The DEPTQ+ Experiment: Leveling the DEPT Signal Intensities and Clean Spectral Editing for Determining CHn Multiplicities
Abstract
:1. Introduction
2. Results and Discussion
2.1. Theory
2.1.1. Original DEPTQ Pulse Sequence
Quaternary Carbons
ICH2 = Cx [0.35 sin2(2πJCHδ) − 1.00 sin4(πJCHδ)]
ICH3 = Cx [0.53 sin2(2πJCHδ) cos2(πJCHδ) − 0.75 sin2(2πJCHδ) sin2(πJCHδ) + 1.06
sin6(πJCHδ)]
ICH2 = −1.00 Cx
ICH3 = +1.06 Cx
ICH2 = Cx [0.35 sin2(2πJCHδ)]
ICH3 = Cx [2.11 sin2(πJCHδ) cos4(πJCHδ)]
ICH2 = 0
ICH3 = 0
ICH2 = Cx [0.35 sin2(2πJCHδ) − 1.00 sin4(πJCHδ)] − Cx [0.35 sin2(2πJCHδ)] = −Cx
sin4(πJCHδ)
ICH3 = Cx [0.53 sin2(2πJCHδ) cos2(πJCHδ) − 0.75 sin2(2πJCHδ) sin2(πJCHδ) + 1.06
sin6(πJCHδ)] − Cx [2.11 sin2(πJCHδ) cos4(πJCHδ)]
ICH3 = +1.06 Cx
2.1.2. The DEPTQ+ Pulse Sequence
Quaternary Carbons
ICH2 = Cx [0.71 sin(πJCHδ1) cos(πJCHδ2) sin(2πJCHδ3) − 1.00 sin(πJCHδ1) sin(πJCHδ2)
sin2(πJCHδ3)]
ICH3 = Cx [−2.11 sin(πJCHδ1) cos2(πJCHδ2) sin(πJCHδ3) cos2(πJCHδ3) + 3 sin(πJCHδ1)
cos(πJCHδ2) sin(πJCHδ2) cos(πJCHδ3) sin2(πJCHδ3) − 1.06 sin(πJCHδ1) sin2(πJCHδ2)
sin3(πJCHδ3)]
ICH2 = −Cx [0.71 sin (πJCHδ1) cos (πJCHδ2) sin (2πJCHδ3)]
ICH3 = −Cx [2.11 sin (πJCHδ1) cos2(πJCHδ2) sin (πJCHδ3) cos2(πJCHδ3)]
2.2. Experimental Results
2.2.1. Cholesteryl Acetate
2.2.2. 4-Methyl-N,N-di(prop-2-yn-1-yl)aniline
2.3. Practical Aspects
3. Materials and Methods
3.1. Synthesis and Characterization of 4-Methyl-N,N-di(prop-2-yn-1-yl)aniline
3.2. NMR Measurements
3.3. Numerical Simulations
3.4. NMR Simulations
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Conflicts of Interest
Sample Availability
References
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DEPTQ | DEPTQ+ | |
---|---|---|
CH groups | sin2(πJCHδ) | sin(πJCHδ1) sin(πJCHδ3) |
CH2 groups | sin4(πJCHδ) | sin(πJCHδ1) sin(πJCHδ2) sin2(πJCHδ3) |
CH3 groups | sin6(πJCHδ) | sin(πJCHδ1) sin2(πJCHδ2) sin3(πJCHδ3) |
Experiment | Angle θ | Amplitude of CH | Amplitude of CH2 | Amplitude of CH3 |
---|---|---|---|---|
DEPTQ+ | 45° | −0.71 | 1 | −1.06 |
DEPTQ | 0.71 | 1 | 1.06 | |
DEPTQ+ | 90° | −1 | 0 | 0 |
DEPTQ | 1 | 0 | 0 | |
DEPTQ+ | 135° | −0.71 | −1 | −1.06 |
DEPTQ | 0.71 | −1 | 1.06 |
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Bigler, P.; Melendez, C.; Furrer, J. The DEPTQ+ Experiment: Leveling the DEPT Signal Intensities and Clean Spectral Editing for Determining CHn Multiplicities. Molecules 2021, 26, 3490. https://doi.org/10.3390/molecules26123490
Bigler P, Melendez C, Furrer J. The DEPTQ+ Experiment: Leveling the DEPT Signal Intensities and Clean Spectral Editing for Determining CHn Multiplicities. Molecules. 2021; 26(12):3490. https://doi.org/10.3390/molecules26123490
Chicago/Turabian StyleBigler, Peter, Camilo Melendez, and Julien Furrer. 2021. "The DEPTQ+ Experiment: Leveling the DEPT Signal Intensities and Clean Spectral Editing for Determining CHn Multiplicities" Molecules 26, no. 12: 3490. https://doi.org/10.3390/molecules26123490