Rhodium-catalyzed Controllable C2 C-H Alkenylation And Alkylation Of N-quinoline Indoles

Transition-metal-catalyzed direct C-H bond functionalization has proven to be an effective strategy for the rapid construction of various C-C bonds.In this regard,olefins are often used as coupling partners due to their extensive reactivity in metal catalysis to achieve direct C-C bond coupling.The thesis developed a scheme for the functionalization of alkenes and the C-H bond at 2-position of indole catalyzed by rhodium,which provides a convenient and efficient method for the synthesis of functionalized alkenylated and alkylated derivatives.The reaction features broad substrate scope and good tolerance of functional groups,and the corresponding products could be transformed to structurally diverse indole derivatives,especially modification of complex natural products and synthesis of a novel kind of indole-based N,P ligand.The details are as follows:1.The catalytic C2 C-H alkenylation of N-quinoline indoles was explored by Rh(III)catalysis.which could be accomplished smoothly by utilizing a variety of alkenes to generate a series of alkenylated indoles.Notably,several bioactive scaffolds are also compatible with this catalytic system and a novel kind of bifunctional ligand can be synthesized.This reaction conducted under mild reaction conditions,thus providing an practical and environment-friendly alternative for the catalytic C-H functionalization of indoles.2.Rh(III)-catalyzed C2 C-H alkylation of N-quinoline indoles was developed.The reaction employed enones as the alkylated reagents to access various indole-substituted ketones.Generally,the tolerance of diverse substrates enabled a straightforward method for the synthesis of functionalized ketones.In addition,with the similar reaction conditions,the deuterated indoles could be obtained with good regioselectivity and high deuteration.3.A facile synthesis of isocoumarin and ?-pyrones derivatives by Ru(II)-catalyzed oxidative annulation of aromatic acids and alkynes were reported.The reaction could undergo smoothly in water by use of air as the sole oxidant and accomplishes with the tolerance of a wide range of functional groups.Additionally,the oxidative cyclization of benzoic acid and acrylate is also achieved in the same conditions to furnish the isobenzofuran-1(3H)-one scaffold.