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The details of an experiment that includes the synthesis of an imidazolium salt are presented. Reports show that stable N-heterocyclic carbenes (NHCs) have become a key class of ligands in organometallic chemistry since their isolation and crystallographic characterization by Arduengo et al. The results of the experiment are also discussed.

An experiment, designed for undergraduate, to synthesize a six-membered Cyclopalladated complex by activation of a C aliphatic -H bond is described. This experiment shows that certain organometallic complexes are stable enough to be obtained in acetic acid, using reflux, in the absence of an inert gas atmosphere.

Students in a third-year organometallic chemistry course can learn from using an experiment that involves carbonyl-stabilized ylides, but an observation of the synthesis related to keto-enol tautomers in a carbonyl phosphonium salt is of interest. When the students had access to a 250-MHz Fourier transform NMR spectrometer, the proton spectra for the first step of the synthesis showed a species other than the dominant one. The new species has a doublet at 4.44 ppm coming from J(PH)20 Hz and an O(ital.H) peak at 12.6, but it may be shifted by up to 0.5 ppm in samples. Other data are given and will allow students to better discuss the resonance structures.