Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Organic Spectroscopy => Topic started by: Babcock_Hall on October 31, 2022, 11:36:35 AM
-
We recently resynthesizes a primary alcohol, which I discussed in a different thread. The two spectra were very similar, except for the following. The -CH2-OH group near 3.80 ppm was a triplet in the first synthesis but a slightly broadened quartet in the second synthesis. In the first synthesis a very broad signal appeared at 1.6 ppm. In the second synthesis we observed two very broad, non-Lorentzian signals, one at 2.5 and the other at 1.8 ppm. Our interest is in being certain that the two syntheses produced identical compounds.
In the past I have occasionally seen three-bond coupling between the HOR hydrogen and the hydrogens on the adjacent carbon, but not always. It is my understanding that the rate of exchange of HOR hydrogens is a function of any catalyst that might be present. We gave away the first batch to another laboratory; otherwise, we would perform an internal standard experiment.