Abstract by Jacob Davis
Chemistry and Biochemistry
IR spectroscopy of bimetallic catalysts
It is known that the catalysis reaction we are studying occurs under photochemical conditions in which the boron replaces a hydrogen of a benzene to produce a borylated arene. Even though the reaction is confirmed to occur, the mechanism is unknown and calculations indicate that previously proposed mechanisms are energetically unfavorable. Our preliminary data suggest the loss of a CO ligand off the Iron, but the actual intermediate has yet to be observed and it remains unconfirmed whether it is the CO-Fe or the Fe-Cu bond that is cleaved upon photolysis.
Our objective has been to discover the mechanism whereby such catalytic borylation reactions occur. We have been using time-resolved FT-IR spectroscopy to observe intermediates, along with DFT computations done by Dr. Ess, to deduce a reasonable mechanism. Our hypothesis has been that one of the carbonyl ligands of the catalyst is dissociated upon photolysis, after which a Benzene solvent molecule is coordinated to the metal which then reacts with the boron species to produce a borylated arene.