Enantioselective Michael addition of aldehydes to maleimides catalysed by surface-adsorbed natural amino acids

Abstract

Asymmetric Michael addition of carbonyl compounds to N-substituted maleimides is an important method for obtaining optically pure succinimides, which are important chiral fine chemical intermediates. Environmentally friendly and sustainable procedures...

Recent Advancement on the Organocatalyzed Asymmetric Conjugate Addition using Maleimide as a Potential Substrate

“…Further, in continuation to the discussion for Scheme 22 [33] regarding the asymmetric conjugate addition, Szőllősi and coworker also expanded the scope of the reaction by using ketone 46 with N-protected maleimides 3 catalysed by L-phenyl alanine 12 j (Scheme 33). In order to achieve effective outcome, 100 mg of bentolite H were added as an additive in combination with the catalyst for 0.3 mmol reaction scale.…”

“…In 2021, Szőllősi and co‐worker screened L‐phenyl alanine 12 j for the asymmetric conjugate addition of aldehydes 6 with N ‐protected maleimides 3 (Scheme 22). [33] To perform the catalytic reaction, bentolite H was used as an additive in combination with the catalyst for effective result. The products 7′ were obtained with up to 88 % yield and 97 % enantioselectivity.…”

Merging Chiral Diamine and Ni/SiO2 for Heterogeneous Asymmetric 1,4-Addition Reactions

“…34,35 reactions. 36,37 Interestingly, the reactions take place on the surface of the hybrid catalysts, where a surface enhancement effect was observed. Furthermore, Landeros et al intercalated α-amino acid/α,β-dipeptides into the interlamellar space of Mg/Al-hydrotalcites to obtain hybrid chiral catalysts for the asymmetric Michael addition reactions.…”

“…For example, chiral diamine or ( S )-BINOL modified nanocrystalline MgO was used for asymmetric Michael reactions and asymmetric Henry reactions, but only moderate yields and enantioselectivity were obtained . Kobayashi and co-workers modified Rh/Ag bimetallic NPs with chiral dienes or their derivatives for the efficient asymmetric 1,4-addition of α,β-unsaturated ketone/esters with boronic acids. , Szőllősi et al reported the use of organic–inorganic hybrid materials fabricated by in situ adsorbing amino acids on appropriate inorganic oxides in the asymmetric Michael addition reactions. , Interestingly, the reactions take place on the surface of the hybrid catalysts, where a surface enhancement effect was observed. Furthermore, Landeros et al.…”

Asymmetric Conjugate Addition of Ketones to Maleimides Organocatalyzed by a Chiral Primary Amine-Salicylamide

“…The organocatalytic enantioselective conjugate addition reaction of aldehydes to maleimides has been profusely studied [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. However, the same process involving ketones is challenging and has been explored by a limited number of researchers.…”