Primary amino acid lithium salt as a catalyst for asymmetric Michael addition of isobutyraldehyde with β-nitroalkenes
作者:Atsushi Sato、Masanori Yoshida、Shoji Hara
DOI:10.1039/b814804j
日期:——
Phenylalanine lithium salt was found to be an effective catalyst for asymmetricMichaeladdition of isobutyraldehyde with beta-nitroalkenes to give quaternary carbon-containing nitroalkanes.
Asymmetric Conjugate Addition of α,α-Disubstituted Aldehydes to Nitroalkenes Organocatalyzed by Chiral Monosalicylamides from trans-Cyclohexane-1,2-Diamines
Primary amine-salicylamides derivedfrom chiral trans-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugateaddition of α,α-disubstituted aldehydes to arylated and heteroarylated nitroalkenes. The reaction is performed in the presence of 4-dimethylaminopyridine as an additive in dichloromethane as a solvent at room temperature. The corresponding enantioenriched γ-nitroaldehydes
Enantioselective Michael Addition of Aldehydes to β-Nitrostyrenes Catalyzed by (S)-<i>N</i>
-(D-Prolyl)-1-triflicamido-3-phenylpropan-2-amine
作者:Amol B. Gorde、Ramesh Ramapanicker
DOI:10.1002/ejoc.201900719
日期:2019.8.7
A D‐prolinamide containing a triflicamide group as the H‐bond donor was developed to catalyze the asymmetricMichaeladdition of β‐nitroalkenes with aldehydes. Very high enantioselectivity and yields are achieved using 10 mol% of the catalyst at r.t. in toluene.
Asymmetric Michael reaction between aldehydes and nitroalkanes promoted by pyrrolidine-containing C2-symmetric organocatalysts
作者:K. A. Bykova、A. A. Kostenko、A. S. Kucherenko、S. G. Zlotin
DOI:10.1007/s11172-019-2568-2
日期:2019.7
Bifunctional C2-symmetric organocatalysts derived from chiral 1,2-diaminoethanes and (S)-2-aminomethylpyrrolidine were fi rst used for promoting the asymmetricMichael addition of aliphatic aldehydes to nitroalkenes. The synthesized enantioenriched (up to 82% ee) products can be transformed into various biologically active γ-aminobutyric acid derivatives.