13436-48-1

Usage

Uses

Used in Pharmaceutical Industry:
1-Methylindazole is used as a key intermediate in the synthesis of pharmaceuticals for its ability to contribute to the development of new drugs with potential therapeutic applications.
Used in Agrochemical Industry:
In the agrochemical sector, 1-methylindazole is utilized as a precursor in the production of agrochemicals, aiding in the creation of compounds that can enhance crop protection and yield.
Used in Dye Industry:
1-Methylindazole is employed as a building block in the synthesis of dyes, contributing to the development of colorants for various applications, including textiles and printing inks.
Used as a Solvent:
Due to its solvent properties, 1-methylindazole is used in various chemical processes where a suitable solvent is required for dissolving substances or facilitating reactions.
Used as a Corrosion Inhibitor:
1-Methylindazole serves as a corrosion inhibitor in industrial applications, helping to protect materials from degradation and extending their service life.
Used in Rubber and Plastics Manufacturing:
In the manufacturing of rubber and plastic products, 1-methylindazole is utilized to enhance the properties of these materials, such as durability and flexibility.
Safety Precautions:
Given its moderately toxic nature, 1-methylindazole may cause irritation to the eyes, skin, and respiratory system. It is crucial to handle 1-methylindazole with proper safety measures, including the use of personal protective equipment and working in a well-ventilated area to minimize exposure risks.

InChI:InChI=1/C8H8N2/c1-10-8-5-3-2-4-7(8)6-9-10/h2-6H,1H3

Upstream product

• 271-44-3 benzimidazole 
• 74-88-4 methyl iodide 
• 50890-83-0 1-methyl-1H-indazole-3-carboxylic acid 
• 32829-25-7 2-(1H-indazol-1-yl)acetic acid 
• 326474-67-3 3-bromo-1-methyl-1H-indazole 
• 64-19-7 acetic acid 
• 52088-10-5 3-iodo-1-methyl-1H-indazole 
• 6630-33-7 ortho-bromobenzaldehyde 
• 141-32-2 acrylic acid n-butyl ester 
• 23300-99-4 1-tosyl-1H-indazole 
• 124-41-4 sodium methylate 

Downstream Products

• 465529-57-1 5-bromo-1-methyl-1H-indazole 
• 52088-11-6 3,5-Dibrom-1-methylindazol 
• 1859-76-3 2-(methylamino)benzophenone 
• 51093-42-6 1‐methyl‐3‐phenyl‐1H‐indazole 
• 1429864-75-4 1-methyl-3-(m-tolyl)-1H-indazole 
• 89215-26-9 2-methyl-3-phenyl-2H-indazole 
• 1429864-74-3 1-methyl-3-(o-tolyl)-1H-indazole 
• 51093-44-8 3‐(4‐methoxyphenyl)‐1‐methyl‐1H‐indazole 
• 329220-10-2 3-(4-fluorophenyl)-1-methyl-1H-indazole 
• 326474-67-3 3-bromo-1-methyl-1H-indazole 
• 16778-51-1 1-(4-nitrophenyl)-1H-indazole 
• 1071433-05-0 1-methyl-1H-indazole-4-carboxylic acid 
• 1627722-97-7 1-methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indazole 
• 680612-97-9 4-(1-methyl-1H-indazol-3-yl)phenol 

Relevant academic research and scientific papers

Pd-Catalyzed C-H Annulation of Five-Membered Heteroaryl Halides with Norbornene Derivatives

Complementary to Catellani-type reactions and 1:1 coupling of six-membered halo(hetero)arenes and norbornene (NBE) derivatives, Pd-catalyzed 1:2 coupling of five-membered haloheteroarenes with NBEs was achieved to afford rigid nonplanar heterocycles. Pyra

A general synthesis of diversely substituted indazoles and hetero-aromatic derivatives from o-halo-(het)arylaldehydes or -phenones

A set of variously substituted indazoles and hetero-aromatic derivatives were synthesized from o-halo-(het)arylaldehydes using a palladium catalyzed amination followed by cyclization. Starting from phenones, this process was extended to give 3-substituted indazoles. Moreover, N-1-substituted-indazoles can be reached by this strategy using an optional selective N-1-alkylation step during the process. This methodology offers a general and easy route for the synthesis of regioselectively substituted indazoles.

Hetero-dicarbene complexes of palladium(II): Syntheses and catalytic activities

A series of Pd(II) dibromido complexes 2-6 bearing cis-chelating hetero-dicarbenes, which contain two different types of NHCs linked by a propylene chain, have been synthesized. In most cases, the N-methylbenzimidazolin-2-ylidene moiety was kept as one NHC donor, while the other one varies with different heterocyclic backbones. As an exception, the hetero-diNHC in complex 8 is derived by combining 1,2,4-triazole and indazole precursors instead. Analogous complexes 9-17, carrying more labile CF3CO2- or CH3CN ligands, were synthesized by reacting the aforementioned bromido complexes with AgO2CCF3 or AgOTf in CH3CN. A systematic catalytic comparison of 9-17 in the direct arylation of pentafluorobenzene with 4-chlorobromobenzene was carried out, and complexes that contain bulkier and less electron-donating ligands were found to be more active. Complex 12, carrying the mesitylimidazolin-2-ylidene unit, proved to be the most efficient, and its activity was also tested in the direct arylation of tetrafluorobenzenes.

