Polystyrene-Supported Diarylprolinol Ethers as Highly Efficient Organocatalysts for Michael-Type Reactions
作者:Esther Alza、Sonia Sayalero、Pinar Kasaplar、Diana Almaşi、Miquel A. Pericàs
DOI:10.1002/chem.201101730
日期:2011.10.4
addition of aldehydes to nitroolefins and of malonates or nitromethane to α,β‐unsaturated aldehydes. The combination of the catalytic unit, the triazole linker, and the polymeric matrix provides unprecedented substrate selectivity, in favor of linear, short‐chain aldehydes, when the organocatalyzed reaction proceeds by an enamine mechanism. High versatility is noted in reactions that proceed via an iminium
Multistep Organocatalysis for the Asymmetric Synthesis of Multisubstituted Aldehydes from Allylic Alcohols
作者:Xuan-Huong Ho、Hyun-Ji Oh、Hye-Young Jang
DOI:10.1002/ejoc.201200863
日期:2012.10
chiral amine organocatalyst induces the formation of multifunctionalized aldehydesfrom aromatic and aliphatic allylicalcohols. Reactions occur with excellent levels of enantioselectivity, under environmentally benign conditions, and without involving stoichiometric amounts of chemical oxidants for the oxidation of the allylicalcohols or rigorous reaction conditions for transition-metal catalysis.
Hollow structural effect of microporous organocatalytic polymers with pyrrolidines: dramatic enhancement of catalytic performance
作者:Kyoungil Cho、Jin Yoo、Hyeong-Wan Noh、Sang Moon Lee、Hae Jin Kim、Yoon-Joo Ko、Hye-Young Jang、Seung Uk Son
DOI:10.1039/c7ta02404e
日期:——
Hollow and microporous organocatalytic polymers bearing pyrrolidines (H-MOP-P) were prepared by template synthesis and post-synthetic modification and showed enhanced performance, compared to nonhollow ones.
An Eco-Friendly Asymmetric Organocatalytic Conjugate Addition of Malonates to α,β-Unsaturated Aldehydes: Application on the Synthesis of Chiral Indoles
作者:Karla Santos Feu、Anna Maria Deobald、Senthil Narayanaperumal、Arlene G. Corrêa、Márcio Weber Paixão
DOI:10.1002/ejoc.201300431
日期:2013.9
synthetic community faces the need to ad-dress growing environmental concerns. To lessen the envi-ronmental impact of organic transformations, all conven-tional synthetic methodologies, including asymmetric syn-thetic protocols, should be reviewed and, if possible, re-placed by new processes that continue to meet the needs ofefficiency, selectivity but that are environmentally benign.
Base-Base Bifunctional Catalysis: A Practical Strategy for Asymmetric Michael Addition of Malonates to α,β-Unsaturated Aldehydes
作者:Yongcan Wang、Pengfei Li、Xinmiao Liang、Jinxing Ye
DOI:10.1002/adsc.200800070
日期:2008.6.9
Lewis base–Brønsted base bifunctional catalysis is a novel and practical strategy for the asymmetricMichaeladdition. The addition of malonates to a series of α,β-unsaturated aldehydes can take place under base–base bifunctional catalytic conditions using 0.5–5 mol% of (S)-2-[diphenyl(trimethylsilyloxy)methyl]pyrrolidine as catalyst and 5–30 mol% of lithium 4-fluorobenzoate as additive base with up