-Hg3 compounds with stabilizing chelating diphosphine and diarsine ligands have been prepared, 82-387 crystal-structure analyses have been solved (the Hg—Hg bonds, 280 pm, are longer than before), and careful multinuclear NMR spectra measured and analysed. 

Routine identification and analytical characterization of all types of NHPs was preferably carried out by multinuclear NMR spectroscopy. Of particularly high diagnostic value are 31P NMR spectra where rather specific chemical shift ranges for heterocycles with different types of P-substituents can be observed. The largest chemical shifts occur for anionic and neutral 1,3,2-diazaphospholes (220-300 ppm) and 1,3,2-diazaphospholenium cations (210-200 ppm). Chemical shifts of P-halogen-l,3,2-diazaphospholenes vary over an overall range of 200-110 ppm and decrease in the order I (205-190 ppm)>Br (194-185 ppm two compounds... 

In a search for CVD precursors for beryllium, the air sensitive, volatile solid CpBe(SiMe3) 17 was prepared from the reaction of Li[SiMe3] with CpBeCl in pentane.62 Characterized with single crystal X-ray diffraction, multinuclear NMR, and mass spectra, the compound displays a Be-Si bond length of 2.185(2) A that is somewhat longer than the sum of covalent radii (2.01 A). The lengthening is similar to that observed in the related Be(Si(/-Bu)3)2 (Be-Si = 2.193(1) A),63 so there is not a pronounced effect from the Cp ligand on the Be-Si interaction. 

In addition to the influence of neighbors on 29Si chemical shifts, the geometrical effects (such as Si-O-T angles) already described above are also evident of mixed frameworks with elements other than Si on tetrahedral positions. This is reflected by the broadness of the bars shown in Fig. 1. Multinuclear NMR investigations on a large set of sodalite structures with various framework compositions show that T-O-T bond angle (T = Si, Al, Ga) and dTT distance chemical shift dependences exist, and mutual correlations between chemical shift of these NMR nuclei can be observed [68],... 

One difficulty with many synthetic preparations of semiconductor NCs that complicates any interpretation of NMR results is the inevitable distribution of sizes (and exact shapes or surface morphologies). Therefore attempts to make semiconductors as a sort of molecular cluster having a well-defined stoichiometry are of interest to learn potentially about size-dependent NMR parameters and other properties. One approach is to confine the semiconductor inside a template, for instance the cuboctahedral cages of the sodalite framework or other zeolite structures, which have been characterized by multinuclear NMR methods [345-347], including the mesoporous channel material MCM-41 [341, 348]. 

Multinuclear NMR data have been recorded for molsidomine 12 and its metabolite SIN-1 13, confirming that both are closed ring structures and that the positive charge is accommodated at the N3 position <1996CHE1358>. The c C4-C5 coupling constants for selected 1,2,3-oxadiazoles lie between 69.4 and 89 Hz, but correlation of these values with measures of bond order and aromaticity is difficult due to substituent effects <2000MRC617, 2002JST269>. 

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