Xiaoying Liu
Olefins are one of the primary starting materials in industrial synthesis and polymer and material sciences, and the fact that they exhibit diverse reactivities toward a set of transformations makes them a class of fundamental reactants. we are interested in the reaction mechanisms of the coupling between olefins and other small building blocks such as O- and N- containing units to form carbon-heteroatom bonds. In our studies, small units, for example O, NH, NR and CR2, are first prepared on the surfaces of noble metals including gold and silver. They are then coupled with olefins to form a series of products as a result of cycloaddition to the C=C double bond and/or nucleophilic attack of the carbon atoms. Two groups of olefins are studied, namely non-allylic and allylic olefins depending on if they have allylic hydrogens. They show different reaction activities as allylic hydrogens can also be activated in these reactions.
Temperature-programmed reaction spectra (TPRS) are used to identify the gaseous reaction products as well as to analyze the reaction kinetics. High-resolution electron energy loss spectroscopy (HREELS), in conjunction with Auger electron spectroscopy (AES) is used to characterize the structures of the reaction intermediates. These studies on metal surfaces provide rich information for understanding the mechanisms of these reactions and predicting the reactivities of the functionalization of olefins.