Highly regioselective organo photocatalysis of 4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene) for the arylation of 2H-indazole is demonstrated.
Ligand-Promoted <i>Meta</i>-C–H Arylation of Anilines, Phenols, and Heterocycles
作者:Peng Wang、Marcus E. Farmer、Xing Huo、Pankaj Jain、Peng-Xiang Shen、Mette Ishoey、James E. Bradner、Steven R. Wisniewski、Martin D. Eastgate、Jin-Quan Yu
DOI:10.1021/jacs.6b04966
日期:2016.7.27
Here we report the development of a versatile 3-acetylamino-2-hydroxypyridine class of ligands that promote meta-C-H arylation of anilines, heterocyclic aromatic amines, phenols, and 2-benzyl heterocycles using norbornene as a transient mediator. More than 120 examples are presented, demonstrating this ligand scaffold enables a wide substrate and coupling partner scope. Meta-C-H arylation with heterocyclic
A Biphilic Phosphetane Catalyzes N–N Bond-Forming Cadogan Heterocyclization via P<sup>III</sup>/P<sup>V</sup>═O Redox Cycling
作者:Trevor V. Nykaza、Tyler S. Harrison、Avipsa Ghosh、Rachel A. Putnik、Alexander T. Radosevich
DOI:10.1021/jacs.7b03260
日期:2017.5.24
chemoselective catalytic synthesis of 2H-indazoles, 2H-benzotriazoles, and related fused heterocyclic systems with good functional group compatibility. On the basis of both stoichiometric and catalytic mechanistic experiments, the reaction is proposed to proceed via catalytic PIII/PV═O cycling, where DFT modeling suggests a turnover-limiting (3+1) cheletropic addition between the phosphetane catalyst and nitroarene
Rhodium(<scp>iii</scp>)-catalyzed regioselective distal <i>ortho</i> C–H alkenylation of <i>N</i>-benzyl/furanylmethylpyrazoles directed by <i>N</i>-coordinating heterocycles
作者:Hyewon Kim、Raju S. Thombal、Hari Datta Khanal、Yong Rok Lee
DOI:10.1039/c9cc06758b
日期:——
C–H activation of challenging N-benzylpyrazoles was accomplished by employing rhodium(III) catalysis. This C–H activation reaction proceeds via a six-membered rhodacycle intermediate and enables distal regioselective alkenyl-functionalization on the aromaticring of N-benzylpyrazoles without the formation of bis-adducts. High functional group tolerance, low catalyst loading, and superior reactivity
具有挑战性的N-苄基吡唑类化合物的C–H活化是通过铑(III)催化完成的。这种C–H活化反应是通过六元的Rhodacycle中间体进行的,可在N-苄基吡唑的芳香环上进行远端区域选择性烯基官能化,而不会形成双加合物。该方案的一些吸引人的特征是高官能团耐受性,低催化剂负载量和烯烃部分对N-苄基吡唑的优异反应性。该方案为吲唑,苯并[ d ] [1,2,3]三唑和1-(呋喃-3-基甲基)-1 H的区域选择性官能化提供了广阔的范围。-吡唑产率高。
A general and efficient approach to 2H-indazoles and 1H-pyrazoles through copper-catalyzed intramolecular N–N bond formation under mild conditions
作者:Jiantao Hu、Yongfeng Cheng、Yiqing Yang、Yu Rao
DOI:10.1039/c1cc13908h
日期:——
A new efficient copper-catalyzed intramolecular amination reaction has been developed to readily synthesise a wide variety of multi-substituted 2H-indazole and 1H-pyrazole derivatives from easily accessible starting materials under mild conditions. A highly selective ligand for estrogen receptor β was prepared in three steps by employing this method.