117635-33-3Relevant academic research and scientific papers
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 Michael-type hydroarylation of nitroalkenes using aryltins and sodium tetraarylborates
Ohe, Toshiyuki,Uemura, Sakae
, p. 1423 - 1431 (2007/10/03)
A variety of aryltin compounds and sodium tetraarylborates can be employed for Michael-type hydroarylation reactions of nitroalkenes to afford β-arylnitroalkanes in moderate to good yields in the presence of either LiCl, MgCl2, or CaCl2 and a catalytic amount of palladium(II) salt (0.05 molar amount) in acetic acid. Results show that 50-70% of aryl groups out of all in these aryl compounds can be transferred to the products in this hydroarylation. The addition of a catalytic amount (0.05-0.10 molar amount) of a Lewis acid chloride, BiCl3 or SbCl3, much improves the product yield in some cases.
Synthesis of 1,1-Diaryl-2,2-dimethoxyethanes
Ashwood, Michael S.,Bell, Lawrence A.,Houghton, Peter G.,Wright, Stanley H. B.
, p. 379 - 381 (2007/10/02)
The 1,4-addition of Grignard reagents to β-nitrostyrene to give 1,1-diaryl-2-nitroethanes and their subsequent conversion via a modified Nef reaction into 1,1-diaryl-2,2-dimethoxyethanes (diarylacetaldehyde dimethyl acetals) is described.The scope of the reaction has been briefly explored and one example demonstrated on a large scale.
