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Deuterated solvents are a group of compounds where one or more hydrogen atoms are substituted by deuterium atoms. These isotopologues of common solvents are often used in nuclear magnetic resonance spectroscopy .
Deuterium NMR has a range of chemical shift similar to proton NMR but with poor resolution, due to the smaller magnitude of the magnetic dipole moment of the deuteron relative to the proton. It may be used to verify the effectiveness of deuteration: a deuterated compound will show a strong peak in 2 H NMR but not proton NMR.
The chemical shifts of a molecule change slightly between solvents, and therefore the solvent used is almost always reported with chemical shifts. [ citation needed ] Proton NMR spectra are often calibrated against the known solvent residual proton peak [ 16 ] as an internal standard instead of adding tetramethylsilane (TMS), which is ...
Deuterium is often represented by the chemical symbol D. Since it is an isotope of hydrogen with mass number 2, it is also represented by 2 H. IUPAC allows both D and 2 H, though 2 H is preferred. [8] A distinct chemical symbol is used for convenience because of the isotope's common use in various scientific processes.
Deuterated chloroform is a general purpose NMR solvent, as it is not very chemically reactive and unlikely to exchange its deuterium with its solute, [9] and its low boiling point allows for easy sample recovery. It, however, it is incompatible with strongly basic, nucleophilic, or reducing analytes, including many organometallic compounds.
13 C NMR Spectrum of DMSO-d 6. Pure deuterated DMSO shows no peaks in 1 H NMR spectroscopy and as a result is commonly used as an NMR solvent. [2] However commercially available samples are not 100% pure and a residual DMSO-d 5 1 H NMR signal is observed at 2.50ppm (quintet, J HD =1.9Hz). The 13 C chemical shift of DMSO-d 6 is 39.52ppm (septet ...
Where small signals are observed in a 1 H NMR spectrum of a highly deuterated sample, these are referred to as residual signals. They can be used to calculate the level of deuteration in a molecule. Analogous signals are not observed in 2 H NMR spectra because of the low sensitivity of this technique compared to the 1 H analysis. Deuterons ...
Occasionally, small peaks can be seen shouldering the main 1 H NMR peaks. These peaks are not the result of proton-proton coupling, but result from the coupling of 1 H atoms to an adjoining carbon-13 (13 C) atom. These small peaks are known as carbon satellites as they are small and appear around the main 1 H peak i.e. satellite (around) to