Palladium Norbornene Cooperative Catalysis

摘要

Chapter 1 introduce the historical background and discovery of Palladium/Norbornene cooperative catalysis. Catellani and coworkers did systematic organometallic study and catalytic system study to prove the concept and mechanism of palladium/norbornene cooperative catalysis. Detailed organometallic study and correct mechanism proposal provide were discussed. Electrophile constraint, aryl iodide constraint, ortho constraint are three major limitations for the Palladium/Norbornene cooperative catalysis.;Chapter 2 describe a palladium/norbornene-catalyzed ortho-arene amination to introduce amine at ortho position of aryl iodide and hydrogen atom at the ipso position. O-benzoyloxyamines and iso-propanol are employed as the amine source (oxidant) and reductant respectively. This transformation gives complementary site-selectivity at the ortho instead of the ipso -position of aryl halides with high functional group tolerance.;Chapter 3 describe a palladium/norbornene-catalyzed ortho-arene acylation of aryl iodides via Catellani-type C--H functionalization. This transformation is enabled by isopropyl carbonate anhydrides as a dual functional reagent serving as both an acyl cation equivalent and a hydride source.;Chapter 4 describe the development of general approaches for aryl bromide-mediated Pd/NBE cooperative catalysis. Ortho amination, acylation and alkylation of aryl bromides have all been realized in good efficiency. Importantly, various heteroarene substrates also work well and a wide range of functional groups are tolerated. Sequential cross coupling/ortho functionalization reactions and consecutive palladium/norbornene-catalyzed difunctionalization to construct penta-substituted aromatics and two-step meta-functionalization reactions are achieved.;Chapter 5 describe a highly meta-selective C?H arylation using simple tertiary amines as the directing group. This method takes advantages of Pd/norbornene catalysis offering a distinct strategy to control the site-selectivity. The reaction was promoted by commercially available AsPh3 ligand and unique "acetate cocktail". Aryl iodides with an ortho-electron withdrawing group were employed as the coupling partner. A wide range of functional groups, including some heteroarenes, can be tolerated under the reaction conditions. The amine directing group can be easily installed and trans-formed to other common versatile functional groups.