DescriptionThe selective dehydrogenation of alkane and alkyl groups has a great impact on the synthesis of fuels and both commodity and fine chemicals. In this thesis, the work described is aimed at developing and understanding alkane functionalization using high-oxidation state Ir complexes. Simple Lewis acid such as Na+, Li+ or BAr3 were discovered to catalyze two of the most relevant and fundamental organometallic reactions with an Ir(III) species, (Phebox)Ir(OAc)(H) (Phebox = 2,6-bis(4,4-dimethyloxazolinyl)-3,5-dimethylphenyl): olefin insertion and C‒H addition (and their respective microscopic reverse reactions). The results of DFT calculations indicate that the Lewis acid primarily promotes the opening of a vacant coordination site via interaction with acetate ligand. An acceptorless n-alkane dehydrogenation system was developed co-catalyzed by (Phebox)Ir(OAc)(H) and NaBArF4. Attempts to catalyze transfer dehydrogenation with (Phebox)Ir(OAc)(H)/Na+ afforded unexpected results. Alkane solutions of (Phebox)Ir(OAc)(H)/Na+ with 1-alkene added as hydrogen acceptor, in contrast with PCP-type catalysts, selectively effected transfer dehydrogenation of the olefins, olefin disproportionation to give mostly dienes. When ethylene was added as a hydrogen acceptor, we obtained high yields of dienes and polyenes, derived from ethylene oligomerization and dehydrogenation. These results indicate that Na+ catalyzed both insertion of olefins into the Ir-alkyl bond of (Phebox)Ir(OAc)(Alkyl), as well as C‒H activation by the same species. (Phebox)Ir(OAc)(H)/Na+ system was also discovered to catalyze the norbornene isomerization to form nortricyclane. An Ir(I) complex, (Phebox)Ir(η2-C2H4)2, was synthesized and discovered to catalyze the ethylene dehydrogenative coupling reaction via an iridacyclopentane intermediate. DFT calculation suggest that the iridacyclopentane intermediate undergoes a very unusual β-hydride elimination to give 1,3-butadiene.