In this study, various trifluoro β-diketones are explored using density functional theory and 19F Nuclear Magnetic Resonance (NMR) in four aprotic solvents with wide-ranging polarities. The ΔG° of tautomerization (diketone ⇌ enol) of each compound was calculated both experimentally and computationally. By examining how structural features of unique fluorinated β-diketones in different solvent environments affect diketone ⇌ enol equilibrium, students can develop a direct link between molecular structure and thermodynamic behavior. Students also evaluate the chemical accuracy of their computational results, which helps them understand both the power and limitations of computational chemistry. Furthermore, it challenges them to critically think about how model reliability may depend on molecular structure and solvent environment. This experiment is easily accessible and adaptable to a wide range of courses (organic chemistry, physical chemistry, computational chemistry, and advanced instrumental analysis) due to the simplicity, cost, and availability of the compounds. This laboratory module is pedagogically effective because it integrates hands-on spectroscopic analysis using straightforward 19F NMR data, applies thermodynamic analysis to real chemical systems, and uses readily available computational tools to interpret experimental results. Overall, the laboratory module promotes active learning, cross-disciplinary thinking, and deeper student understanding of tautomerization and thermodynamics.
Petion et al. (Thu,) studied this question.