Month: October 2022

On November 17, 2000, Manoharan, Mariappan; De Proft, Frank; Geerlings, Paul published an article.Electric Literature of 34413-35-9 The title of the article was Enhanced Aromaticity of the Transition Structures for the Diels-Alder Reactions of Quinodimethanes: Evidence from ab Initio and DFT Computations. And the article contained the following:

The Diels-Alder reactions of various quinodimethanes with ethylene are studied by means of ab initio MO and d. functional theory (DFT) to show the effect of aromaticity on the reaction path. The calculations reveal that these reactions are both kinetically and thermodynamically much more favored than the prototype butadiene-ethylene Diels-Alder reaction due to the aromatization process in the transition state (TS) and product. A progressive aromaticity gain is noticed during the reaction, and hence the partial π-delocalized peripheral diene ring function is coupled with the six-electron σ,π-delocalized cyclic unit resulting in an enhanced aromaticity of the TS. The magnetic criteria such as magnetic susceptibility exaltation and nucleus independent chem. shift provide definitive evidence for and fully support the aromatization process and the aromaticity of the TS. The extent of σ-π delocalization and the bond make-break at the TS are consistent with each other, and this is strongly influenced by the adjacent π-aromatization process. Moreover, the aromaticity trends in the resulting TSs and products parallel the activation and reaction energies; the extent of aromatization increases with increasing reaction rate and exothermicity. This confirms that aromaticity is the driving factor governing cycloadditions involving quinodimethanes. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Electric Literature of 34413-35-9

The Article related to aromaticity transition state diels alder quinodimethane ab initio dft, Physical Organic Chemistry: Theoretical Organic Chemical Concepts, Including Quantum and Molecular Mechanical Studies and other aspects.Electric Literature of 34413-35-9

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On May 31, 2010, Mohajeri, Afshan; Shahamirian, Mozhgan published an article.Name: 5-Chloroquinoxaline The title of the article was Substituent effect on local aromaticity in mono and di-substituted heterocyclic analogs of naphthalene. And the article contained the following:

A quant. study on local aromaticity has been performed on a series of mono- and di-substituted biheterocycles (quinoline, isoquinoline, quinoxaline, quinazoline). Three electronically based indexes (PDI, ATI, and FLU) have been employed to investigate the substituent effect on the π-electron delocalization in both heterocycle and benzenoid rings. Three typical substituents (Cl, OCH3, and CN) with different inductive and resonance power have been selected. Generally, substituent causes a reduction in aromaticity irresp. of whether it is electron attracting or electron donating. It is shown that the maximum aromaticity exhibits a similar trend of Cl > CN > OCH3 for all the studied rings. Moreover, it is found that the substituent situation with respect to the heteroatom has a significant influence on the aromaticity. It results from our study that in di-substituted derivatives, irresp. of whether the two substituents form a meta or para isomer, they preferably choose the position which leads to the maximum aromaticity character. Copyright © 2009 John Wiley & Sons, Ltd. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Name: 5-Chloroquinoxaline

The Article related to substituent effect local aromaticity substituted heterocyclic naphthalene analog, Physical Organic Chemistry: Theoretical Organic Chemical Concepts, Including Quantum and Molecular Mechanical Studies and other aspects.Name: 5-Chloroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Verbeek, J.; Berends, W.; Van Beek, H. C. A. published an article in 1976, the title of the article was Photochemical hydroxylation of quinoxalines.Category: quinoxaline And the article contains the following content:

Irradiation of quinoxaline (I) in acidic aqueous solution under anaerobic conditions gave 5-hydroxyquinoxaline (II) and the 1,4-dihydroquinoxaline radical cation (III). III was characterized by ESR spectroscopy. Under aerobic conditions II is the only irradiation product formed. The effect of substituents attached to the benzene nucleus of I is analyzed. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Category: quinoxaline

The Article related to photochem hydroxylation quinoxaline, esr dihydroquinoxaline radial cation, Physical Organic Chemistry: Photo- and Irradiation-Induced Reactions, Free Radical-Induced Reactions, Free Radical Reactions and other aspects.Category: quinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On February 28, 1982, McNab, Hamish published an article.Application In Synthesis of 5-Chloroquinoxaline The title of the article was Carbon-13 nuclear magnetic resonance spectra of quinoxaline derivatives. And the article contained the following:

I (R = H, 5-Me, 5-Cl, 5-OMe, 6-Me; 5,6-Me2; R1 = H, 2-Me, 2-Cl, 2-OMe; 2,3-Me2) are prepared by the cyclocondensation of a phenylenediamine with an α-oxoaldehyde or an α,β-diketone; their 13C NMR are assigned by a first order anal. 2,3-(H2N)2C6H3Me was treated with OHCCHO and NaHSO3 in H2O to give I (R = 5-Me, R1 = H). The 13C-H coupling constants are reported for some I. Acceptable additivity of substituent effects is found within the quinoxaline series. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Application In Synthesis of 5-Chloroquinoxaline

