15260-65-8Relevant articles and documents
Synthesis and Reduction of 2,2-diaryl-1-nitroethylenes by using a chiral and a non chiral NADH model in the pyrrolopyridine series
Levacher, Vincent,Valque, Claude,Coupa, Sophie,Dupas, Georges,Queguiner, Guy,Bourguignon, Jean
, p. 1211 - 1215 (1996)
Reduction of 2,2-diphenyl-1-nitroethylene (1) and 2-(2-pyridyl)-2-phenyl-1-nitroethylene (5) is achieved by using the NADH model in the pyrrolopyridine series 2a to give 2,2-diphenyl-1-nitroethane (3) and 2-(2-pyridyl)-2-phenyl-1-nitroethane (7) respectively in 40% yield. The asymmetric reduction of 2-(2-pyridyl)-2-phenyl-1-nitroethylene by the chiral NADH model 2b is studied. Thus, 2-(2-pyridyl)-2-phenyl-1-nitroethane (7) is obtained in 15 to 32% yield. The stereocontrol of the reduction proved to be dependent on the amount of magnesium ions.
Chemical Ionization Mass Spectrometry of Doxylamine and Related Compounds
Korfmacher, Walter A.,Holder, Claude L.,Freeman, James P.,Mitchum, Ronald K.,Gosnell, Aubrey B.
, p. 435 - 439 (1985)
The chemical ionization mass spectrometric (CIMS) analysis of doxylamine, N,N-dimethyl-2-ethanamine, and related compounds, using both ammonia and methane as reagent gases, is discussed.The two reagent gases did not produce the same major fragment ion for doxylamine.Mechanisms for the fragmentation of doxylamine under either ammonia or methane CIMS conditions are proposed.The mechanisms explain the obsrevation of an m/z 182 fragment ion for doxylamine analyzed under methane CIMS conditions and an m/z 184 product ion detected under ammonia CIMS conditions.
Reactivity Diversification - Synthesis and Exchange Reactions of Cobalt and Iron 2-Alkenylpyridine/-pyrazine Complexes Obtained by Vinylic C(sp2)-H Activation
Beck, Robert,Camadanli, Sebnem,Fl?rke, Ulrich,Klein, Hans-Friedrich
, p. 2543 - 2559 (2015)
Abstract The reactivity of 2-alkenylpyridine derivatives with trimethylphosphane-supported iron- and cobalt-methyl adducts were investigated and provided a series of C,N-cyclometalated complexes through smooth vinyl C(sp2)-H activation. The rea
Photoenzymatic Hydrogenation of Heteroaromatic Olefins Using ‘Ene’-Reductases with Photoredox Catalysts
Biegasiewicz, Kyle F.,Black, Michael J.,Chung, Megan M.,Hyster, Todd K.,Meichan, Andrew J.,Nakano, Yuji,Sandoval, Braddock A.,Zhu, Tianyu
, p. 10484 - 10488 (2020/04/29)
Flavin-dependent ‘ene’-reductases (EREDs) are highly selective catalysts for the asymmetric reduction of activated alkenes. This function is, however, limited to enones, enoates, and nitroalkenes using the native hydride transfer mechanism. Here we demonstrate that EREDs can reduce vinyl pyridines when irradiated with visible light in the presence of a photoredox catalyst. Experimental evidence suggests the reaction proceeds via a radical mechanism where the vinyl pyridine is reduced to the corresponding neutral benzylic radical in solution. DFT calculations reveal this radical to be “dynamically stable”, suggesting it is sufficiently long-lived to diffuse into the enzyme active site for stereoselective hydrogen atom transfer. This reduction mechanism is distinct from the native one, highlighting the opportunity to expand the synthetic capabilities of existing enzyme platforms by exploiting new mechanistic models.
A compound including phenmethyl phenmethyl hydrogen official functional modification of carbon-carbon double bond or carbonyl method (by machine translation)
-
Paragraph 0043; 0044; 0048, (2018/03/24)
The present invention discloses a compound including phenmethyl phenmethyl hydrogen official functional modification of carbon-carbon double bond or carbonyl of the method, the method is under protective atmosphere, including phenmethyl compound and dimethyl sulfoxide, in the ammonium persulfate and sodium methoxide in the presence of a pot of reaction, to obtain a styrene derivative; or, under the environment of air, including phenmethyl compound and dimethyl sulfoxide, in potassium sulfate and sodium methoxide in the presence of a pot of reaction, to obtain the decoloring derivatives; the method in metallic catalytic, moderate reaction conditions by a one-step reaction in including phenmethyl compound on the phenmethyl hydrogen yield, high selectivity modifying carbon-carbon double bond or carbonyl, simple steps, the procedure is short, low cost, and is favorable for industrial production. (by machine translation)
Catalytic Enantioselective Synthesis of α-Chiral Azaheteroaryl Ethylamines by Asymmetric Protonation
Xu, Chao,Muir, Calum W.,Leach, Andrew G.,Kennedy, Alan R.,Watson, Allan J. B.
