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
Translating the Enantioselective Michael Reaction to a Continuous Flow Paradigm with an Immobilized, Fluorinated Organocatalyst
作者:Irina Sagamanova、Carles Rodríguez-Escrich、István Gábor Molnár、Sonia Sayalero、Ryan Gilmour、Miquel A. Pericàs
DOI:10.1021/acscatal.5b01746
日期:2015.11.6
enantioselective, continuous flow processes allowing either the multigram synthesis of a single Michael adduct over a 13 h period or the sequential generation of a library of enantiopure Michael adducts from different combinations of substrates (13 examples, 16 runs, 18.5 h total operation). A customized in-line aqueous workup, followed by liquid–liquid separation in flow, allows for product isolation
Epiandrosterone-derived prolinamide as an efficient asymmetric catalyst for Michael addition reactions of aldehydes to nitroalkenes
作者:Yongchao Wang、Shen Ji、Kun Wei、Jun Lin
DOI:10.1039/c4ra03075c
日期:——
Epiandrosterone derivatives-organocatalyzed asymmetricMichaeladdition of aldehydes to nitroalkenes was investigated. Among the various catalysts, a novel type of epiandrosterone-derived L-prolineamide catalyst was synthesized and exhibited better performance in both catalytic activity and stereoselectivity, providing the products with high yields (up to 98%), excellent enantioselectivities (up to
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