The Article related to quinoxaline preparation carbon 13 nmr, glyoxal cyclocondensation aminotoluene, Physical Organic Chemistry: Resonance Spectra (Electron Spin, Nuclear Magnetic and Fourier Transform Nuclear Magnetic, Quadrupole, etc.) and other aspects.Application In Synthesis of 5-Chloroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

He, Yuqin; Zhang, Haide; Wen, Nana; Hu, Rongsuo; Wu, Guiping; Zeng, Ying; Li, Xiong; Miao, Xiaodan published an article in 2018, the title of the article was Effects of maltose and lysine treatment on coffee aroma by flash gas chromatography electronic nose and gas chromatography-mass spectrometry.Recommanded Product: 5,6,7,8-Tetrahydroquinoxaline And the article contains the following content:

BACKGROUND : Arabica coffee is a sub-tropical agricultural product in China. Coffee undergoes a series of thermal reactions to form abundant volatile profiles after roasting, so it loses a lot of reducing sugars and amino acids. Adding carbonyl compounds with amino acids before roasting could ensure the nutrition and flavor of coffee. The technol. is versatile for the development of coffee roasting process. This investigation evaluates the effects of combining maltose and lysine (Lys) to modify coffee aroma and the possibly related mechanisms. Arabica coffee was pretreated with a series of solvent ratios of maltose and Lys with an identical concentration (0.25 mol L-1) before microwave heating. RESULTS : It was found that the combination of maltose and Lys significantly (P ≤ 0.05) influenced quality indexes of coffee (pH and browning degree). Ninety-six aromatic volatiles have been isolated and identified. Twelve volatile profiles revealed the relationship between fragrance difference and compound content in coffee. Moreover, coffee aroma was modified by a large number of volatiles with different chem. classes and character. CONCLUSION : Thus, our results suggest that the combination of reagents changed overall aroma quality through a series of complex thermal reactions, especially the ratio of Lys/maltose over 2:1. © 2017 Society of Chem. Industry. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Recommanded Product: 5,6,7,8-Tetrahydroquinoxaline

The Article related to coffee aroma maltose lysine flash gas chromatog electronic nose, maillard reaction, coffee, electronic nose, lysine, solid-phase microextraction-gas chromatography-mass spectrometry (spme-gc-ms) and other aspects.Recommanded Product: 5,6,7,8-Tetrahydroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On August 31, 2014, Rana, Abhinandan; Kumar Jana, Swapan; Pal, Tanusri; Puschmann, Horst; Zangrando, Ennio; Dalai, Sudipta published an article.Name: 5,6,7,8-Tetrahydroquinoxaline The title of the article was Electrical conductivity and luminescence properties of two silver(I) coordination polymers with heterocyclic nitrogen ligands. And the article contained the following:

The synthesis and X-ray structural characterization of two novel silver(I) coordination polymers, [Ag(NO3)(quin)]n (1) and [Ag8(HL)2(H2O)4(mpyz)]·3H2O (2) are reported, where quin=5,6,7,8-tetrahydroquinoxaline, H6L=cyclohexane-1,2,3,4,5,6-hexacarboxylic acid and mpyz=2-Me pyrazine. The single crystal diffraction analyses showed that complex 1 is a 2D layered structure, while 2 presents a 3D polymeric architecture. In complex 2 the network is stabilized by argentophilic interactions and hydrogen bonding. Elec. conductivity of order 3 × 10-4 Scm-1 (1) and 1.6 × 10-4 Scm-1 (2) is measured on thin film specimen at room temperature The photoluminescence and thermal properties of the complexes have also been studied. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Name: 5,6,7,8-Tetrahydroquinoxaline

The Article related to silver tetrahydroquinoxaline cyclohexanehexacarboxylate methylpyrazine polymer elec conductivity luminescence, crystal structure silver tetrahydroquinoxaline cyclohexanehexacarboxylate methylpyrazine polymer and other aspects.Name: 5,6,7,8-Tetrahydroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On February 6, 2008, Zhu, Guang; Pang, Keliang; Parkin, Gerard published an article.Safety of 5,6,7,8-Tetrahydroquinoxaline The title of the article was New modes for coordination of aromatic heterocyclic nitrogen compounds to molybdenum: catalytic hydrogenation of quinoline, isoquinoline, and quinoxaline by Mo(PMe3)4H4. And the article contained the following:

