Cobalt(III)‐Catalyzed, DMSO‐Involved, and TFA‐Controlled Regioselective C−H Functionalization of Anilines with Alkynes for Specific Assembly of 3‐Arylquinolines
作者:Peiquan Zhang、Yurong Yang、Zhiyong Chen、Zhang Xu、Xuefeng Xu、Zhi Zhou、Xiyong Yu、Wei Yi
DOI:10.1002/adsc.201801709
日期:2019.6.18
Herein, a novel cobalt(III)‐catalyzed and TFA‐controlled [3+2+1] cyclization of diverse anilines and terminal alkynes has been realized by using DMSO as both the solvent and the C1 source, which led to the specific synthesis of privileged 3‐arylquinolines in one pot and regioselectively. Mechanistic investigations revealed that this versatile transformation might be initiated with a C−H activation
Direct <i>ortho</i>-Arylation of Pyridinecarboxylic Acids: Overcoming the Deactivating Effect of sp<sup>2</sup>-Nitrogen
作者:Adam J. S. Johnston、Kenneth B. Ling、David Sale、Nathalie Lebrasseur、Igor Larrosa
DOI:10.1021/acs.orglett.6b03085
日期:2016.12.2
Direct arylations of pyridines are challenging transformations due to the high Lewis basicity of the sp2-nitrogen. The use of carboxylates as directinggroups is reported, facilitating the Pd-catalyzed C–H arylation of this difficult class of substrates. This methodology allows regioselective C3/C4 arylation, without the need to use solvent quantities of the pyridine, and using low-cost chloro- and
Suzuki-Miyaura Cross-Coupling Reactions in Flow: Multistep Synthesis Enabled by a Microfluidic Extraction
作者:Timothy Noël、Simon Kuhn、Andrew J. Musacchio、Klavs F. Jensen、Stephen L. Buchwald
DOI:10.1002/anie.201101480
日期:2011.6.20
Continuous success: A continuous‐flowSuzuki–Miyaura cross‐coupling reaction starting from phenols was made possible through use of an efficient microfluidicextraction operation and a packed‐bed reactor. Various biaryls were obtained in excellent yield (14 examples). TBAB=Bu4N+Br−.
A new approach for the regioselective functionalization of the C-3-position of quinolines is described. The method utilizes heteroatom guided regioselective C-3 palladation followed by arylation via transmetalation with aryl boronic acids to yield 3-aryl-N-acyl-1,2-dihydroquinolines. In a one-pot sequence, N-deacylation followed by aromatization leads to important 3-arylquinolines in good yields.
Enantioselective Reduction of 3-Substituted Quinolines with a Cyclopentadiene-Based Chiral Brønsted Acid
作者:Weijun Tang、Xiaofang Zhao、Jianliang Xiao
DOI:10.1055/s-0036-1589012
日期:2017.7
Abstract Enantioselective reduction of 3-substituted quinolines has been achieved using a cyclopentadiene-based chiralBrønstedacid as catalyst and Hantzsch ester as hydrogen donor, affording the corresponding tetrahydroquinolines in good enantioselectivities. Enantioselective reduction of 3-substituted quinolines has been achieved using a cyclopentadiene-based chiralBrønstedacid as catalyst and