Asymmetric C-H Functionalization Reaction Catalyzed By Chiral Bronsted Acid And Transition Metal

Direct functionalization of C-H bonds has been a research topic that has been receiving increasing interest in organic chemistry because it provides a strategically new opportunity for the creation of structurally complex and diverse organic molecules. In this dissertation, we have developed several sp3and sp2C-H functionalization reactions catalyzed by Br(?)nsted acid and transition metal and furnished a serious of nitrogen-containing heterocyclic compounds.We have disclosed that chiral phosphoric acid could fulfill sp3C-H adjacent to nitrogen functionlization well. The reaction proceeds initially with the condensation of o-aminobenzoketone with aniline in the presence of a chiral Br(?)nsted acid to generate an iminium species, which is presumably able to undergo an asymmetric1,5-hydride shift process and a subsequent ring closing reaction to give a cyclic aminal. Bisphosphoric acid showed much better stereoselectivity than other PA and gave cyclic aminals in fairly good diastereo-and enantioselectivities.We have successfully applied muti-catalysts system with metal catalysts and organocatalysts to C-H functionalization reactions which could not complete well using single catalyst previous. This was also in accordance with the concept of "atom economic" in green chemistrywe have developed a relay catalytic hydroamination/redox reaction, which is able to directly assemble the tertiary amine-substituted3-en-1-ynes derivatives and various amines into cyclic aminals in excellent yields (up to99%) and moderate to high diastereoselectivities (up to95/5dr) by using gold(I) complex and trifluoromethanesulfonic acid as the combined catalyst. This method provides an alternative strategy to make the unactivated alkynes undergo the1,5-hydride transfer redox reaction. The enantioselective variant of this process has been realized by using excess amounts of chiral BINOL-derived phosphoric acid capable of delivering the corresponding products with up to99%ee. we have demonstrated that the combined use of a palladium(II) complex of chiral Bu-QUOX ligand and a chiral phosphoric acid enabled a highly enantioselective oxi-dative cascade cyclization reaction of N-(2,2-disubstituted hex-5-en-1-yl)acrylamides, providing a straightforward method to access chiral6,5-bicyclic nitrogeneous hetero-cycles in moderate to good yields and with excellent enantioselectivities. A synergistic effect between the palladium(II) complex and the chiral phosphoric acid was found in the catalysis. The chiral ligand and anion cooperatively control the stereoselectivity.