是1997年JOC上的文章: J. Org. Chem. 1997, 62, 7512-7515 NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities Hugo E. Gottlieb,* Vadim Kotlyar, and Abraham Nudelman* Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel Received June 27, 1997 In the course of the routine use of NMR as an aid for organic chemistry, a day-to-day problem is the identifica- tion of signals deriving from common contaminants (water, solvents, stabilizers, oils) in less-than-analyti- cally-pure samples. This data may be available in the literature, but the time involved in searching for it may be considerable. Another issue is the concentration dependence of chemical shifts (especially 1H); results obtained two or three decades ago usually refer to much more concentrated samples, and run at lower magnetic fields, than today’s practice. We therefore decided to collect 1H and 13C chemical shifts of what are, in our experience, the most popular “extra peaks” in a variety of commonly used NMR solvents, in the hope that this will be of assistance to the practicing chemist.
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