Analysis of purity of common solvents using quantitative NMR

CHED 269

Peter T. Bell, Alyssa D. Adkins, and Linda D. Schultz, schultz@tarleton.edu. Department of Chemistry, Geosciences, & Environmental Science, Tarleton State University, Box T-0540, Stephenville, TX 76402
Although some of the earliest applications of Nuclear Magnetic Resonance Spectroscopy involved quantitative analysis of mixtures, NMR is currently regarded primarily as a qualitative tool for the elucidation of molecular structures. However, quantitative NMR, qNMR, is regaining recognition as an analytical technique. The purity of many common solvents can be determined rapidly, at the per cent level, by an internal standard method using 1-H NMR in D2O solvent. This procedure is of particular interest for checking the purity of compounds with a tendency to absorb atmospheric water. Solvents analyzed in this manner include acetone, ethyl alcohol, methyl alcohol, tetrahydrofuran, and N,N-dimethylformamide.