17418-09-6Relevant articles and documents
Resin-supported acid- and base-catalyzed one-pot sequential reaction including an enantioselective step
Akagawa, Kengo,Sakamoto, Seiji,Kudo, Kazuaki
, p. 985 - 987 (2007)
One-pot sequential acidic deacetalization and basic enantioselective aldol reaction were realized using Amberlite IR-120 (H+-form) and a resin-supported peptide catalyst, and the reusability of the catalysts was demonstrated.
Dual stereocontrol in aldol reactions catalysed by hydroxyproline derivatives in the presence of a large amount of water
Gurka, András A.,Sz?ri, Kornél,Bartók, Mihály,London, Gábor
, p. 936 - 942 (2016)
Parameters influencing dual stereocontrol in aldol reactions of water miscible acetone with aromatic aldehydes in the presence of a large amount of water using hydroxyproline based catalysts were studied. Stereocontrol was achieved by changing the acidity and basicity of the reaction media by the addition of achiral salts in the presence of a single chiral catalyst. Under acidic conditions (NH4Cl salt) the (R)-aldol product was formed in excess while basic aqueous media (carboxylate salts) led to the enrichment of the (S)-enantiomer. Reaction conditions under which the reaction is feasible were optimised and the effect of the structure of the hydroxyproline-based catalysts was investigated. The results show that the formation of a biphasic micellar system and the presence of an appropriate catalyst are both crucial for the reaction to occur. Although the catalyst structure influenced the formation and stabilisation of the micellar system to a large extent, its effect on the enantioselectivities were found to be less pronounced.
Accelerating the optimization of enzyme-catalyzed synthesis conditionsviamachine learning and reactivity descriptors
Liang, Jinhu,Liu, Dongchang,Wan, Zhongyu,Wang, Quan-De
supporting information, p. 6267 - 6273 (2021/07/28)
Enzyme-catalyzed synthesis reactions are of crucial importance for a wide range of applications. An accurate and rapid selection of optimal synthesis conditions is crucial and challenging for both human knowledge and computer predictions. In this work, a
Continuous Flow Synthesis of Quinolines via a Scalable Tandem Photoisomerization-Cyclization Process
Di Filippo, Mara,Baumann, Marcus
, p. 6199 - 6211 (2020/08/26)
A continuous photochemical process is presented that renders a series of quinoline products via an alkene isomerization and cyclocondensation cascade. It is demonstrated that a high-power LED lamp generates the desired targets with higher productivity and efficiency than a medium-pressure Hg-lamp. The scope of this tandem process is established and allows for the generation of various substituted quinolines in high yields and with throughputs of greater than one gram per hour. Finally, this effective flow process is coupled with a telescoped hydrogenation reaction to render a series of tetrahydroquinolines including the antimalarial natural product galipinine.
MnO2as a terminal oxidant in Wacker oxidation of homoallyl alcohols and terminal olefins
Fernandes, Rodney A.,Ramakrishna, Gujjula V.,Bethi, Venkati
, p. 6115 - 6125 (2020/10/27)
Efficient and mild reaction conditions for Wacker-type oxidation of terminal olefins of less explored homoallyl alcohols to β-hydroxy-methyl ketones have been developed by using a Pd(ii) catalyst and MnO2 as a co-oxidant. The method involves mild reaction conditions and shows good functional group compatibility along with high regio- and chemoselectivity. While our earlier system of PdCl2/CrO3/HCl produced α,β-unsaturated ketones from homoallyl alcohols, the present method provided orthogonally the β-hydroxy-methyl ketones. No overoxidation or elimination of benzylic and/or β-hydroxy groups was observed. The method could be extended to the oxidation of simple terminal olefins as well, to methyl ketones, displaying its versatility. An application to the regioselective synthesis of gingerol is demonstrated.
Bioinspired Catalysis: Self-Assembly of a Protein and DNA as a Catalyst for the Aldol Reaction in Aqueous Media
Liu, Hongxin,Li, Guangxun,Wang, Ying-Wei,Zhang, Shiqi,Tang, Zhuo
supporting information, p. 560 - 565 (2017/12/28)
An interesting bioinspired catalyst formed from readily available DNA and a protein through electrostatic interaction in situ proved to be efficient in catalyzing aldol reactions under mild conditions in water. By using a self-assembling catalytic system
Applications of Selenonium Cations as Lewis Acids in Organocatalytic Reactions
He, Xinxin,Wang, Xinyan,Tse, Ying-Lung (Steve),Ke, Zhihai,Yeung, Ying-Yeung
supporting information, p. 12869 - 12873 (2018/09/14)
The use of trisubstituted selenonium salts as organic Lewis acids in electrophilic halogenation and aldol-type reactions has been developed. The substrate scope is broad. The reaction conditions are mild and compatible with various functionalities. This study opens a new avenue for the development of nonmetallic Lewis acid catalysis.
Blue-light-promoted carbon-carbon double bond isomerization and its application in the syntheses of quinolines
Chen, Xinzheng,Qiu, Shuxian,Wang, Sasa,Wang, Huifei,Zhai, Hongbin
supporting information, p. 6349 - 6352 (2017/08/10)
A blue-light-promoted carbon-carbon double bond isomerization in the absence of any photoredox catalyst is reported. It provides rapid access to a series of quinolines in good to excellent yields under simple aerobic conditions. The protocol is direct, catalyst-free and operationally convenient.
Application of Deep Eutectic Solvents in Promiscuous Lipase-Catalysed Aldol Reactions
González-Martínez, Daniel,Gotor, Vicente,Gotor-Fernández, Vicente
supporting information, p. 1513 - 1519 (2016/04/05)
The application of deep eutectic solvents has been demonstrated for the first time in promiscuous lipase-catalysed aldol reactions. The model reaction between 4-nitrobenzaldehyde and acetone was examined in depth, with excellent compatibility being found between porcine pancreas lipase and choline chloride/glycerol mixtures for the formation of the aldol product in high yields. The system was compatible with a series of aromatic aldehydes and ketones including acetone, cyclopentanone and cyclohexanone. In some cases, the corresponding α,β-unsaturated carbonyl compounds were found as minor products. Control experiments demonstrate that the enzymatic preparation was also responsible for a collateral dehydration reaction once the aldol product is formed. Deep eutectic solvents are used for the first time in promiscuous lipase-catalysed aldol reactions. The reaction between substituted benzaldehydes and aliphatic ketones has excellent compatibility with porcine pancreas lipase (PPL) and choline chloride/glycerol mixtures and gives the aldol product in high yields. PPL was also responsible for a collateral dehydration reaction.
Catalyst-free aldol reaction in a water medium
Yao, Weirong,Cui, Yanli,Wang, Peipei,Mao, Yangyi
, p. 293 - 296 (2016/05/24)
Background: With growing interest in developing environmentally friendly reactions and atom-economic processes in recent years, the utilization of water as a solvent has attracted a great deal of attention. This is not only for its low-cost, safe and envi