The heterocyclic nitrogen compounds (NHetH), isoquinoline (iQH), quinoxaline (QoxH) and quinazoline (QazH), react with Mo(PMe3)6 to give (η2-NHet)Mo(PMe3)4H as a result of cleavage of the C-H bond adjacent to the nitrogen atom. The C-H bond cleavage is reversible, the excess of PMe3 yields the starting compounds back. Furthermore, at elevated temperatures (η2-NHet)Mo(PMe3)4H converts sequentially to isomers of (η6-C,N-NHetH)Mo(PMe3)3 in which the ligand coordinates via the heterocycle, and further, by a haptotropic shift, to (η6-C6-NHetH)Mo(PMe3)3 with coordination via the carbocyclic ring. Isomers of (η6-C,N-NHetH)Mo(PMe3)3 in which the heterocyclic ring coordinated to molybdenum may be hydrogenated, yielding the 1,2,3,4-tetrahydro-derivatives Thus, (η6-C5N-iQH)Mo(PMe3)3 and (η6-C4N2-QoxH)Mo(PMe3)3 react with H2 at 90° to give Mo(PMe3)4H4 and release 1,2,3,4-tetrahydroisoquinoline and 1,2,3,4-tetrahydroquinoxaline, resp. Furthermore, Mo(PMe3)4H4 serves as a catalyst precursor for the hydrogenation of quinoline, isoquinoline, and quinoxaline to the corresponding 1,2,3,4-tetrahydro-heterocycles. The Mo(PMe3)4H4 is the first simple molybdenum complex to effect catalytic hydrogenation of these heterocyclic nitrogen compounds, a necessary step in hydrodenitrogenation. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Safety of 5,6,7,8-Tetrahydroquinoxaline

The Article related to molybdenum trimethylphosphine isoquinoline quinoxaline quinazoline complex preparation haptotropic rearrangement, hydrogenation partial isoquinoline quinoxaline quinazoline molybdenum trimethylphosphine complex and other aspects.Safety of 5,6,7,8-Tetrahydroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On August 17, 2011, Trost, Barry M.; Thaisrivongs, David A.; Hartwig, Jan published an article.Electric Literature of 34413-35-9 The title of the article was Palladium-Catalyzed Asymmetric Allylic Alkylations of Polynitrogen-Containing Aromatic Heterocycles. And the article contained the following:

Nonracemic cyclohexenylmethyl- and cyclopentenylmethyl-substituted nitrogen heterocycles such as I are prepared in 44-93% yields and in 75->99% ee by enantioselective allylic alkylation reactions of cyclohexenyl and cyclopentenyl trimethylbenzoates with methyl-substituted nitrogen heterocycles such as 2-methylpyrazine in the presence of bis(allylpalladium chloride) and a nonracemic dibenzamidodibenzobicyclooctane ligand. Methylated nitrogen-containing aromatic heterocycles such as 2-methylpyrazine, 2-methylpyrimidine, 3-methyl-6-phenylpyridazine, 2-methylquinoxaline, and 1-benzyl-2-methylbenzimidazole are effective reactants. 5,6,7,8-Tetrahydroquinoxaline also undergoes enantioselective allylic alkylation with a cyclohexenyl trimethylbenzoate to give cyclohexenyl tetrahydroquinoxaline II in 99% yield, >99% ee, and in 81:19 diastereoselectivity. The mesityl ester, whose steric bulk prevents competitive deacylation of the electrophile from “hard” nucleophiles, is introduced as a new leaving group in allylic alkylation chem. In contrast to previous studies of enantioselective allylic alkylation reactions with pyridine-based substrates, no precomplexation with a Lewis acid is required before deprotonation of the nucleophiles with LiHMDS, underscoring the relative acidity of these electron-deficient nucleophiles. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Electric Literature of 34413-35-9

The Article related to cyclohexenylmethyl nitrogen heterocycle enantioselective preparation, enantioselective allylic alkylation cyclohexenyl cyclopentenyl mesityl ester nitrogen heterocycle, trimethylbenzoate ester leaving group enantioselective allylic alkylation reaction and other aspects.Electric Literature of 34413-35-9

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On July 3, 2014, Masuda, Naoyuki; Miyamoto, Satoshi; Kikuchi, Shigetoshi; Samizu, Kiyohiro; Sato, Fumie; Shiina, Yasuhiro; Hamaguchi, Wataru; Seo, Tatsushi; Mihara, Takuma published a patent.Safety of 5-Chloroquinoxaline The title of the patent was Preparation of pyrazole compounds as inhibitors of phosphodiesterase 10A. And the patent contained the following:

