@article{frasco_mukherjee_sommer_perry_lambic_abboud_jakubikoya_ison_2016, title={Nondirected C-H Activation of Arenes with Cp*Ir(III) Acetate Complexes: An Experimental and Computational Study}, volume={35}, ISSN={["1520-6041"]}, DOI={10.1021/acs.organomet.6b00308}, abstractNote={Combined experimental and computational studies have revealed factors that influence the nondirected C–H activation in Cp*Ir complexes that contain carboxylate ligands. A two-step acetate-assisted pathway was shown to be operational where the first step involves substrate binding and the second step involves cleavage of the C–H bond of the substrate. A nonlinear Hammett plot was obtained to examine substituted arenes where a strong electronic dependence (ρ = 1.67) was observed for electron-donating groups, whereas no electronic dependence was observed for electron-withdrawing groups. Electron-donating substituents in the para position were shown to have a bigger impact on the C–H bond cleavage step, whereas electron-withdrawing substituents influenced the substrate-binding step. Although cleavage of the C–H bond was predicted to be more facile with arenes that contain substituents in the para position by DFT calculations, the cyclometalations of anisole and benzonitrile were observed experimentally. This ...}, number={15}, journal={ORGANOMETALLICS}, publisher={American Chemical Society (ACS)}, author={Frasco, Daniel A. and Mukherjee, Sriparna and Sommer, Roger D. and Perry, Cody M. and Lambic, Nikola S. and Abboud, Khalil A. and Jakubikoya, Elena and Ison, Elon A.}, year={2016}, month={Aug}, pages={2435–2445} }
 @article{frasco_sommer_ison_2015, title={ortho-C–H Activation of Thiobenzoic Acid: Synthesis, Characterization, and Reactivity of Iridium Thiobenzoate Complexes}, volume={34}, ISSN={["1520-6041"]}, DOI={10.1021/om501115u}, abstractNote={Cp*Ir(Me2SO)(OAc)2, 1, has been shown to activate an ortho-C–H-bond of thiobenzoic acid in methanol at 100 °C to form the novel iridium complex (Cp*Ir(S(O)CC6H4))2, 5. Unlike the similar reaction with benzoic acid, this new iridium complex exists as a dimer with bridging sulfur ligands. To our knowledge, this is the first example of metal facilitated C–H activation of thiobenzoic acid. Complex 5 reacted with CO to form Cp*Ir(CO)(S(O)CC6H4), 6. Complex 5 was also shown to react with the electrophilic methyl reagents methyl iodide and methyl triflate. The reaction with methyl iodide resulted in the formation of Cp*Ir(I)(SMe(O)CC6H4), 7, while the reaction with methyl triflate resulted in the bimetallic complex [(Cp*Ir(SMe(O)CC6H4)(Cp*Ir(S(O)CC6H4)][OTf], 8. The order of reactivity with electrophilic methyl reagents was MeOTf > MeI >MeOAc, which reflects the nucleophilic character of the sulfoxyl group of the cyclometalated thiobenzoate ligand. Attempts at cyclization with complex 5 and olefins and alkynes w...}, number={1}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Frasco, D.A. and Sommer, R.D. and Ison, E.A.}, year={2015}, pages={275–279} }
 @article{frasco_lilly_boyle_ison_2013, title={Cp*Ir-III-Catalyzed Oxidative Coupling of Benzoic Acids with Alkynes}, volume={3}, ISSN={["2155-5435"]}, DOI={10.1021/cs400656q}, abstractNote={Cp*Ir(III) complexes have been shown to catalyze the oxidative coupling of benzoic acids with alkynes in methanol at 60 °C to form a variety of isocoumarins. The use of AgOAc as an oxidant was required to facilitate significant product formation. Alkyl alkynes were shown to be more reactive substrates than aryl alkynes, and a number of functional groups were tolerated on benzoic acid. Combined mechanistic and computational studies (BP86) revealed that (1) C–H activation occurs via an acetate-assisted mechanism; (2) C–H activation is not turnover limiting; and (3) the oxidant oxidizes the reduced form of the catalyst via an Ir(I)–Ir(II)–Ir(III) sequence.}, number={10}, journal={ACS CATALYSIS}, author={Frasco, Daniel A. and Lilly, Cassandra P. and Boyle, Paul D. and Ison, Elon A.}, year={2013}, month={Oct}, pages={2421–2429} }