Rh(?)-/Ir(?)-catalyzed C-H Activation Of Arenes In Coupling With Unsaturated Molecules And Nucleophilies

As an efficient and atom-economic route in organic synthesis, transition-metal-catalyzed C-H activation has been attracted more and more chemists' attentions. In recent years, Rh(?) and Ir(?) catalysts have been increasingly employed in C-H activation due to their high activity, high selectivity, broad scopes and functional-groups. This dissertation mainly focused on Rh(?)-catalyzed coupling of arenes with strained rings by C-H activation, C-H nitration, C-H alkynylation, annulation with alkynes for construction of various cyclic compounds, coupling with quinones, and Ir(?)-catalyzed C-H alkynylation of arenes. The results are as following:1. A reaction system was developed combining ring-opening reaction of strainen ring and C-H activation of arenes. Under redox-neutral conditions,2-naphthylation products were prepared from 7-oxabenzonorbornadienes and arenes by C-H activation and dihydrative processes using [RhCp*Cl2]2 as catalyst, AgSbF6 and PivOH as additives in dioxane at 130?. In contrast, using AgOAcas oxidant in dioxane at 120?, the coupling of these arenes with 7-azabenzonorbornadienes occurred to furnish dihydrocarbazoles through double C-H activation and intramolecular C-N formation. And mechanism was also explored, where a seven-membered rhodacyclic complex was isolated as a key intermediate.2. Using the umpolung strategy, an approach of Rh(?)-catalyzed C-H activation of arenes coupling with nucleophilies was discovered. PhI(OTs)OH was added to the reaction system, which made the electrical properties matching between arenes and nucleophilies, in order to realize Rh(?)-catalyzed C-H direct nitration using NaNO2 as a nucleophilie. And C-H alkynylation of arenes was realized using TIPS-EBX as umpolung alkynylation reagent. It is found that Rh(?) and Ir(?) exhibited complementary substrate scope in C-H alkynylation.3. A series of cyclics with potential utility were synthesized by Rh(?)-catalyzed C-H activation of arenes bearing various directing groups and annulation with alkynes under redox-neutral or oxidative conditions.a) Under redox-neutral conditions, Rh(?)-catalyzed C-H annulation of N-fert-butyl-?-arylnitrones with alkynes was realized for the synthesis of indenones directing by nitrone group. The reaction mechanism was also explored.18O-labeled experiment indicated that the oxygen atom inindenones could originate from water.b) And a 100% atom-economic Rh(?)-catalyzed synthesis of isoquinoline derivatives with a proximal secondary alcohol was developed involving intramolecular N-O cleavage as internal oxidant.c) Rh(?)-catalyzed synthesis of sultones via the oxidative coupling of sulfonic acids with alkynes was described. Different types of products were obtained by controlling the reaction conditions. Sultones were obtained using AgOAc as oxidant and dioxane as solvent. Multi substituted naphthalene was produced oxidized by AgOAc and Ag2CO3 in t-BuOH.d) Rh(?)-catalyzed C-H activation of 2-phenylimidazo[1,2-a]pyridines coupling with alkynes was achieved. Selective mono versus twofold C-H activation were attained under condition control, leading to fused ring compounds or isoquinolinium salts. Fused ring compounds formed via double C-H activation using AgOAc as oxidant. isoquinolinium salts was prepared using Cu(OAc)2 as oxidant in presence of AgBF4.4. Rh(?)-catalyzed synthesis of arylquinones by C-H activation of N-(alkyl)benzamides coupling with various quinones was realized using Ag2CO3 as an oxidant. And under redox-neutral conditions,2-hydroxy-6H-benzo[c]chromen-6-ones were obtained via a cascade of cross-coupling followed by lactonization.