A new type of pincer-iridium catalyst for dehydrogenation and related reactions of alkanes (2013)
Undergraduate: Shunzhi Wang
Faculty Advisor: Maurice Brookhart
Department: Chemistry
The project focuses on synthesizing and examining the mechanism of a new class of alkane dehydrogenation catalysts based on triptycenepincer Iridium (Ir) ligand (sp3 hybridized). Although several (PCP)Ir- and (POCOP)Ir- based catalyst complex have already been synthesized, diverse (pincer)Ir catalysts show very different effectiveness and regioselectivity for varied co-catalysts and reactions. Our design of new dehydrogenation catalysts is guided partly by an exploratory density functional theory (DFT) study tailoring ligand design to affect metal-based properties. A series of (iPrPC(sp3)P)Ir triptycene-type catalysts were obtained from substituted anthracene derivatives through Diels-Alder reactions and their structures were verified with nuclear magnetic resonance (NMR) spectroscopy. These ligands are expected to improve catalytic activity, as they possess labile deformed C(sp3)-Metal bond as well as excellent thermal stability. Currently, the author is studying model reactions catalyzed by the developed system and conducting mechanistic studies to explore possible catalytic pathways and intermediates.