5582-87-6Relevant articles and documents
Method for high-selectivity reduction of nitroolefin C=C double bonds
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Paragraph 0053-0056; 0061-0063, (2021/06/21)
The invention provides a method for high-selectivity reduction of nitroolefin C=C double bonds. According to the method, a bidentate nitrogen ligand-[Cp* IrCl2] complex is used as the catalyst, nitroolefin can be conveniently converted into nitroalkane, the catalytic efficiency is extremely high, and the substrate conversion rate is 99% or above. The high-purity nitroalkane can be separated through simple extraction, liquid separation and solvent removal under reduced pressure. The selected solvent is water or a mixture of water and a hydrophilic solvent. The method is green, environment-friendly and high in reaction efficiency. The nitroalkane compound prepared by the invention is a very important organic intermediate, and has wide application in the fields of national defense, pesticide, biology, medicine, fine chemical engineering and the like.
Boosting Conjugate Addition to Nitroolefins Using Lithium Tetraorganozincates: Synthetic Strategies and Structural Insights
Dell'Aera, Marzia,Perna, Filippo Maria,Vitale, Paola,Altomare, Angela,Palmieri, Alessandro,Maddock, Lewis C. H.,Bole, Leonie J.,Kennedy, Alan R.,Hevia, Eva,Capriati, Vito
supporting information, p. 8742 - 8748 (2020/07/04)
We report the first transition metal catalyst- and ligand-free conjugate addition of lithium tetraorganozincates (R4ZnLi2) to nitroolefins. Displaying enhanced nucleophilicity combined with unique chemoselectivity and functional group tolerance, homoleptic aliphatic and aromatic R4ZnLi2 provide access to valuable nitroalkanes in up to 98 % yield under mild conditions (0 °C) and short reaction time (30 min). This is particularly remarkable when employing β-nitroacrylates and β-nitroenones, where despite the presence of other electrophilic groups, selective 1,4 addition to the C=C is preferred. Structural and spectroscopic studies confirmed the formation of tetraorganozincate species in solution, the nature of which has been a long debated issue, and allowed to unveil the key role played by donor additives on the aggregation and structure of these reagents. Thus, while chelating N,N,N’,N’-tetramethylethylenediamine (TMEDA) and (R,R)-N,N,N’,N’-tetramethyl-1,2-diaminocyclohexane (TMCDA) favour the formation of contacted-ion pair zincates, macrocyclic Lewis donor 12-crown-4 triggers an immediate disproportionation process of Et4ZnLi2 into equimolar amounts of solvent-separated Et3ZnLi and EtLi.
Palladium(II)-catalyzed conjugate addition of arylsiloxanes in water
Lerebours, Rachel,Wolf, Christian
, p. 2737 - 2740 (2008/02/07)
Equation Presented Palladium-phosphinous acids catalyze the conjugate addition of arylsiloxanes to a wide range of α.β-unsaturated substrates in water microwave-assisted procedure is described that uses 5 mol % of POPd1 to afford /-substituted ketones, aldehydes, esters, nitriles, an nitroalkanes in 83% to 96% yield within 4 h. This method eliminates the need for stoichiometric additives and an excess of arylsiloxane, an does not require an inert atmosphere.