Keto-Enol Equilibrium from NMR Data:A Closer Look at the Laboratory Experiment

摘要

NMR spectroscopy can be advantageously used in physico-chemical laboratory experiments for teaching students basicsof this method as well as principles of kinetics and equilibriumexperimental setups. Rich information on molecular proper-ties obtained from NMR spectra along with the sufficientlyaccurate data on the composition of a reaction mixture allowsone to evaluate thermodynamic parameters of a chemical reac-tion as well as to interpret them from a molecular point of viewemploying elements of statistical thermodynamics and quantummechanical calculations. A student is thus confronted with ex-perimental material that can be analyzed within several theoreticconcepts. The equilibrium between the keto and enol forms ofacetylacetone (Hacac = 2,4-pentanedione),