Tag Archives: spectral aliasing

Ultra-high-resolved NMR: Analysis of complex mixtures of compounds with near-identical 1H and 13C NMR spectra

Title: cover7Disentangling complex mixtures of compounds with near-identical 1H and 13C NMR spectra using pure shift NMR.
Authors: L. Castañar, R. Roldán, P. Clapés, A. Virgili and T. Parella.
Reference: Chem. Eur. J., 2015, 21, 7682-7685.
DOI: 10.1002/chem.201500521

 

Abstract: The thorough analysis of highly complex NMR spectra using pure shift NMR experiments is  described. The enhanced spectral resolution obtained from modern 2D HOBS experiments incorporating spectral aliasing in the 13C indirect dimension enables the distinction of similar compounds exhibiting near-identical 1H and 13C NMR spectra. It is shown that a complete set of extremely small Δδ(1H) and Δδ(13C) values, even below the natural line width (1 and 5 ppb, respectively), can be simultaneously determined and assigned.

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Pulse Programs Code for Bruker:

Data set Example:

 

PhD Thesis by Laura Castañar: Pulse Programs and Data Set Examples

Development and application of modern pure shift NMR techniques and improved HSQC/HSQMBC experiments

Presentación1

In the following links one can find Data Set Examples of each Publication presented in the Thesis Work, as well as the corresponding Pulse Program Code for Bruker. All 2D spectra have been previously phased and 2ii, 2ir, and 2ri files removed, otherwise data sets would be too big. Continue reading PhD Thesis by Laura Castañar: Pulse Programs and Data Set Examples

Ultra high-resolution HSQC

SeRMN seminar

  • Date:  Thursday 7th May, 2015
  • Hour: 15:30
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  Núria Marcó, SeRMN PhD Student

The content of our recently published article entitled “Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants” will be explained and discussed briefly. A rapid NMR data acquisition strategy in terms of enhanced resolution per time unit for the simple and efficient determination of multiple coupling constants is described. The use of 13C spectral aliasing combined with broadband 1H homodecoupling allows accurate measurements from ultra high resolved 2D HSQC cross-peaks.

Ultra HIgh Resolved HSQCportada

SeRMN presentation at the 56th ENC 2015 Conference

Imagen1

During these days takes place the 56th Experimental Nuclear Magnetic Resonance Conference (ENC) in Asilomar Conference Grounds (Pacific Grove, California, USA) where Laura Castañar presents an Oral Communication entitled “HOBS: Broadband Homonuclear Decoupled Band-Selective NMR Experiments with Full Sensitivity” Continue reading SeRMN presentation at the 56th ENC 2015 Conference

Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants

Journal cover: Chemical Communications“Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants” by Núria Marcó,  Andre Fredi and Teodor Parella. Chemical Communications 2015, 51:3262-3265. DOI: 10.1039/C4CC10279G

A rapid NMR data acquisition strategy in terms of enhanced resolution per time unit for the simple and efficient determination of multiple coupling constants is described. The use of 13C spectral aliasing combined with broadband 1H homodecoupling allows accurate measurements from ultra high resolved 2D HSQC cross-peaks.imagen4

 

Pulse Program Code for Bruker:

Data set Example:

Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra

CoverIssue“Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra” by Miriam Pérez-Trujillo, Laura Castañar, Eva Monteagudo, Lars T. Kuhn, Pau Nolis, Albert Virgili, R. Thomas Williamson and Teodor Parella. Chemical Communications  50:10214-10217 (2014). DOI: 10.1039/C4CC04077E

NMR-aided discrimination of enantiomers using chiral solvating agents (CSAs) is a well established method of enantiodifferentiation and measurement of enantiomeric ratios (er). The analysis is traditionally performed by observing chemical shift differences (ΔΔδ) in 1H signals by conventional 1D 1H NMR spectra. However, low ΔΔδ values and signal overlap caused by complex multiplets lead to the lack of spectral signal dispersion that preclude a straightforward analysis. Continue reading Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra