A Practical, Metal-Free Synthesis of 1<i>H</i>-Indazoles
作者:Carla M. Counceller、Chad C. Eichman、Brenda C. Wray、James P. Stambuli
DOI:10.1021/ol800053f
日期:2008.3.1
The synthesis of 1H-indazoles is achieved from o-aminobenzoximes by the selective activation of the oxime in the presence of the amino group. The reaction occurs with a variety of substituted o-aminobenzoximes using a slight excess of methanesulfonyl chloride and triethylamine at 0-23 degrees C and is amenable to scale-up. The synthesis of 1H-indazoles under these conditions is extremely mild compared
Ruthenium-Catalyzed Direct CH Amidation of Arenes Including Weakly Coordinating Aromatic Ketones
作者:Jiyu Kim、Jinwoo Kim、Sukbok Chang
DOI:10.1002/chem.201301025
日期:2013.6.3
CH activation: The ruthenium‐catalyzed direct sp2 CHamidation of arenes by using sulfonyl azides as the amino source is presented (see scheme). A wide range of substrates were readily amidated including arenes bearing weakly coordinating groups. Synthetic utility of the thus obtained products was demonstrated in the preparation of biologically active heterocycles.
Chemoselective synthesis of ortho ethynylhydrazones 7 derived from 2-iodoacetophenone via a Sonogashira coupling is reported for the first time.
从2-碘苯乙酮经Sonogashira偶联合成的源自2-乙炔基肼酮7的化学选择性合成首次报道。
Direct N-Alkylation and Kemp Elimination Reactions of 1-Sulfonyl-1<i>H</i>
-Indazoles
作者:Meng Tang、Bingjie Chu、Xiaowei Chang
DOI:10.1002/asia.201800741
日期:2018.8.16
The reactions of 1‐sulfonyl‐1H‐indazoles under basic conditions are discussed, and the direct N‐alkylation and Kemp elimination reactions of these compounds are reported. A series of 2‐(p‐tosylamino)benzonitriles and N‐alkyl indazoles were prepared in good yields. Moreover, the 2‐(p‐tosylamino)benzonitriles could be transformed into a diverse range of important derivatives in a one‐pot reaction. This
Copper(I) Oxide-Mediated Cyclization of<i>o</i>-Haloaryl<i>N</i>-Tosylhydrazones: Efficient Synthesis of Indazoles
作者:Meng Tang、Yuanfang Kong、Bingjie Chu、Dan Feng
DOI:10.1002/adsc.201500953
日期:2016.3.17
An efficientsynthesis of indazoles from readily accessible E/Z mixtures of o‐haloaryl N‐tosylhydrazones has been developed. The thermo‐induced isomerization of N‐tosylhydrazones is discussed. A series of valuable indazole derivatives are prepared in good yields, and the method has been successfully applied to the synthesis of the bioactive compounds, lonidamine, AF‐2785, axitinib, YC‐1 and YD‐3.