6639-93-6

Basic information

• Product Name: 1,2,3,4-TETRAHYDRO-6-METHYLQUINOXALINE
• Synonyms: 1,2,3,4-TETRAHYDRO-6-METHYLQUINOXALINE;6-methyl-1,2,3,4-tetrahydroquinoxaline
• CAS NO: 6639-93-6
• Molecular Formula: C₉H₁₂N₂
• Molecular Weight: 148.20498
• Mol File: 6639-93-6.mol

Chemical Properties

• Boiling Point: 287.5°C at 760 mmHg
• Flash Point: 174.6°C
• Appearance: /
• Density: 1.024g/cm³
• Vapor Pressure: 0.00247mmHg at 25°C
• Refractive Index: 1.539
• CAS DataBase Reference: 1,2,3,4-TETRAHYDRO-6-METHYLQUINOXALINE(CAS DataBase Reference)
• NIST Chemistry Reference: 1,2,3,4-TETRAHYDRO-6-METHYLQUINOXALINE(6639-93-6)
• EPA Substance Registry System: 1,2,3,4-TETRAHYDRO-6-METHYLQUINOXALINE(6639-93-6)

Safety Data

• Hazardous Substances Data: 6639-93-6(Hazardous Substances Data)

Usage

Uses

Used in Pharmaceutical Synthesis:
1,2,3,4-Tetrahydro-6-methylquinoxaline is used as a building block for the synthesis of various pharmaceuticals and bioactive compounds. Its unique structure and properties make it a valuable component in creating new medicines and therapeutic agents.
Used in Medicinal Chemistry:
1,2,3,4-Tetrahydro-6-methylquinoxaline is used as a synthetic intermediate in medicinal chemistry, contributing to the development of novel drug candidates with potential pharmacological properties.
Used in Coordination Chemistry:
As a ligand, 1,2,3,4-tetrahydro-6-methylquinoxaline is used in coordination chemistry to form complexes with metal ions, which can have applications in various fields, including catalysis and materials science.
Used in Organic Synthesis:
1,2,3,4-Tetrahydro-6-methylquinoxaline is employed as a reagent in organic synthesis, facilitating the formation of new chemical entities and aiding in the advancement of chemical research and development.

InChI:InChI=1/C9H12N2/c1-7-2-3-8-9(6-7)11-5-4-10-8/h2-3,6,10-11H,4-5H2,1H3

Upstream product

• 6344-72-5 6-methylquinoxaline 
• 496-72-0 4-methyl-1,2-diaminobenzene 
• 89-62-3 4-methyl-2-nitroaniline 
• 1336-21-6 ammonium hydroxide 
• 106-93-4 ethylene dibromide 

Downstream Products

• 411213-74-6 6-methyl-2,3-dihydro-1,4-methano-quinoxaline 
• 6344-72-5 6-methylquinoxaline 

Relevant articles and documents

Tetrabutylammonium Bromide-Catalyzed Transfer Hydrogenation of Quinoxaline with HBpin as a Hydrogen Source

A metal-free environmentally benign, simple, and efficient transfer hydrogenation process of quinoxaline has been developed using the HBpin reagent as a hydrogen source. This reaction is compatible with a variety of quinoxalines offering the desired tetrahydroquinoxalines in moderate-to-excellent yields with Bu4NBr as a noncorrosive and low-cost catalyst.

Water-involving transfer hydrogenation and dehydrogenation of N-heterocycles over a bifunctional MoNi4 electrode

A room-temperature electrochemical strategy for hydrogenation (deuteration) and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi4 electrode is developed, which includes the hydrogenation of quinoxaline using H2O as the hydrogen source with 80% Faradaic efficiency and the reverse dehydrogenation of hydrogen-rich 1,2,3,4-tetrahydroquinoxaline with up to 99% yield and selectivity. The in situ generated active hydrogen atom (H*) is plausibly involved in the hydrogenation of quinoxaline, where a consecutive hydrogen radical coupled electron transfer pathway is proposed. Notably, the MoNi4 alloy exhibits efficient quinoxaline hydrogenation at an overpotential of only 50 mV, owing to its superior water dissociation ability to provide H* in alkaline media. In situ Raman tests indicate that the NiII/NiIII redox couple can promote the dehydrogenation process, representing a promising anodic alternative to low-value oxygen evolution. Impressively, electrocatalytic deuteration is easily achieved with up to 99% deuteration ratios using D2O. This method is capable of producing a series of functionalized hydrogenated and deuterated quinoxalines.

