motifs in organocatalysis, whereas efficient 1,3‐diamine‐derived organocatalysts are very rare. Herein we report a highly efficient camphor‐1,3‐diamine‐derived squaramideorganocatalyst. Its catalytic activity in Michaeladditions of 1,3‐dicarbonyl nucleophiles to trans‐β‐nitrostyrene derivatives provides excellent enantioselectivities (up to >99% ee).
New bifunctional 1,3‐diamine organocatalysts derived from (+)‐camphoric acid for asymmetric Michael addition of 1,3‐dicarbonyl compounds to nitroolefins
作者:Márcia Rénio、Dina Murtinho、M. Rita Ventura
DOI:10.1002/chir.23424
日期:2022.5
Novel 1,3-diamine-derived bifunctional thiourea and squaramideorganocatalysts were synthesized from (+)-camphoric acid. These catalysts were easily obtained in up to two to five synthetic steps, in a flexible approach that facilitates their structure variation. Their catalytic activity was examined in the asymmetric Michael addition of 1,3-dicarbonyl compounds to several trans-β-nitrostyrenes. Yields
A strategy for designing chiralBrønsted base organocatalysts through noncovalent modification of a chiral dibasic molecule with an achiral phosphoric acid diester is introduced for the first time. Such a molecular modification concept utilizing acid-base interactions may facilitate the on-demand design of asymmetric organocatalysts, as preliminarily demonstrated in this work.
Development of Mefloquine-Based Bifunctional Secondary Amine Organocatalysts for Enantioselective Michael and Friedel–Crafts Reactions
作者:Dawid J. Kucharski、Radosław Suchanek、Rafał Kowalczyk、Przemysław J. Boratyński
DOI:10.1021/acs.joc.3c01791
日期:2024.1.5
The chiral framework based on 11-aminomefloquine has been utilized for the first time to construct bifunctional organocatalysts. These catalysts demonstrate high enantioselectivity in both Michaeladditions and Friedel–Crafts reactions across a variety of substrates, achieving up to >99% ee. The distinctive feature is the incorporation of a secondary amine group, offering unique tight hydrogen-bonding