Parahydrogen-Induced Polarization in the Study of Rhodium(I)-Catalyzed Alkyne Hydrogenation: An Organometallic Undergraduate Laboratory Experiment

This upper-level undergraduate chemistry experiment involves the rhodium(I)-catalyzed hydrogenation of phenylacetylene to styrene using two different catalysts, which result in two different mechanisms of hydrogenation. Students were able to determine which of two mechanisms corresponded to two different hydrogenation catalysts using parahydrogen-induced polarization (PHIP), a technique rarely studied in the undergraduate laboratory, and a more traditional kinetic study that followed the uptake of hydrogen gas over time. This experiment also exposes students to the use of Schlenk lines, high-pressure gases, and cryogenic liquids, all of which are important tools in the organometallic chemist’s toolbox.