138306-37-3Relevant academic research and scientific papers
A novel and efficient synthesis of 2-aryl-2H-indazoles via SnCl 2-mediated cyclization of 2-nitrobenzylamines
Shi, Da-Qing,Dou, Guo-Lan,Ni, Sai-Nan,Shi, Jing-Wen,Li, Xiao-Yue,Wang, Xiang-Shan,Wu, Hui,Ji, Shun-Jun
, p. 2509 - 2512 (2007)
A mild, efficient, and novel synthesis of 2-aryl-2H-indazoles via cyclization of 2-nitrobenzylamines promoted by SnCl2·2H 2O has been described. This method applies to a wide scope of substrates containing electron-donating and elect
Metal-free regioselective C-H amination for the synthesis of pyrazole-containing 2H-indazoles
Wang, Kai,Wei, Tingting,Zhang, Yujia,Hou, Jiahao,Bai, Renren,Xie, Yuanyuan
, p. 1787 - 1794 (2021/03/14)
A general and practical regioselective approach for the C-H amination of 2H-indazoles under transition-metal-free conditions was developed. A series of substrates were tested showing eminent functional group tolerance and affording the C-N functionalization products in good to excellent yields. Mechanism studies revealed that a radical process was involved in this transformation.
Manganese-Catalyzed Electrochemical Tandem Azidation-Coarctate Reaction: Easy Access to 2-Azo-benzonitriles
Maiti, Debabrata,Mahanty, Kingshuk,De Sarkar, Suman
, p. 1742 - 1747 (2021/04/05)
A one-pot cascade transformation consisting of an electrochemically driven azidation of 2H-indazole followed by coarctate fragmentation is developed to synthesize the 2-azo-benzonitrile motif. This manganese-catalyzed transformation is external-chemical-oxidant-free and operates at ambient temperature under air. This methodology exhibits good functional group tolerance, affording a broad range of substrate scopes of up to 89% isolated yield. Diverse derivatization of the 2-azo-benzonitrile product resulted in other valuable scaffolds.
Synthesis, antiprotozoal activity, and cheminformatic analysis of 2-phenyl-2h-indazole derivatives
Aguilera-Perdomo, Jacobo David,Cortés-Benítez, Francisco,Cortés-Gines, Miguel,Del Angel, Kevin Samael Olascoaga,Pérez-Villanueva, Jaime,Palacios-Espinosa, Juan Francisco,Quintana-Salazar, Edgar A.,Rodríguez-Villar, Karen,Soria-Arteche, Olivia,Yépez-Mulia, Lilián
, (2021/05/28)
Indazole is an important scaffold in medicinal chemistry. At present, the progress on synthetic methodologies has allowed the preparation of several new indazole derivatives with interesting pharmacological properties. Particularly, the antiprotozoal activity of indazole derivatives have been recently reported. Herein, a series of 22 indazole derivatives was synthesized and studied as antiprotozoals. The 2-phenyl-2H-indazole scaffold was accessed by a one-pot procedure, which includes a combination of ultrasound synthesis under neat conditions as well as Cadogan’s cyclization. Moreover, some compounds were derivatized to have an appropriate set to provide structure-activity relationships (SAR) information. Whereas the antiprotozoal activity of six of these compounds against E. histolytica, G. intestinalis, and T. vaginalis had been previously reported, the activity of the additional 16 compounds was evaluated against these same protozoa. The biological assays revealed structural features that favor the antiprotozoal activity against the three protozoans tested, e.g., electron withdrawing groups at the 2-phenyl ring. It is important to mention that the indazole derivatives possess strong antiprotozoal activity and are also characterized by a continuous SAR.
Synthesis method of 2H-indazole and derivatives thereof
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Paragraph 0027-0040, (2020/12/15)
The invention discloses a synthetic reaction of 2H-indazole and derivatives thereof under a metal-free condition. The new strategy has the advantages of no metal participation, wide substrate range and good functional group compatibility, and an efficient
Efficient synthesis of 2-aryl-2: H -indazoles by base-catalyzed benzyl C-H deprotonation and cyclization
Gao, Wen-Xia,Jin, Guo-Qing,Liu, Miao-Chang,Wu, Hua-Yue,Zhou, Yun-Bing
, p. 14617 - 14620 (2020/12/02)
A straightforward and efficient method for the preparation of 2-aryl-2H-indazoles from ortho-alkyl substituted azoxybenzenes is presented. The reaction proceeds through base-catalyzed benzyl C-H deprotonation and cyclization to afford 2-aryl-2H-indazoles
Tert-Butyl Hydroperoxide-Mediated Oxo-Sulfonylation of 2 H-Indazoles with Sulfinic Acid toward Indazol-3(2 H)-ones
Ghosh, Payel,Mondal, Susmita,Hajra, Alakananda
supporting information, p. 1086 - 1090 (2020/02/04)
A new and efficient oxo-sulfonylation protocol has been established for the synthesis of N-sulfonylated indazolones employing sulfinic acid as a sulfonylating agent using tert-butyl hydroperoxide (TBHP) under ambient air. A series of structurally diverse 1-sulfonylindazol-3(2H)-one derivatives were obtained in good yields. A radical reaction mechanism has been proposed for this transformation.
Room-Temperature, Metal-Free, and One-Pot Preparation of 2H-Indazoles through a Mills Reaction and Cyclization Sequence
Kondo, Masaru,Takizawa, Shinobu,Jiang, Yuzhao,Sasai, Hiroaki
supporting information, p. 9866 - 9869 (2019/07/10)
The Mills reaction and cyclization of readily available 2-aminobenzyl alcohols and nitrosobenzenes using thionyl bromide provided 2H-indazoles in up to 88 % yields. In the metal-free process, acetic acid played a crucial role for the both Mills reaction and cyclization. A brominated 2H-indazole could also be obtained through the one-pot sequence.
Direct Acyl Radical Addition to 2 H-Indazoles Using Ag-Catalyzed Decarboxylative Cross-Coupling of α-Keto Acids
Bogonda, Ganganna,Kim, Hun Young,Oh, Kyungsoo
, p. 2711 - 2715 (2018/05/22)
A direct acyl radical addition to 2H-indazoles has been achieved for the first time, where the less-aromatic quinonoid 2H-indazoles readily accepted radical species to the C-3 position. Motivated by the lack of direct acylation strategy for 2H-indazoles, the current method utilizes the radical acceptability of 2H-indazoles, discovering an ambient temperature reaction to provide facile access to a diverse array of 3-acyl-2H-indazoles with three points of structural diversification in 25%-83% yields.
A General One-Pot Synthesis of 2H-Indazoles Using an Organophosphorus–Silane System
Schoene, Jens,Bel Abed, Hassen,Schmieder, Peter,Christmann, Mathias,Nazaré, Marc
, p. 9090 - 9100 (2018/06/29)
A simple and direct approach for the regioselective construction of the privileged 2H-indazole scaffold is described. The developed one-pot strategy involves phospholene-mediated N?N bond formation to access 2H-indazoles. The amount of organophosphorus reagent was minimized by recycling the phospholene oxide with organosilane reductants. Starting from functionalized 2-nitrobenzaldehydes and primary amines, a mild reductive cyclization, involving the use of commercially available phospholene oxide and silanes, delivered a wide variety of substituted 2H-indazoles in good to excellent yields.
