A Pd-catalyzed, boron ester-mediated, reductive cross-coupling of two aryl halides to synthesize tricyclic biaryls
作者:Zhilong Chen、Xiaodong Wang
DOI:10.1039/c7ob01237c
日期:——
Tricyclic biaryls are important scaffold structures in many natural products and lead compounds in drug discovery. The formation of a biaryl unit is often the key step for the synthesis of tricyclic biaryls. Despite significant progress toward the synthesis of biaryl compounds in recent years, the direct cross-coupling of two different aryl halides is still challenging and robust methods are lacking
A palladium-catalyzed multicomponentreaction (MCR) involving aryne, CO, and aniline is established for straightforward assembly of a phenanthridinone scaffold through C–H bond activation. Free combination with multiple kinds of readily available anilines and arynes is facilely achieved for phenanthridinone construction without prefunctionalization. Representative natural products were subsequently
Dilithium Tetrachlorocuprate(II) Catalyzed Oxidative Homocoupling of Functionalized Grignard Reagents
作者:Jiangmeng Ren、Bu-Bing Zeng、Si-Kai Hua、Qiu-Peng Hu
DOI:10.1055/s-0032-1316841
日期:——
to excellent yields. An efficient procedure is described for the oxidative homocoupling of functionalized Grignardreagents using a catalytic amount of dilithium tetrachlorocuprate(II) (CuLi2Cl4) in the presence of pure oxygen gas. This method is applied successfully to a variety of aryl, heteroaryl, alkyl, alkenyl and alkynyl halides, which are converted into the corresponding homocoupled products in
palladium‐catalyzed regiodivergent C1 insertion multicomponent reaction involving aryne, CO, and 2‐iodoaniline is established to construct the scaffolds of phenanthridinone and acridonealkaloids. Regioselective control is achieved under the guidance of selective ligands. The phenanthridinones are solely obtained under ligand‐free condition. In comparison, application of the electron‐abundant bidentate ligand dppm
This study investigated the effect of oxygen substituents in the benzoyl part of N-(2-iodophenyl)benzamide on the coupling position in its Pd-assisted biaryl couplingreaction. Benzamide with methylenedioxy and acyloxy groups yielded the ortho-product formed predominantly by connection to a more hindered carbon. The mechanism is discussed from the perspectives of both steric and coordinated effects