The title compounds [I; ring A = (un)substituted aromatic heterocyclyl; B = phenylene, pyridinediyl, thiophenediyl, or CC each optionally substituted by ≥1 group selected from C1-6 alkyl, halo, C1-6 alkyloxy, and each (un)substituted cycloalkyl and nonaromatic heterocyclyl; n = 0, 1; L1 = C1-6 alkylene, C1-6 alkylene-T, T-C1-6 alkylene; provided that when n = 0, L1 = trimethylene-T or tetramethylene-T; T = O, S, NH, N(C1-6 alkyl); X = CR0, N; R0 = H, C1-6 alkyl; R1 = H or C1-6 alkyl optionally substituted by ≥1 group selected from halo, HO, C1-6 alkyloxy, cyano, CO2H, and CO2-C1-6 alkyl; ring E = each (un)substituted cycloalkyl, aryl, aromatic heterocyclyl, or nonaromatic heterocyclyl] or salts thereof were prepared These pyrazole compounds have phosphodiesterase 10A (PDE10A)-inhibitory actions, and can be used for the prevention of and/or as therapeutic agents for schizophrenia, anxiety, Huntington’s disease, drug dependence, and/or Alzheimer’s disease. Thus, amidation of 4-[[[1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]oxy]methyl]benzoic acid with 1,2-phenylenediamine using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and Et4N in DMF at room temperature for 1 h followed by cyclization of the resulting amide under heating at 90° for 12 h and salt formation with HCl in EtOAc gave 2-[4-[[[1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]oxy]methyl]phenyl]-1H-benzimidazole (II) dihydrochloride. II.2HCl and compound (III).2HCl showed IC50 of 17 and 0.4 nM, resp., against human PDE10A. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Safety of 5-Chloroquinoxaline

The Article related to pyrazole preparation inhibitor phosphodiesterase 10a pde10a, schizophrenia anxiety huntington disease prevention treatment pyrazole preparation, drug dependence alzheimer disease prevention treatment pyrazole preparation, pyridinylpyrazolyloxymethylphenybenzimidazole preparation inhibitor phosphodiesterase 10a and other aspects.Safety of 5-Chloroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On October 4, 2012, Masuda, Naoyuki; Miyamoto, Satoshi; Kikuchi, Shigetoshi; Samizu, Kiyohiro; Sato, Fumie; Shiina, Yasuhiro; Hamaguchi, Wataru; Seo, Ryushi; Mihara, Takuma published a patent.Quality Control of 5-Chloroquinoxaline The title of the patent was Preparation of pyrazole compounds as inhibitors of phosphodiesterase 10A. And the patent contained the following:

The title compounds [I; ring A = (un)substituted aromatic heterocyclyl; B = phenylene, pyridinediyl, thiophenediyl, or CC each optionally substituted by ≥1 group selected from C1-6 alkyl, halo, C1-6 alkyloxy, and each (un)substituted cycloalkyl and nonaromatic heterocyclyl; n = 0, 1; L1 = C1-6 alkylene, C1-6 alkylene-T, T-C1-6 alkylene; provided that when n = 0, L1 = trimethylene-T or tetramethylene-T; T = O, S, NH, N(C1-6 alkyl); X = CR0, N; R0 = H, C1-6 alkyl; R1 = H or C1-6 alkyl optionally substituted by ≥1 group selected from halo, HO, C1-6 alkyloxy, cyano, CO2H, and CO2-C1-6 alkyl; ring E = each (un)substituted cycloalkyl, aryl, aromatic heterocyclyl, or nonaromatic heterocyclyl] or salts thereof were prepared These pyrazole compounds have phosphodiesterase 10A (PDE10A)-inhibitory actions, and can be used for the prevention of and/or as therapeutic agents for schizophrenia, anxiety, Huntington’s disease, drug dependence, and/or Alzheimer’s disease. Thus, amidation of 4-[[[1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]oxy]methyl]benzoic acid with 1,2-phenylenediamine using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, and Et4N in DMF at room temperature for 1 h followed by cyclization of the resulting amide under heating at 90° for 12 h and salt formation with HCl in EtOAc gave 2-[4-[[[1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]oxy]methyl]phenyl]-1H-benzimidazole (II) dihydrochloride. II.2HCl and compound (III).2HCl showed IC50 of 17 and 0.4 nM, resp., against human PDE10A. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Quality Control of 5-Chloroquinoxaline

The Article related to pyrazole preparation inhibitor phosphodiesterase 10a pde10a, schizophrenia anxiety huntington disease prevention treatment pyrazole preparation, drug dependence alzheimer disease prevention treatment pyrazole preparation, pyridinylpyrazolyloxymethylphenybenzimidazole preparation inhibitor phosphodiesterase 10a and other aspects.Quality Control of 5-Chloroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider