aminal via C—N bond activation has been established, in which the formation of zwitterionic intermediate through aza‐Michael addition of aminal to nitrodienes or dienones is identified as a key step for the activation of the C—N bond. The efficient strategy has enabled a new palladium‐catalyzed α‐aminomethylation of nitrodienes and dienones via double C—N bond activation. The scope and versatility of the
(2<i>S</i>,5<i>R</i>)-2-Methylaminomethyl-1-methyl-5-phenylpyrrolidine, a chiral diamine ligand for copper(<scp>ii</scp>)-catalysed Henry reactions with superb enantiocontrol
作者:Dagmar Scharnagel、Felix Prause、Johannes Kaldun、Robert G. Haase、Matthias Breuning
DOI:10.1039/c4cc02429j
日期:——
Copper(ii)-complexes of a cis-2-aminomethyl-5-phenylpyrrolidine catalyse enantioselective Henry reactions with extraordinarily high stereocontrol.
铜(II)配合物与顺式-2-氨基甲基-5-苯基吡咯烷催化了具有极高立体控制性的对映选择性亨利反应。
Base-catalyzed reactions enhanced by solid acids: Amine-catalyzed nitroaldol (Henry) reactions enhanced by silica gel or mesoporous silica SBA-15
作者:Kiyoshi Tanemura、Tsuneo Suzuki
DOI:10.1016/j.tetlet.2017.12.050
日期:2018.1
The reactions of various aldehydes with CH3NO2 catalyzed by Et3N, n-C6H13NH2, and Me2N(CH2)2NH2 were accelerated by the addition of silica gel to givearomatic (aliphatic) β-nitroalcohols, aromatic nitroalkenes, and aromatic 1,3-dinitroalkanes, respectively. Mesoporous silica SBA-15 showed higher activity than silica gel for the synthesis of aromatic nitroalkenes by the reactions of the corresponding
first highly enantioselective and regiodivergent conjugate addition of trialkylaluminium reagents to nitrodienes and nitroenynes is described. By a design of the substrate and a fine-tuning of the reaction conditions, it is possible to selectively form the 1,4- or 1,6-adduct. The same combination of catalyst, copper source, and a ferrocene-based phosphine ligand afforded enantioselectivities up to 95%
Enantio- and Regioselective Conjugate Addition of Organometallic Reagents to Linear Polyconjugated Nitroolefins
作者:Matthieu Tissot、Alexandre Alexakis
DOI:10.1002/chem.201300538
日期:2013.8.19
The copper‐catalysed conjugate addition of trialkylaluminium and dialkylzinc reagents to polyconjugated nitroolefins (nitrodiene and nitroenyne derivatives) is reported. A reversed Josiphos ligand L7 allows for the selective 1,4‐ or 1,6‐addition with high enantioselectivities.