A novelbifunctional organocatalyst library combining both aminocatalysis and phosphonicacid activation was used for the first time as an efficient tool for the stereoselectiveMichaeladdition of aldehydes with several aromatic nitroalkenes with good selectivities up to 95:5 dr and 93:7 er. Due to their high water solubility, the catalysts were easilyrecyclable and could be reused over several cycles
Bifunctional 2,5-Diketopiperazines as Efficient Organocatalysts for the Enantioselective Conjugate Addition of Aldehydes to Nitroolefins
作者:Marco Durini、Florian A. Sahr、Michael Kuhn、Monica Civera、Cesare Gennari、Umberto Piarulli
DOI:10.1002/ejoc.201100794
日期:2011.10
synthesized. DKP-1 and DKP-2 are bifunctional diketopiperazines formally derived from the head-to-tail cyclization of L-aspartic acid and either (R)- or (S)-2,3-diaminopropionic acid, which feature aminomethyl and carboxymethyl side arms in the 3- and 6-positions of the 2,5-piperazindione ring. Peptidomimics (3–6) were tested as organocatalysts in the conjugateaddition of several aldehydes to β-nitrostyrene
Prolylprolinol-Catalyzed Asymmetric Michael Addition of Aliphatic Aldehydes to Nitroalkenes
作者:Dengfu Lu、Yuefa Gong、Weizhou Wang
DOI:10.1002/adsc.200900687
日期:2010.3.8
Several novel prolylprolinol catalysts have been designed and synthesized. This type of compound showed high catalytic efficiency on promoting the direct addition of unmodified aldehydes to nitroalkenes. Among the catalysts surveyed, the least bulky member (8d) exhibited the best performance on both efficiency and stereoselectivity, providing the products with up to 97% ee value with 1.5–5 mol% catalyst
Asymmetric Organocatalysis Accelerated via Self‐Assembled Minimal Structures
作者:Arianna Sinibaldi、Francesca Della Penna、Marco Ponzetti、Francesco Fini、Silvia Marchesan、Andrea Baschieri、Fabio Pesciaioli、Armando Carlone
DOI:10.1002/ejoc.202101042
日期:2021.10.21
Self-assembling minimalistic peptides embedded with an organocatalytic moiety were designed and tested in a Michael reaction as a proof of concept for acceleratedorganocatalysis.
嵌入有机催化部分的自组装简约肽在迈克尔反应中被设计和测试,作为加速有机催化的概念证明。
Peptide-catalyzed stereoselective Michael addition of aldehydes and ketones to heterocyclic nitroalkenes
AbstractStereoselective Michael addition of enolizable carbonyl compounds to a furane-derived nitroalkene was catalyzed by di- and tripeptide organocatalysts. The most competent catalysts were tripeptides possessing Pro–Pro–Glu structure. With aldehydes, Michael adducts were obtained in high yields and with medium-to-high diastereo- (up to 13:1 d.r.) and enantiomeric purities (up to 99% ee). The reaction was less stereoselective