748183-59-7Relevant academic research and scientific papers
Metal-Free Deoxygenation of Chiral Nitroalkanes: An Easy Entry to α-Substituted Enantiomerically Enriched Nitriles
Pirola, Margherita,Faverio, Chiara,Orlandi, Manuel,Benaglia, Maurizio
supporting information, p. 10247 - 10250 (2021/06/18)
A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine).
Light-Enabled Enantiodivergence: Stereospecific Reduction of Activated Alkenes Using a Single Organocatalyst Enantiomer
Hostmann, Theresa,Molloy, John J.,Bussmann, Kathrin,Gilmour, Ryan
supporting information, p. 10164 - 10168 (2019/12/24)
Light-enabled enantiodivergence is demonstrated in which the alkene substrate configuration is manipulated (E → Z) prior to organocatalytic reduction with a chiral thiourea and Hantzsch ester. This allows stereodivergent reduction to be regulated at the substrate level with high fidelity and mitigates the need for a second, enantiomeric catalyst (up to 93:07 and 95:5 er). The synthetic utility of this strategy has been demonstrated in the synthesis of the weight-loss drug (R)-Lorcaserin (Belviq) and a potent AMPA modulator.
Iridium-Catalyzed Enantioselective Hydrogenation of β,β-Disubstituted Nitroalkenes
Liu, Man,Kong, Duanyang,Li, Meina,Zi, Guofu,Hou, Guohua
supporting information, p. 3875 - 3879 (2016/01/25)
A highly efficient, iridium-catalyzed, enantioselective hydrogenation of β,β-disubstituted nitroalkenes has been developed. Using a complex consisting of iridium and (S,S)-f-spiroPhos as the catalyst, a variety of β,β-disubstituted nitroalkenes were successfully hydrogenated to the corresponding chiral nitroalkanes with excellent enantioselectivities (up to 98% ee) and high turnover numbers (TON=1000).
Readily available hydrogen bond catalysts for the asymmetric transfer hydrogenation of nitroolefins
Schneider, Jakob F.,Lauber, Markus B.,Muhr, Vanessa,Kratzer, Domenic,Paradies, Jan
supporting information; experimental part, p. 4323 - 4327 (2011/07/08)
This paper focuses on readily accessible thiourea hydrogen bond catalysts derived from amino acids, whose steric and electronic features are modulated by their degree of substitution at the carbinol carbon center. These catalysts were applied in the asymmetric transfer hydrogenation of nitroolefins furnishing the chiral products in up to 99% yield and 86% enantiomeric excess. The proposed catalyst's mode of action is supported by mechanistic investigations.
Stereochemical analysis of the enzymic reduction of the double bond of α- and β-substituted nitrostyrenes and α-ethoxycinnamaldehyde through deuterium labelling experiments
Brenna, Elisabetta,Fronza, Giovanni,Fuganti, Claudio,Gatti, Francesco G.
experimental part, p. 5077 - 5084 (2010/10/21)
2H NMR studies and comparison with authentic labelled reference compounds prepared from the (Z)-acetamidocinnamic acid 10 and from (Z)-2-ethoxy-3-(4-methoxyphenyl) prop-2-en-1-ol (14), respectively, by catalytic syn reduction with deuterium gas
Chemoselective and enantioselective transfer hydrogenation of Β, Β-disubstituted nitroalkenes catalyzed by a water-insoluble chiral diaminerhodium complex in water
Tang, Yuanfu,Xiang, Jing,Cun, Linfeng,Wang, Yuqin,Zhu, Jin,Liao, Jian,Deng, Jingen
experimental part, p. 1900 - 1905 (2010/11/17)
Asymmetric transfer hydrogenation of Β, Β-disubstituted nitroalkenes catalyzed by a chiral diaminerhodium complex in combination with HCO2NaHCO2H as a hydrogen source in water was successfully realized with high reactivity, excellent chemoselectivity and good enantioselectivity. The metal precursor and pH value of the aqueous solution have a large influence on the reactivity and chemoselectivity. The substituents on the benzene rings and the sulfonyl groups of TsDPEN have significant effects on the enantioselectivity. This catalytic asymmetric transformation is one of the most practical pathways to obtain optically active nitroalkanes.
Cu-catalysed asymmetric 1,4-addition of Me3Al to nitroalkenes. Synthesis of (+)-ibuprofen
Polet, Damien,Alexakis, Alexandre
, p. 1529 - 1532 (2007/10/03)
Trimethylaluminium undergoes enantioselective (ee up to 93%) copper-catalysed Michael addition to various nitroalkenes. Copper thiophenecarboxylate (CuTC) (2 mol %) and 4 mol % of a chiral phosphoramidite ligand are sufficient for a complete and clean reaction. The synthesis of (+)-ibuprofen is described with 82% ee.
Efficient Cu-catalyzed asymmetric conjugate additions of alkylzinc reagents to aromatic and aliphatic acyclic nitroalkenes
Mampreian, Dawn M.,Hoveyda, Amir H.
, p. 2829 - 2832 (2007/10/03)
An efficient and highly enantioselective (up to 95% ee) Cu-catalyzed method for asymmetric conjugate addition (ACA) of alkylzinc reagents to acyclic disubstituted nitroalkenes is presented. Reactions are typically effected at ambient temperature in the presence of 2 mol % chiral dipeptide phosphine and 1 mol % (CuOTf)2·C6H6. Nitroalkenes bearing aromatic as well as aliphatic substituents readily undergo asymmetric additions.
Convenient catalytic, enantioselective conjugate reduction of nitroalkenes using CuF2
Czekelius, Constantin,Carreira, Erick M.
, p. 4575 - 4577 (2007/10/03)
(Chemical equation presented) We document the use of a new catalyst system for the enantioselective conjugate reduction of nitroalkenes utilizing commercially available CuF2 and the bis-phosphine JOSIPHOS as a ligand. This new protocol not only
METHOD FOR PRODUCING AN OPTICALLY ACTIVE NITRO COMPOUND
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Page 17, (2008/06/13)
An optically active nitro compound having two hydrogen atoms on its α-cabon atom and having β-asymmetric carbon atom can be produced by making α, β-unsaturated nitroolefin having a hydrogen atom on its α-cabon atom react with at least two organosilicon compounds having at lest one silicon-hydrogen bond in the molecule in the presence of an asymmetric copper complex, or react with an organosilicon compound having at least one silicon-hydrogen bond in the molecule in the presence of an asymmetric copper complex and water.