supporting information, p. 11374 - 11377 (2018/08/28)
The direct enantioselective synthesis of chiral azaheteroaryl ethylamines from vinyl-substituted N-heterocycles and anilines is reported. A chiral phosphoric acid (CPA) catalyst promotes dearomatizing aza-Michael addition to give a prochiral exocyclic aryl enamine, which undergoes asymmetric protonation upon rearomatization. The reaction accommodates a broad range of N-heterocycles, nucleophiles, and substituents on the prochiral centre, generating the products in high enantioselectivity. DFT studies support a facile nucleophilic addition based on catalyst-induced LUMO lowering, with site-selective, rate-limiting, intramolecular asymmetric proton transfer from the ion-paired prochiral intermediate.
A Lewis Base Catalysis Approach for the Photoredox Activation of Boronic Acids and Esters
Lima, Fabio,Sharma, Upendra K.,Grunenberg, Lars,Saha, Debasmita,Johannsen, Sandra,Sedelmeier, Joerg,Van der Eycken, Erik V.,Ley, Steven V.
, p. 15136 - 15140 (2017/11/20)
We report herein the use of a dual catalytic system comprising a Lewis base catalyst such as quinuclidin-3-ol or 4-dimethylaminopyridine and a photoredox catalyst to generate carbon radicals from either boronic acids or esters. This system enabled a wide range of alkyl boronic esters and aryl or alkyl boronic acids to react with electron-deficient olefins via radical addition to efficiently form C?C coupled products in a redox-neutral fashion. The Lewis base catalyst was shown to form a redox-active complex with either the boronic esters or the trimeric form of the boronic acids (boroxines) in solution.
β-Selective Reductive Coupling of Alkenylpyridines with Aldehydes and Imines via Synergistic Lewis Acid/Photoredox Catalysis
Lee, Katarzyna N.,Lei, Zhen,Ngai, Ming-Yu
, p. 5003 - 5006 (2017/05/04)
Umpolung (polarity reversal) strategies of aldehydes and imines have dramatically expanded the scope of carbonyl and iminyl chemistry by facilitating reactions with non-nucleophilic reagents. Herein, we report the first visible light photoredox-catalyzed β-selective reductive coupling of alkenylpyridines with carbonyl or iminyl derivatives with the aid of a Lewis acid co-catalyst. Our process tolerates complex molecular scaffolds (e.g., sugar, natural product, and peptide derivatives) and is applicable to the preparation of compounds containing a broad range of heterocyclic moieties. Mechanistic investigations indicate that the key step involves single-electron-transfer reduction of aldehydes or imines followed by the addition of resulting ketyl or α-aminoalkyl radicals to Lewis acid-activated alkenylpyridines.
Palladium-Catalyzed Divergent Arylation with Triazolopyridines: One-Pot Synthesis of 6-Aryl-2-α-styrylpyridines
Moon, Youngtaek,Kwon, Soonhyung,Kang, Dahye,Im, Honggu,Hong, Sungwoo
supporting information, p. 958 - 964 (2016/04/05)
We have developed a new strategy for palladium-catalyzed arylation reactions with triazolopyridines, wherein two different chemical transformations (C-3 vs. C-7) are observed by differentiating the substrates using different bases. The reactive palladium carbenoids were directly generated from triazolopyridines and underwent denitrogenative arylations with aryl bromides. Intriguingly, when potassium carbonate was replaced with potassium tert-butoxide, direct C-H arylation occurred at the most acidic position (C-7). Moreover, two different catalytic arylation events were successfully performed in a one-pot sequence, providing a convenient access to 6-aryl-2-α-styrylpyridines.
Manganese-Catalyzed Direct Nucleophilic C(sp2)-H Addition to Aldehydes and Nitriles
Zhou, Bingwei,Hu, Yuanyuan,Wang, Congyang
, p. 13659 - 13663 (2015/11/16)
Herein, a manganese-catalyzed nucleophilic addition of inert C(sp2)-H bonds to aldehydes and nitriles is disclosed by virtue of a dual activation strategy. The reactions feature mild reaction conditions, excellent regio- and stereoselectivity, and a wide substrate scope, which includes both aromatic and olefinic C-H bonds, as well as a large variety of aldehydes and nitriles. Moreover, mechanistic studies shed light on possible catalytic cycles.
