3682-72-2Relevant academic research and scientific papers
Manganese-Catalyzed Electrochemical Tandem Azidation-Coarctate Reaction: Easy Access to 2-Azo-benzonitriles
Maiti, Debabrata,Mahanty, Kingshuk,De Sarkar, Suman
supporting information, 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.
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.
Synthesis method of 2H-indazole and derivatives thereof
-
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
Preparation method 2 - substituted - 222H-indazole compound
-
Paragraph 0049-0051; 0055, (2020/10/19)
The invention provides a preparation method of a 2-substituent-2H-indazole compound. With a cuprous catalyst, a coupling reaction is carried out to substituted 1H-indazole and aryliodonium salt in a low-molecular polar organic solvent to obtain a corresponding 2-substituent-2H-indazole compound, wherein the molar ratio of the 1H-indazole to the aryliodonium salt is 1:1.2. According to the method,the reaction route starts from the 1H-indazole compound which is easy to obtain; with the low-cost cuprous compound as a catalyst, the reaction condition is gentle and yield of produced target compound is high. The method also has good compatibility with various functional groups and can be widely applied to synthesize 2-substituent-2H-indazole compounds having different substituent groups. The method has important application value.
Fe2O3@[proline]–CuMgAl–LDH: A magnetic bifunctional copper and organocatalyst system for one-pot synthesis of quinolines and 2H-indazoles in green media
Esfandiary, Naghmeh,Heydari, Akbar
, (2020/05/25)
A novel magnetic core–shell Fe2O3@[proline]–CuMgAl–L(ayered)D(ouble)H(ydroxide) was designed as an efficient bifunctional catalytic system. To this end, Cu (II) was combined with Mg and Al in the LDH structure and l-proline was intercalated between LDH layers in order to perform a straightforward synthesis of quinolines and 2H-indazoles as two important pharmaceutical N-aryl-substituted heterocyclic compounds. In this regard, a facile method was employed through consecutive condensation under a mild conditions in choline azide media, which played the role of a reagent and a solvent to avoid toxic solvents and hazardous azidation reagents. These techniques provided considerable improvement in terms of using green media, reducing starting materials, reaching higher yields and offering a shorter reaction time and lower temperature. In conclusion, it was found that the catalyst could be reused five times with no significant loss of activity.
Regioselective C3-H Trifluoromethylation of 2 H-Indazole under Transition-Metal-Free Photoredox Catalysis
Murugan, Arumugavel,Babu, Venkata Nagarjuna,Polu, Ashok,Sabarinathan, Nagaraj,Bakthadoss, Manickam,Sharada, Duddu S.
, p. 7796 - 7803 (2019/06/27)
Trifluoromethyl-substituted heteroarenes are biologically active compounds and useful building blocks. In this sequence, we have developed a visible-light-promoted regioselective C3-H trifluoromethylation of 2H-indazole under metal-free conditions, which
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.
Access to 2-substituted-2: H -indazoles via a copper-catalyzed regioselective cross-coupling reaction
Zhang, Rong,Liu, Zheng,Peng, Qiujun,Zhou, Yijun,Xu, Lanting,Pan, Xianhua
, p. 1816 - 1822 (2018/03/23)
A CuCl catalyzed C-N cross-coupling reaction using commercially available 1H-indazoles with diaryliodonium salts is described. The methodology features ample structural versatility, affording 2-substituted-2H-indazole in good yields and complete N(2)-regiocontrol. Furthermore, the utility of the reaction was demonstrated in the synthesis of a known estrogen receptor β agonist. Mechanistic studies using density functional theory calculations suggested that the complete regioselectivity can be attributed to the only weak base TfO- in our system which could not deprotonate indazoles, and the catalyst oxidation process would be the rate-determining step.
Indazolin- S -ylidene-N-heterocyclic carbene complexes of rhodium, palladium, and gold: Synthesis, characterization, and catalytic hydration of alkynes
Zhou, Yang,Liu, Qingjie,Lv, Weifeng,Pang, Qingyu,Ben, Rong,Qian, Yong,Zhao, Jing
supporting information, p. 3753 - 3759 (2013/07/26)
A novel series of Indy-N-heterocyclic carbene ligands (Indy = indazolin-s-ylidene) have been developed and investigated. Via a mild Ag carbene transfer route, these new carbene ligands reacted with rhodium, palladium, and gold salts to yield the correspon