Cu-Catalyzed Chemoselective Reduction of N-Heteroaromatics with NH3·BH3 in Aqueous Solution

An efficient catalytic system was successfully developed on reduction of N-heteroaromatics with H3N?BH3 as hydrogen source in CuSO4 solution, featuring excellent chemoselectivity as well as very broad functional group tolerance. Various challenging substrates, such as OH-, NH2-, Cl-, Br-, etc., contained quinolines, quinoxalines, 1,5-naphthyridines and quinazolines were all reduced smoothly. Mechanistic studies suggested that [Cu-H] intermediate might be generated from NH3?BH3, which was believed to form with H3N?BH3 in CuSO4 solution.

Homogeneous Hydrogenation with a Cobalt/Tetraphosphine Catalyst: A Superior Hydride Donor for Polar Double Bonds and N-Heteroarenes

The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex-catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24 000 TON and 12 000 h-1 TOF) and excellent chemoselectivities with various aldehydes, ketones, imines, and even N-heteroarenes. The preference for 1,2-reduction over 1,4-reduction makes this method an efficient way to prepare allylic alcohols and amines. Meanwhile, efficient hydrogenation of the challenging N-heteroarenes is also furnished with excellent functional group tolerance. Mechanistic studies and control experiments demonstrated that a CoIH complex functions as a strong hydride donor in the catalytic cycle. Each cobalt intermediate on the catalytic cycle was characterized, and a plausible outer-sphere mechanism was proposed. Noteworthy, external inorganic base plays multiple roles in this reaction and functions in almost every step of the catalytic cycle.

Preparation method of tetrahydroquinoxaline compound

The invention relates to the field of preparation methods of organic compounds, in particular to a preparation method of a tetrahydroquinoxaline compound. According to the method, a quinoxaline compound is used as a reaction substrate; the preparation method comprises the following steps: dissolving a rhodium metal catalyst, zinc powder, an additive or a ligand into a dry solvent in an environmentwhich is not in contact with air, namely a nitrogen or argon environment, then adding the quinoxaline reaction substrate, adding water, reacting the mixture at 40-80 DEG C, monitoring the reaction byusing TLC until the substrate is completely consumed, and purifying residues to obtain a target product. The method has the advantages of cheap and easily available reagents, simple process, convenient operation, strong atom economy, and suitableness for routine preparation.

Rhodium-catalyzed transfer hydrogenation of quinoxalines with water as a hydrogen source

Rhodium-catalyzed transfer hydrogenation of quinoxalines with water as a hydrogen source was reported. The reaction allowed the simple preparation of tetrahydroquinoxalines under mild conditions. The deuterium-labelling experiment confirmed that water is

Versatile (Pentamethylcyclopentadienyl)rhodium-2,2′-Bipyridine (Cp?Rh-bpy) Catalyst for Transfer Hydrogenation of N-Heterocycles in Water

An investigation employing the catalytic system consisting of (pentamethylcyclopentadienyl)rhodium dichloride dimer [Cp?RhCl2]2 and 2,2′-bipyridine (bpy) for transfer hydrogenation of a variety of quinoxalines, quinoxalinones, quinolines and indoles under aqueous conditions with formate as the hydrogen source is reported. This approach provides various tetrahydroquinoxalines, dihydroquinoxalinones, tetrahydroquinolines and indolines in good to excellent yields. The activity of the catalyst towards quinoxalines and quinoxalinones is excellent, with a substrate to catalyst ratio (S/C) of 10000 being feasible. The choice of ligand is critical to the catalysis, and the aqueous phase reduction is shown to be highly pH-dependent, with acidic pH values needed for optimal reduction. The catalyst is easy to access, and the reaction is operationally simple without requiring an inert atmosphere.

Synthesis and single crystal structure of novel 1,4-Bis (Dichloroacetyl)-1,2,3,4-tetrahydroquinoxaline Derivatives

A series of 1,4-bis (dichloroacetyl)-1,2,3,4-tetrahydroquinoxalines (4) were synthesized by cyclization and acylation reactions with o-phenylenediamine and 1,2- dibromoalkanes as the starting materials in the presence of NaHCO3 as attaching acid agent. The structures of all the compounds were characterized by IR, 1H NMR, 13C NMR, MS and elemental analysis. The single crystal of 3a, 4d and 6 were determined by X-ray crystallography.

Robust cyclometallated Ir(iii) catalysts for the homogeneous hydrogenation of N-heterocycles under mild conditions

Cyclometallated Cp*Ir(N∧C)Cl complexes derived from N-aryl ketimines are highly active catalysts for the reduction of N-heterocycles under ambient conditions and 1 atm H2 pressure. The reaction tolerates a broad range of other potentially reducible functionalities and does not require the use of specialised equipment, additives or purified solvent.

The remarkable effect of a simple ion: Iodide-promoted transfer hydrogenation of heteroaromatics

I can do it! Accelerated by simple iodide ions, rhodium-catalysed transfer hydrogenation can be readily performed on quinolines, isoquinolines and quinoxalines, affording the tetrahydro products in high yields with low catalyst loading (see scheme). Copyright