Stereoselective synthesis of tetrasubstituted alkenes and copper-catalyzed interrupted cross-coupling reactions

Chapter 1 Stereoselective Synthesis of All-Carbon Tetrasubstituted Alkenes from In Situ Generated Ketenes and Organometallic Reagents. Efficient and stereoselective formation of tetrasubstituted alkenes with four different carbon-linked groups is a significant yet challenging problem in chemical synthesis. A new and direct method to access stereodefined tetrasubstituted alkenes has been developed. This two-step strategy involves in situ generation of a ketene, stereoselective formation of an alkenyl pseudohalide, and a subsequent stereospecific metal-catalyzed cross-coupling reaction.;Chapter 2 Cu-Catalyzed Suzuki-Miyaura-Type Cross-Coupling Reactions. Suzuki-Miyaura cross-coupling reactions have proven to be an indispensable method for chemical synthesis. Significant advances have been achieved to couple a wide-range of cross partners under mild conditions. Typically these reactions are catalyzed by Pd- and Ni-complexes. Herein, a Cu-catalyzed Suzuki-Miyaura-type cross-coupling reaction is presented. The method provides access to orthogonal reactivity compared to more traditional Pd-catalyzed processes; furthermore, the mechanism of the Cu-catalyzed Suzuki-Miyaura-type cross-coupling is studied both experimentally and computationally in detail.;Chapter 3 Cu-Catalyzed Alkyne- and Alkene-Interrupted Cross-Coupling Reactions. The importance of Cu-catalyzed cross-coupling can be further expanded to alkyne or alkene-interrupted cross-coupling reactions. Through this one-step strategy, simple alkenes and alkynes can be easily functionalized with two different groups to rapidly establish complex molecules. Herein, two related Cu-catalyzed interrupted cross-coupling reactions are investigated in detail. The first is a carboboration of alkynes and allenes, which can be categorized as Cu-catalyzed interrupted Miyaura-type borylation reaction. The second one is an enantioselective diarylation of alkenes, which is Cu-catalyzed alkene-interrupted Suzuki-Miyaura-type cross-coupling.