Synthesis Of Nitrogen Heterocycles Via Pd-catalyzed Intermolecular C-H Of Heteroaromatic Compound Addition To Nitriles

Recently,transition-metal-catalyzed C-H bond additions to nitriles have experienced remarkable advances.In most cases,nitriles can serve as C building blocks and provide acyclic aryl ketone products,which don’t meet the basic principles of atomic economy.Nitrogen-containing heterocyclic compounds which are widely found in natural products,pharmaceuticals and organic materials,are important organic synthetic intermediates.Therefore,it is important to develop this strategy which is applicable to the assembly of azaheterocyclic skeletons in an atom-economic fashion,in which nitriles serve as C-N building blocks.This thesis mainly includes the following aspects:(1)We have developed a practical and flexible intermolecular protocol for the diverse synthesis of trisubstituted oxazole derivatives via a Pd-catalyzed C-H addition of various electronic-rich heteroarenes to nitriles/cyclization sequences.Under the optimal conditions,various trisubstituted oxazoles can be prepared from readily available starting materials in good to high yields with high tunability.Meanwhile,these products have obvious inhibitory effect on tumor cells,which are Hep G2 and SMMC-7721.(2)We have developed a new protocol for the diverse synthesis of functionalized β-carbolines and γ-carbolines via Pd-catalyzed C-H addition of indoles to nitriles/cyclization sequences.Under the optimal conditions,a diverse range of functionalized β-carbolines and γ-carbolines can be prepared from readily available starting materials in good to high yields.The catalytic system tolerates a broad substrate scope.