Catalytic H/D exchange reactions of benzene and benzoic acid with deuterated solvents have been studied using (Cp*IrCl2)2. A 1:1 mixture of D2O/CD3OD produced the highest turnover numbers for benzene. High levels of deuterium incorporation into benzoic acid were observed only when sodium acetate was added to the reaction mixture. Attempts at producing hydroxybenzoic acid by catalytic C–H functionalization of benzoic acid with benzoquinone were unsuccessful. Instead, 2-hydroxy-6H-benzo[c]chromen-6-one was isolated as the major product. An array of substituted benzoic acids was analyzed for this functionalization reaction. Preliminary mechanistic studies indicate that the benzochromenones are formed by C–H bond activation of benzoic acid followed by insertion of benzoquinone into the iridium–carbon bond.

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Generation of a reactive Tp′PtMe fragment (Tp′ = hydridotris(3,5-dimethylpyrazolyl)borate) in the presence of free isonitrile leads to a σ-isocyanide Pt(II) complex. Related Pt(II) aminocarbene complexes can be synthesized by nucleophilic attack at the isonitrile carbon followed by addition of acid. Protonation at nitrogen produces the observed aminocarbene product. Nucleophilic attack at the carbon of the coordinated isonitrile by metal alkyl reagents followed by addition of iodomethane as an electrophilic reagent results in Pt(IV) iminoacyl complexes of the type Tp′Pt(RCN(2,6-C6Me2H3))Me2, where R = Me, Et. Alternatively, the Pt(II) aminocarbene complexes can be converted to these same Pt(IV) iminoacyl products by deprotonation of the N−H site followed by addition of iodomethane, with the outcome reflecting methylation at platinum. Addition of acid to the Pt(IV) iminoacyl complex generates a rare cationic Pt(IV) aminocarbene complex via protonation at the iminoacyl nitrogen as {Tp′Pt(C(R)NH(2,6-C6Me2H3))Me2}{BF4} forms.