Solution-state NMR studies

Sachleben J R ef a/1998 Solution-state NMR studies of the surface structure and dynamics of semiconductor nanocrystals J. Phys. Chem. B 102 10 117... 

Marcotte I, Auger M (2005) Bicelles as model membranes for solid- and solution-state NMR studies of membrane peptides and proteins. Concept Magn Reson A 24A 17-37... 

Some of the zwitterionic A557-silicates described in this chapter were studied for their chemical properties. As shown for 32,44, and 45 in Scheme 7, compounds of this particular formula type undergo an intermolecular exchange of their benzene-1,2-diolato(2-) ligands in solution at room temperature.38 Solution-state NMR studies ([D6]DMSO XH, 13C, 29Si) and FD MS experiments provided evidence for the equilibrium 32 + 44 2 45. 

Solution-state NMR studies (XH, 13C, 19F, 29Si) at room temperature have shown that the zwitterions 94-104 are also present in solution. The 29Si chemical shifts were found to be very similar to the isotropic 29Si chemical... 

Solution-state NMR studies suggest that the catalysts containing l- and D-Pro adopt p-turns and p-hairpins in solution,respectively. Reactions exhibit first-order dependence on catalyst 24, consistent with a monomeric catalyst in the ratedetermining step of the reaction. These catalysts exhibit enantiospecific rate acceleration, in comparison to the reaction rate when NMI is employed as catalyst. An isosteric replacement of an alkene for a backbone amide in a tetrapeptide catalyst (catalysts 32 and 33, Fig. 4) has lent credence to a proposed mechanism of rate acceleration [31). While catalyst 32 exhibits a fcrei=28 with substrate 27, alkene-containing catalyst 33 is not selective in this kinetic resolution and also affords a reduced reaction rate. This suggests that the prolyl amide is kinetically significant in the stereochemistry-determining step of the reaction. 

Dissolved organic matter (DOM) is ideally suited to solution-state NMR studies because, by definition, DOM is soluble. Considering that modern solution-state NMR generally produces higher resolution spectra than does solid-state NMR and... 

Harris, R. K. (1983). Solution-state NMR studies of Group IV elements (other than carbon). NATO ASI Series, Series C Mathematical and Physical Sciences, 103 (Multinucl. Approach NMR Spectrosc.), 343-359. 

Most NMR spectroscopists have on some occasion examined the Periodic Table of NMR-active nuclei with 13C, I70, etc., and contemplated that at first glance essentially the whole Periodic Table is potentially open to study by NMR. Solution-state NMR studies of nuclei with small magnetic moments exist, but often when papers report data concerning such nuclei the information is obtained not by simple direct excitation but indirectly using polarization transfer techniques such as INEPT and DEPT, and/or by using reverse detection methods.1 As many of these indirect methods are not available in the... 

Quantitative solution-state NMR studies can be very important for bioinorganic studies because the active species cannot often be characterized by other means in solution (15, 32, 35, 36). 

Syntheses and Solution-State NMR Studies of Zwitterionic Spirocyclic X Si-Organosilicates Containing Two Identical Unsymmetrically Substituted l,2-Benzenediolato(2-) Ligands... 

Solution-state NMR studies of mercury complexes are most meaningful when taken under slow-exchange conditions. Fast-exchange spectra involving equilibria between several species in solution are common due to the relatively high lability... 

Reactions of the 5 c6>-cubane 3 with chalcogens were also investigated. While mono-chalcogenides are readily produced in the case of sulfur, selenium and tellurium, further reaction with either sulfur or selenium produced only insoluble products. The solid-state structures of the mono-selenide and mono-telluride 65a and 65b (Scheme 2.2.14) revealed that one of the Sn(N Bu)2(NH Bu) sites was oxidized in preference to the unique Sn(N Bu)(NH Bu)2 tin center. Solution-state NMR studies indicated that chalcogen exchange occurs exclusively between the two Sn(N Bu)2(NH Bu) sites. In the case of selenium, in addition to 65a, the selenido-bridged dimer 66 was present in solution as indicated by /sn-Se coupling constants (65a, 3220 Hz 66, 779 Hz). 

Strauss HM, Hughes J, Schmieder P (2005) Heteronuclear solution-state NMR studies of the chromophore in cyanobacterial phytochrome Cphl. Biochemistry 44 8244—8250... 

The present review concentrates on the uses of nitrogen NMR studies in the structural investigations of peptides and similar compounds. Many of the molecules of interest are insufficiently soluble to permit solution-state NMR studies and thus solid-state measurements are the method of necessity. An... 

An alternative route to the formation of poly(imide)s is the nitro-displace-ment reaction to form the Ultem series of polymers, first exploited by White et al. [11] at General Electric. These, and similar materials, have application in composite materials and as specialty thermoplastics. Compared to the amic acid route described above, the nitro-displacement reaction is highly controlled, and materials of high chemical regularity produced, as demonstrated by White et al. [11] in their solution-state NMR study of Ultem poly(imide)s. 

H AND SOLUTION-STATE NMR OF IRRADIATED POLYMERS 3.1. Solution-state NMR studies of cross-linking... 

Lipid structure and dynamics of lipids are very important in understanding cellular function. Solid- and solution-state NMR studies of a variety of different lipids have been studied here by a variety of different NMR techniques. ... 

SOLUTION-STATE NMR STUDIES OF GROUP IV ELEMENTS (OTHER THAN CARBON)... 

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