NMR-Based Kinetic Experiments for Undergraduate Chemistry Laboratories

Abstract

The dehydration reaction of 1,1-diphenylpropan-1-ol and a series of 1,1-diphenylethan-1-ol derivatives can be followed by 1H NMR spectroscopy. The reaction conveniently occurs at room temperature in CDCl3 using trichloroacetic acid or trifluoroacetic acid. The kinetic experiments are suitable for a variety of courses and center on the use of NMR spectroscopy to follow reaction progress, establish reaction order with respect to each component, examine temperature dependence, and explore structure-reactivity relationships. Many of the kinetic studies described can be investigated using a 60 MHz FT-NMR although higher-field instruments are necessary for accurate initial rate studies for establishing the order of the reaction.