93086-29-4Relevant articles and documents
Asymmetric Michael reaction between aldehydes and nitroalkanes promoted by pyrrolidine-containing C2-symmetric organocatalysts
Bykova,Kostenko,Kucherenko,Zlotin
, p. 1402 - 1406 (2019/08/12)
Bifunctional C2-symmetric organocatalysts derived from chiral 1,2-diaminoethanes and (S)-2-aminomethylpyrrolidine were fi rst used for promoting the asymmetric Michael addition of aliphatic aldehydes to nitroalkenes. The synthesized enantioenri
Enantioselective Michael Addition of Aldehydes to β-Nitrostyrenes Catalyzed by (S)-N-(D-Prolyl)-1-triflicamido-3-phenylpropan-2-amine
Gorde, Amol B.,Ramapanicker, Ramesh
, p. 4745 - 4751 (2019/08/02)
A new organocatalyst for the asymmetric Michael addition reaction of aldehydes with β-nitrostyrenes is developed by coupling D-proline with (S)-1-triflicamido-3-phenylpropan-2-amine, which in turn is prepared from L-phenylalaninol. The Michael addition pr
Asymmetric conjugate addition of α,α-disubstituted aldehydes to nitroalkenes organocatalyzed by chiral monosalicylamides from trans-cyclohexane-1,2-Diamines
Martínez-Guillén, José R.,Flores-Ferrándiz, Jesús,Gómez, Cecilia,Gómez-Bengoa, Enrique,Chinchilla, Rafael
, (2018/01/18)
Primary amine-salicylamides derived from chiral trans-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugate addition of α,α-disubstituted aldehydes to arylated and heteroarylated nitroalkenes. The reaction is performed in
C2-symmetric sulfonamides as homogeneous and heterogeneous organocatalysts that mimic enzymes in enantioselective Michael additions
Cruz, Harold,Servín, Felipe A.,Madrigal, Domingo,Chávez, Daniel,Perez-Sicairos, Sergio,Aguirre, Gerardo,Cooksy, Andrew L.,Somanathan, Ratnasamy
supporting information, p. 1036 - 1044 (2018/07/29)
Herein, we report the synthesis of C2-symmetric sulfonamides as homogeneous and heterogeneous organocatalysts and their application in the enantioselective conjugate 1,4-Michael addition of carbonylic nucleophiles to β-nitrostyrene. Organocatal
Combining organocatalysis with photoorganocatalysis: photocatalytic hydroacylation of asymmetric organocatalytic Michael addition products
Schiza, Andriana,Spiliopoulou, Nikoleta,Shahu, Adelajda,Kokotos, Christoforos G.
supporting information, p. 18844 - 18849 (2018/11/26)
Organocatalysis and photoorganocatalysis are two areas of synthetic methodology that have found wide applications in organic synthesis. Herein, we report a combination of these two stategies, taking advantage of an organocatalytic Michael addition of α,α-disubstituted aldehydes to maleimides as the first step and a photocatalytic hydroacylation of diisopropyl azodicarboxylate as the second step. Employing an amino acid as the organocatalyst for the asymmetric organocatalytic part and an organic molecule as the photocatalyst, the combination of these two strategies led to the desired products. A number of alkyl- and aryl-substituted maleimides were successfully employed, while the protocol can be used on α,α-disubstituted aldehydes leading to products in moderate to high yields (44-84%) and excellent enantioselectivities (98-100% ee).
Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT)
Lazic, Jelena,Spasic, Jelena,Francuski, Djordje,Tokic-Vujosevic, Zorana,Nikodinovic-Runic, Jasmina,Maslak, Veselin,Djokic, Lidija
, p. 871 - 881 (2016/10/06)
Michael addition of aldehydes to nitro-olefins is an effective method to obtain useful chiral γ-nitroaldehydes. γ-Nitroaldehydes are precursors for chiral γ-aminobutyric acid analogues, which have numerous pharmacological activities and are used for the treatment of neurological disorders. A whole-cell system based on recombinantly expressed 4-oxalocrotonate tautomerase (4-OT) was developed and shown to be an effective biocatalyst for the Michael addition of branched aldehydes to β-nitrostyrenes. The aim of this study was to investigate the influence of the substitution of the N-terminal proline with lysine and arginine, both containing a reactive ε-amino group, on the Michael addition catalyzed by 4-OT. First, the effects of these mutations were examined by in silico analysis, followed by the generation of three terminal lysine mutants. The generated mutants, 4-OT-K, 4-OT-PK and 4-OT-KK were tested for their ability to utilise β-nitrostyrene (1), (E)-1-nitro-2-(2-thienyl)ethene (2) and trans-p-chloro-β-nitrostyrene (3) as Michael acceptors with isobutanal (2-methylpropanal) as the donor. For comparison, the lithium salt of lysine was used in the same organocatalytic reactions. In general, the introduction of lysine had a negative effect on Michael additions based on overall product yields. However, additional lysine residues at the N-terminus of the protein resulted in structural changes that enhanced the activity towards 2 and 3. Therefore, the N-terminal proline is important for 4-OT-catalysed Michael-additions, but it is not essential.
Continuous asymmetric Michael addition of ketones to β-nitroolefins(1R,2R)-(+)-1,2-DPEN-modified sulfonic acid resin
Tian, Jun,Zhang, Chao,Qi, Xuefei,Yan, Xilong,Li, Yang,Chen, Ligong
, p. 724 - 728 (2015/02/19)
A trifunctional catalyst was successfully prepared by bonding (1R,2R)-(+)-1,2-DPEN to sulfonic acid resin. The catalyst was characterized by elemental analysis, thermogravimetric (TG) analysis and infrared (IR) spectroscopy. The results indicated the coex
Enantioselective Michael addition of isobutyraldehyde to nitroalkenes organocatalyzed by chiral primary amine-guanidines
Avila, Angel,Chinchilla, Rafael,Fiser, Béla,Gómez-Bengoa, Enrique,Nájera, Carmen
, p. 462 - 467 (2014/04/17)
Primary amine-guanidines derived from trans-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugate addition of isobutyraldehyde to arylated and heteroarylated nitroalkenes. The reaction was performed in the presence of imi
Synthesis of γ-nitroaldehydes containing quaternary carbon in the α-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst
Radivojevic, Jelena,Minovska, Gordana,Senerovic, Lidija,O'Connor, Kevin,Jovanovic, Predrag,Savic, Vladimir,Tokic-Vujosevic, Zorana,Nikodinovic-Runic, Jasmina,Maslak, Veselin
, p. 60502 - 60510 (2015/11/23)
Synthesis of γ-nitroaldehydes from branched chain aldehydes and a range of α,β-unsaturated nitroalkenes was achieved by a whole-cell biocatalytic reaction using 4-oxalocrotonate tautomerase as catalyst. Under mild conditions, cyclic and acyclic branched a
Chiral picolylamines for Michael and aldol reactions: Probing substrate boundaries
Nugent, Thomas C.,Bibi, Ahtaram,Sadiq, Abdul,Shoaib, Mohammad,Umar, M. Naveed,Tehrani, Foad N.
supporting information, p. 9287 - 9294,8 (2012/12/12)
Here we report on inroads concerning increased substrate breadth via the picolylamine organocatalyst template, a vicinal chiral diamine based on a pyridine-primary amine motif. The addition of cyclohexanone to β-nitrostyrene has many catalyst solutions, b