Copper-catalyzed selective difunctionalization of N-heteroarenes through a halogen atom transfer radical process
作者:Hui-Lin Fang、Qiu Sun、Rong Ye、Jing Sun、Ying Han、Chao-Guo Yan
DOI:10.1039/c9nj03471d
日期:——
A highly regioselective Cu-catalyzed difunctionalization of different N-heteroarene salts such as quinolinium and benzothiazolim salts was developed with ether and X− (X = Br, Cl) as the halogen source under mild conditions. This transformation involved the combination of oxidative coupling, selective free radical resonance and a copper-catalyzed halogen atom-transfer radical process. The regiochemistry
Regio- and Diastereoselective Three-Component Reactions via Trapping of Ammonium Ylides with <i>N</i>-Alkylquinolinium Salts: Synthesis of Multisubstituted Tetra- and Dihydroquinoline Derivatives
作者:Zhenghui Kang、Dan Zhang、Wenhao Hu
DOI:10.1021/acs.orglett.7b01664
日期:2017.7.21
Pd(II)-catalyzed three-component reactions via trapping of ammonium ylides with N-alkylquinolinium salts are reported. These reactions provided polyfunctional polycyclic tetrahydroquinolines or 4-substituted 1,4-dihydroquinolines in excellent yields (89–99% and 89–98%, respectively) with high regioselectivities and moderate to good diastereoselectivities (up to 95:5 dr) under mild reaction conditions
Regio- and diastereoselective dearomatizations of <i>N</i>-alkyl activated azaarenes: the maximization of the reactive sites
作者:Hong-Jie Miao、Le-Le Wang、Hua-Bin Han、Yong-De Zhao、Qi-Lin Wang、Zhan-Wei Bu
DOI:10.1039/c9sc04880d
日期:——
An unprecedented base-promoted multi-component one-pot dearomatization of N-alkyl activated azaarenes was developed, which enabled the synthesis of complex and diverse bridged cyclic polycycles with multiple stereocenters in a highly regio- and diastereoselective manner. Besides, we realized the step-controlled dearomative bi- and trifunctionalization of quinolinium salts. These transformations not
reactive N-heteroaromatics to useful frameworks. Here, by a strategy merging hydrogen transfer and selective coupling, we present a ruthenium-catalyzed deconstruction of N-heteroaromatics to functionalized arylamines with 2-aminoaryl methanols. The reaction is achieved via sequential functionalization of the β and α sites of the initially formed N-heteroarenium salts followed by a C–N cleavage, which proceeds
Herein, we report a catalytic reductive three-component annulation reaction for the construction of fused heterocycles featuring a pyrano[2,3-b]pyridyl motif from N-heteroarenium salts and formaldehyde with cyclic 1,3-diketones or 4-hydroxycoumarins.