Catalytic Arene H/D Exchange with Novel Rhodium and Iridium Complexes
journal contributionposted on 2012-03-12, 00:00 authored by Jennifer L. Rhinehart, Kimberly A. Manbeck, Sara K. Buzak, Geoffrey M. Lippa, William W. Brennessel, Karen I. Goldberg, William D. Jones
Three novel pendant acetate complexes, [Rh(bdmpza)Cl3]−M+, [Rh(bdmpza)Cl2(py)], and [Ir(bdmpza)Cl3]−M+ (bdmpza = bis(3,5-dimethylpyrazol-1-yl) acetate, M+ = Li+, Na+), were synthesized. Abstraction of halide from these complexes with silver salts yielded species capable of C–H activation of arenes. The catalytic H/D exchange reaction between benzene and trifluoroacetic acid-d was optimized, and these conditions were used to evaluate H/D exchange in other arenes. Branched alkyl substituents in alkyl aromatics showed an affinity toward deuterium exchange in the β-alkyl position only. DFT calculations were performed to determine the mechanism of H/D exchange.