Theoretical Investigation On The Transition Metal Complex Selective Catalyzed C-H Activation

More and more researchers have focused attention on the organic reactions catalyzed by transition metal complex. Transition metal catalysts?Ni, Ru, Rh, Pd, Ir and Pt? significantly improve the reaction activity and selectivity, in which far better than nonmetal catalysts or small organic molecules catalysts. Computational chemistry is increasingly used to study and to predict organometallic reaction mechanisms, due to the significant development in computing method, computing power, and software development. Theoretical investigation on the transition metal complex selective catalyzed C-H activation will be study by quantum chemical calculation. The reaction mechanism of C-H activation,the role of metal center and ligand, the rules and nature of modification of metal center, the critical feature of selectivity C-H activation, will be systematically research. The following contents are included:?1? A density functional theory ?DFT? study was performed to reveal that the substituent effects in the ?-site have an effect on the chemoselectivity of the intramolecular Buchner reaction of diazoacetamide catalyzed by Rh₂?OAc?₄. The substituent effect is investigated considering five different groups ?Z =-Me, -OMe, -H, -CN and -C?O?Me? in the substrates. The C-H insertion/C-C aromatic addition reaction of diazoacetamide catalyzed by Cu?acac?₂ and CuBr.?2? A density functional theory ?DFT? study has been conducted to unveil the mechanisms of tandem oxidative acetoxylation/ortho C-H activation/carbocyclization catalyzed by Pd?OAc?₂. The potential competitive reaction Pathways between oxidative acetoxylation and ortho C-H activation, C-H activation with outer-sphere and inner-sphere acetate ligands, and the role of DMSO in the reaction have been discussed in detail.Moreover, the oxidizing agent of BQ and O₂ play an important role in Pd?0?/Pd??? redox reaction.?3? Using DFT to study the C-H activation catalyzed by Pd???, which is the rate determining step in the tandem reaction contains C-H activation,C-C coupling, and Tsuji-Trost reaction. The theoretical calculation suggested the sequences of the tandem reaction, and the transition state catalyzed by Pd assisting with OAc coordination.