Novel synthesis of indazoles from (η6-arene)tricarbonylchromium complexes

Indazole chromium complexes and some of its derivatives were synthesised by two strategies: (1) by cyclisation of [η 6-2-(2′-phenylhydrazine)-1,3-dioxolane]tricarbonylchromium (2) in acidic conditions which was converted into σ-complex (11); (2) by thermolysis of Cr(CO)6 with 1-bis(trimethylsilyl)methylindazole (3) and 2-bis(trimethylsilyl)methyl-3-trimethyl-silylindazole (4), using bulky protecting groups at N(1) or simultaneously at N(2) and C(3), to afford [η6-1-bis(trimethylsilyl)methylindazole]tricarbonylchromium (14) and [η 6-2-bis(trimethylsilyl)methyl-3-trimethylsilylindazole] tricarbonylchromium (15), respectively. The deprotonation of complex 14 followed by electrophilic quench occurs at the C(4) and C(7) positions in a ratio of 3:1 and with complex 15 the deprotonation was completely regioselective at the C(7) position. The position of this substitution was confirmed by n.O.e. difference spectroscopy and X-ray crystal structure determination of the [η 6-2-bis(trimethylsilyl)methyl-7-methyl-3-trimethylsilylindazole] tricarbonylchromium (5). These complexes were decomplexed to produce new substituted indazole derivatives in good yield.

Amine-functionalized indazolin-3-ylidene complexes of palladium(II) by postmodification of a single precursor

A series of five trans-[PdBr2(amine)(indy)] complexes (amine = diethylamine, dipropylamine, dibutylamine, diisobutylamine, morpholine; indy = indazolin-3-ylidene) with pendant teriary amine functionalities in the side chain of the NHC ligand has been prepared by postcoordinative modification of a single bromoalkyl-functionalized precursor complex. This approach allows for a synthesis of functionalized N-heterocyclic carbene complexes more efficient than the metalation of prefunctionalized azolium salts. All complexes have been fully characterized, and the molecular structures of three complexes are reported. A correlation exists between the 13C NMR shift of C carbene and the pKb values of the coordinated amines. Furthermore, all complexes were found to be active catalysts for the direct arylation of 1-methylpyrrole with good to excellent yields.

“On Water” Palladium Catalyzed Direct Arylation of 1H‐Indazole and 1H‐7‐Azaindazole

The C3 direct arylation of 1H-indazole and 1H-7-azaindazole has been a significant challenge due to the lack of the reactivity at this position. In this paper, we describe a mild and an efficient synthesis of new series of C3-aryled 1H-indazoles and C3-aryled 1H-7-azaindazoles via a C3 direct arylation using water as solvent. On water, PPh3 was effective as a ligand along with a lower charge of the catalyst Pd(OAc)2 (5 mol%) at 100 oC, leading to C3-aryled 1H-indazoles or C3-aryled 1H-7-azaindazoles in moderate to good yields.

Palladium-Catalyzed Oxidative Arylation of 1H-Indazoles with Arenes

A simple method for the direct Pd(OAc)2-catalyzed oxidative arylation of inactivated 1H-indazole derivatives with simple arenes is reported. This method exhibits good reaction efficiency and good functional-group tolerance. Using the developed method, 28 arylated products were prepared in yields up to 80 %.

An Effective Method for the Synthesis of 1,3-Dihydro-2H-indazoles via N-N Bond Formation

The [4+1] cycloaddition reaction of bifunctional amino reagents has been achieved with in situ formed aza-ortho-quinone methides. Specifically, N-(tosyloxy)carbamates were used as an N1 synthon and bifunctional amino reagents for this transformation, which provides a metal-free, catalyst-free, and oxidant-free strategy to form nitrogen-nitrogen bonds. (Figure presented.).

Alkylation method for nitrogen-hydrogen containing compounds and application thereof

The invention discloses an alkylation method for nitrogen-hydrogen containing compounds and an application thereof, belonging to the technical field of synthesis of organic compounds. The invention provides a series of methods for a nitrogen alkylation reaction of N-H containing heterocyclic compounds (II) with N,N-dimethylformamide dialkyl acetal as an alkyl source under the condition of no participation of metals, and a product with a hydrogen atom on a nitrogen atom substituted by R1 is obtained. The method provided by the invention has the advantages of highly-efficient reaction, high yield, simple treatment after the reaction, simple and convenient operation, mild reaction conditions, no participation of the metals, high tolerance of functional groups of a reaction substrate, wide range and easy preparation of the substrate, high reaction efficiency after amplification of the reaction, and applicability to large-scale industrial production.

Solvent-Controlled, Site-Selective N-Alkylation Reactions of Azolo-Fused Ring Heterocycles at N1-, N2-, and N3-Positions, Including Pyrazolo[3,4- d]pyrimidines, Purines, [1,2,3]Triazolo[4,5]pyridines, and Related Deaza-Compounds

Alkylation of 4-methoxy-1H-pyrazolo[3,4-d]pyrimidine (1b) with iodomethane in THF using NaHMDS as base selectively provided N2-methyl product 4-methoxy-2-methyl-2H-pyrazolo[3,4-d]pyrimidine (3b) in an 8/1 ratio over N1-methyl product (2b). Interestingly, conducting the reaction in DMSO reversed selectivity to provide a 4/1 ratio of N1/N2 methylated products. Crystal structures of product 3b with N1 and N7 coordinated to sodium indicated a potential role for the latter reinforcing the N2-selectivity. Limits of selectivity were tested with 26 heterocycles which revealed that N7 was a controlling element directing alkylations to favor N2 for pyrazolo- and N3 for imidazo- and triazolo-fused ring heterocycles when conducted in THF. Use of 1H-detected pulsed field gradient-stimulated echo (PFG-STE) NMR defined the molecular weights of ionic reactive complexes. This data and DFT charge distribution calculations suggest close ion pairs (CIPs) or tight ion pairs (TIPs) control alkylation selectivity in THF and solvent-separated ion pairs (SIPs) are the reactive species in DMSO.