I’m just going to leave this here, for the next time I (or anyone else) want to determine the in-tube concentration of an NMR sample.[1,2]
Solvent | [Residual] in mM |
Acetic Acid-d4 | 27.1 |
Acetone-d6 | 2.30 |
Acetonitrile-d3 | 13.1 |
Benzene-d6 | 9.52 |
Chloroform-d | 25.1 |
Dimethylsulfoxide-d6 | 2.38 |
Methanol-d4 | 12.7 |
Pyridine-d4 | 14.8 |
Tetrahydrofuran-d8 | 7.78 |
Toluene-d8 | 5.94 |
Water-d2 | 145 |
Values are derived from this formula:
1000*(1-X)*d/(MW*Y)
x = the posted deuterium purity (ie. “99.8%” CDCl3)
y= number of hydrogen/deterium atoms per molecule.
d = density of the deutero solvent.
MW for residual solvent (ex. CHD3O for methanol)
[1] Low concentration samples can be calculated by using the 13C satellite bands, which are 1/200 the concentration of the standard residual peak.
[2] For water, rinse the NMR tube, vial, etc. with D2O prior to dissolving your sample.