89215-26-9

Upstream product

• 74-88-4 methyl iodide 
• 2835-77-0 (2-aminophenyl)(phenyl)methanone 
• 144202-85-7 2-methyl-3-phenyl-3,3a,4,5,6,7-hexahydro-2H-imidazole 
• 4838-00-0 2-methyl-2H-indazole 
• 591-50-4 iodobenzene 
• 1632159-69-3 C₁₄H₁₉BN₂O₂ 
• 124-41-4 sodium methylate 
• 13436-48-1 1-methyl-1H-indazole 
• 109871-16-1 2-oxo-3-phenylindazole 
• 13097-01-3 3-phenyl-1H-indazole 

Relevant academic research and scientific papers

Direct N-Alkylation and Kemp Elimination Reactions of 1-Sulfonyl-1H-Indazoles

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 method was successfully applied to the total syntheses of quindolinone and cryptolepinone; quindolinone was prepared in a one-pot reaction from 1-sulfonyl-1H-indazole.

Multidirectional Synthesis of Substituted Indazoles via Iridium-Catalyzed C-H Borylation

In the absence of a steric directing group, iridium-catalyzed C-H borylation of N-protected indazoles occurs rapidly and selectively at C-3 and the resulting boronate esters can be utilized in a range of downstream conversions. The functional group tolera

A robust protocol for Pd(ii)-catalyzed C-3 arylation of (1H) indazoles and pyrazoles: Total synthesis of nigellidine hydrobromide

C3-arylated indazole and pyrazoles are privileged structural motifs in agrochemicals and pharmaceuticals. C-3 C-H arylation of (1H) indazole and pyrazole has been a significant challenge due to the poor reactivity of the C-3 position. Herein, we report a practical Pd(ii)/Phen catalyst and conditions for the direct C-3 arylation of indazole and pyrazole with ArI or ArBr without using Ag additives as halide scavengers. The use of toluene, chlorobenzene, trifluoromethylbenzene and mesitylene as the solvent was found to be crucial for the selectivity and reactivity. We further demonstrate the robustness of this protocol through the first total synthesis of nigellidine hydrobromide as well as the expedient preparation of heterocycles structurally related to pesticides and drug molecules.

Pd- and Cu-catalyzed C-H arylation of indazoles

The palladium- and copper-catalyzed C-H arylation reactions of 1H- and 2H-indazoles with haloarenes are described. A PdCl2/phen/Ag 2CO3/K3PO4 catalytic system is effective for the C-H arylation of 1H- and 2H-indazoles with haloarenes, whereas a less expensive CuI/phen/LiOt-Bu catalytic system is applicable to the C-H coupling of substituted 2H-indazoles and iodoarenes. The utility of newly developed catalyst was demonstrated in the rapid synthesis of YC-1 (an antitumor agent) and YD-3 (platelet anti-aggregating agent). These new reactions represent important direct functionalization tools of indazoles, well-known bioisosteres of pharmaceutically important indole core.

Direct arylations of 2H-Lndazoles on water

(Figure presented) The efficient palladium-catalyzed synthesis of a range of substituted 2H-lndazoles via C-H arylation Is reported. Reactions are performed on water and provide a direct and mild route toward 2,3-diaryl Indazoles of widespread biological significance.

Synthesis of hydrogenated indazole derivatives starting with α,β-unsaturated ketones and hydrazine derivatives

The reaction of hydrazine derivatives with α,β-unsaturated ketones, such as cyclohexenyl(phenyl)methanone and (E)-2-benzylidenecyclohexanone, were investigated. The reaction between methylhydrazine and e.g., cyclohexenyl(phenyl)methanone was particularly interesting as 3a,4,5,6,7,7a-hexahydro-1-methyl-3-phenyl-1H-indazole was obtained as the major product together with 4,5,6,7-tetrahydro-2-methyl-3-phenyl-2H-indazole as a minor product.

Polymorphism vs. desmotropy: The cases of 3-phenyl- and 5-phenyl-1H-pyrazoles and 3-phenyl-1H-indazole

Two desmotropes, 3-phenyl-1H-pyrazole (1a) and 5-phenyl-1H-pyrazole (1b) have been isolated and the conditions for their interconversion established. The X-ray structure of 1b has been determined (a = 10.862(1), b = 5.7620(5), c = 12.927(2) A, β = 111.435