The 2D 13C INADEQUATE method provides double quantum - single quantum (DQ/SQ) correlations and enables one to determine the carbon - carbon skeleton of small organic molecules. The method is quite insensitive for 13C since the natural abundance of 13C is only 1.1% and the chance of having two adjacent 13C nuclei is only 1 in 8264. For spins other than 13C, for which the natural abundance is high, one expects the sensitivity of DQ/SQ correlation spectroscopy to be much higher. 11B has a natural abundance of 80.42% and the chance of having two adjacent 11B nuclei in compounds with boron-boron bonds is 1 in 1.55. 11B NMR spectra are often sufficiently broad due to efficient quadrupolar relaxation such that homonuclear 11B - 11B J coupling is unresolved however the T2's are long enough to allow the collection of 2D 11 B COSY and 2D DQ/SQ data. The figure below shows the 2D 11B DQ/SQ correlation spectrum of ortho-carborane. The 11B bonding connectivity can be determined easily from the spectrum.
Two-dimensional NMR lineshape analysis of single, multiple, zero and double quantum correlation experiments
Two-dimensional NMR lineshape analysis of single, multiple, zero and double quantum correlation experiments
Abstract
NMR spectroscopy provides a powerful approach for the characterisation of chemical exchange and molecular interactions by analysis of series of experiments acquired over the course of a titration measurement. The appearance of NMR resonances undergoing chemical exchange depends on the frequency difference relative to the rate of exchange, and in the case of one-dimensional experiments chemical exchange regimes are well established...
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02-29-2020 09:52 PM
[NMR paper] 3D 14N/1H Double Quantum/1H Single Quantum Correlation Solid-State NMR for Probing Parallel and Anti-Parallel Beta-Sheet Arrangement of Oligo-Peptides at Natural Abundance.
3D 14N/1H Double Quantum/1H Single Quantum Correlation Solid-State NMR for Probing Parallel and Anti-Parallel Beta-Sheet Arrangement of Oligo-Peptides at Natural Abundance.
Related Articles 3D 14N/1H Double Quantum/1H Single Quantum Correlation Solid-State NMR for Probing Parallel and Anti-Parallel Beta-Sheet Arrangement of Oligo-Peptides at Natural Abundance.
Chemphyschem. 2018 May 08;:
Authors: Hong YL, Asakura T, Nishiyama Y
Abstract
?-sheet structure of oligo- and poly-peptides can be formed in anti-parallel (AP)- and...
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05-09-2018 02:49 AM
[NMR paper] A Different Approach to Multiplicity-Edited Heteronuclear Single Quantum Correlation Spectroscopy
A Different Approach to Multiplicity-Edited Heteronuclear Single Quantum Correlation Spectroscopy
Publication date: Available online 8 August 2015
Source:Journal of Magnetic Resonance</br>
Author(s): Peyman Sakhaii, Wolfgang Bermel</br>
A new experiment for recording multiplicity-edited HSQC spectra is presented. In standard multiplicity-edited HSQC experiments, the amplitude of CH2 signals is negative compared to those of CH and CH3 groups. We propose to reverse the sign of 13C frequencies of CH2 groups in t1 as criteria for editing. Basically, a modified r,x...
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Rapid Heteronuclear Single Quantum Correlation NMR Spectra at Natural Abundance
Rapid Heteronuclear Single Quantum Correlation NMR Spectra at Natural Abundance
David Schulze-Su?nninghausen, Johanna Becker and Burkhard Luy
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja411588d/aop/images/medium/ja-2013-11588d_0005.gif
Journal of the American Chemical Society
DOI: 10.1021/ja411588d
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/TExWpxpxjak
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Origin and removal of mixed-phase artifacts in gradient sensitivity enhanced heteronuclear single quantum correlation spectra
Origin and removal of mixed-phase artifacts in gradient sensitivity enhanced heteronuclear single quantum correlation spectra
Abstract Here we describe phasing anomalies observed in gradient sensitivity enhanced 15N-1H HSQC spectra, and analyze their origin. It is shown that, as a result of 15N off-resonance effects, dispersive contributions to the 1H signal become detectable, and lead to 15N-offset dependent phase errors. Strategies that effectively suppress these artifacts are presented.
Content Type Journal Article
Category Article
Pages 199-207
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09-30-2011 08:01 PM
Characteristics of zero-quantum correlation spectroscopy in MAS NMR experiments.
Characteristics of zero-quantum correlation spectroscopy in MAS NMR experiments.
Characteristics of zero-quantum correlation spectroscopy in MAS NMR experiments.
J Magn Reson. 2010 Dec;207(2):197-205
Authors: Köneke SG, van Beek JD, Ernst M, Meier BH
Zero-quantum coherence generation and reconversion in magic-angle spinning solid-state NMR is analyzed. Two methods are discussed based on implementations using symmetry-based pulse sequences that utilize either isotropic J couplings or dipolar couplings. In either case, the decoupling of abundant...
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03-18-2011 06:00 PM
[NMR paper] Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Related Articles Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Annu Rev Phys Chem. 2003;54:531-71
Authors: Drobny GP, Long JR, Karlsson T, Shaw W, Popham J, Oyler N, Bower P, Stringer J, Gregory D, Mehta M, Stayton PS
Proteins directly control the nucleation and growth of biominerals, but the details of molecular recognition at the protein-biomineral interface remain poorly understood. The elucidation of recognition...
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11-24-2010 08:49 PM
Double quantum filtering homonuclear MAS NMR correlation spectra: a tool for membrane protein studies
Double quantum filtering homonuclear MAS NMR correlation spectra: a tool for membrane protein studies
Jakob J. Lopez, Christoph Kaiser, Sarika Shastri and Clemens Glaubitz
Journal of Biomolecular NMR; 2008; 41(2) pp 97 - 104
Abstract:
13C homonuclear correlation spectra based on proton driven spin diffusion (PDSD) are becoming increasingly important for obtaining distance constraints from multiply labeled biomolecules by MAS NMR. One particular challenging situation arises when such constraints are to be obtained from spectra with a large natural abundance signal background which...