1186327-76-3Relevant academic research and scientific papers
Nanocellulose enriches enantiomers in asymmetric aldol reactions
Habaki, Xin,Kanomata, Kyohei,Kitaoka, Takuya,Ranaivoarimanana, Naliharifetra Jessica,Uto, Takuya,Yui, Toshifumi
, p. 37064 - 37071 (2020)
Cellulose nanofibers obtained from wood pulp by TEMPO-mediated oxidation acted as a chiral enhancer in direct aldol reactions of 4-nitrobenzaldehyde and cyclopentanone with (S)-proline as an organocatalyst. Surprisingly, catalytically inactive TEMPO-oxidi
(L)-Prolinamide imidazolium hexafluorophosphate ionic liquid as an efficient reusable organocatalyst for direct asymmetric aldol reaction in solvent-free condition
Yadav, Geeta Devi,Singh, Surendra
, p. 100459 - 100466 (2016/11/09)
We have designed a new hydrophobic ionic liquid derived from bromoester of trans-4-hydroxy-(l)-prolinamide and N-methylimidazole. (l)-Prolinamide imidazolium hexafluorophosphate ionic liquid (2 mol%) found to be an excellent organocatalyst for direct asymmetric aldol reaction between 4-nitrobenzaldehyde and cyclohexanone using acetic acid (2 mol%) as an additive at -15 °C in solvent-free condition, the aldol product was afforded in excellent yield with diastereomeric ratio (anti/syn; 97:3) and 94% ee of anti-aldol product. Ionic liquids can catalyze the direct aldol reaction between benzaldehyde derivatives and cycloalkanones and the best dr (anti/syn; 99.9/0.01) and 99% ee was obtained for aldol product of 2-trifluoromethyl benzaldehyde and cyclohexanone. (l)-Prolinamide imidazolium hexafluorophosphate ionic liquid was reused up to 6 continuous cycles without decrease in the conversion of the product with 92% ee and found to be superior than its counterpart trans-4-hydroxy-(l)-prolinamide. Continuous cycle experiments do not require isolation of the catalyst after each cycle. The results of reusability of the ionic liquid catalyst were found to be better than most of other reported reusable catalysts.
Aerobic photooxidative direct asymmetric aldol reactions of benzyl alcohols using water as the solvent
Fujiya,Nobuta,Yamaguchi,Tada,Miura,Itoh
, p. 39539 - 39543 (2015/05/20)
We report an aerobic photooxidative direct asymmetric aldol reaction using water as the solvent. In this reaction, primary benzyl alcohols are oxidized into benzaldehydes under an oxygen atmosphere using anthraquinone-2-sodium sulfonate monohydrate as an organophotocatalyst. Stereoselective aldol reactions then proceed using a proline-type organocatalyst.
Pepsin-catalyzed direct asymmetric aldol reactions for the synthesis of vicinal diol compounds
Li, Ling-Yu,Yang, Da-Cheng,Guan, Zhi,He, Yan-Hong
, p. 1659 - 1667 (2015/05/26)
The catalytic promiscuity of pepsin from porcine gastric mucous was observed in catalysis of the direct asymmetric aldol reactions of aromatic aldehydes with acetones, which were substituted by hydroxy-, dihydroxy-, methoxy- and benzyloxy- for the synthes
Intramolecular hydrogen bonding guides a cationic amphiphilic organocatalyst to highly stereoselective aldol reactions in water
Valdivielso, ngel M.,Catot, Alba,Alfonso, Ignacio,Jimeno, Ciril
, p. 62331 - 62335 (2015/08/06)
A novel amphiphilic guanidine organocatalyst, efficient for asymmetric aldol reactions of ketones in water at neutral pH, is disclosed. The reaction presented a clear substrate dependence depicting a free energy linear correlation with ee. Intramolecular
Multifunctional "click" prolinamides: A new platform for asymmetric aldol reactions in the presence of water with catalyst recycling
Paladhi, Sushovan,Das, Joydeb,Mishra, Pratyush Kumar,Dash, Jyotirmayee
supporting information, p. 274 - 280 (2013/05/08)
"Click" chemistry is combined with organocatalysis to fabricate a multifunctional C3-symmetrical dendritic prolinamide with a hydrophobic aromatic core and hydrophilic triazolinium arms that exhibit high efficiency in catalyzing the asymmetric aldol reaction with cyclic ketones. The catalyst is water-compatible and remains active for five consecutive catalytic runs with a low catalyst loading (2 mol%), yielding the aldol products in high yields, diastereo- and enantioselectivities.
A highly efficient, large-scale, asymmetric direct aldol reaction employing simple threonine derivatives as recoverable organocatalysts in the presence of water
Wu, Chuanlong,Fu, Xiangkai,Li, Shi
experimental part, p. 1291 - 1299 (2011/04/17)
A one-step O-acylation of threonine resulted in a simple and readily available threonine-surfactant organocatalyst that could efficiently catalyze the direct asymmetric aldol reactions of cyclic and acyclic ketones with a series of aromatic aldehydes in t
New simple and recyclable O-acylation serine derivatives as highly enantioselective catalysts for the large-scale asymmetric direct aldol reactions in the presence of water
Wu, Chuanlong,Fu, Xiangkai,Li, Shi
supporting information; experimental part, p. 4283 - 4290 (2011/06/26)
New classes of O-acylation serine derived organocatalysts have been synthesized one-step by rational combination of serine with acyl chlorides at room temperature in trifluoroacetic acid. No protecting groups or chromatographic techniques are involved in
Proline-based dipeptides as efficient organocatalysts for asymmetric aldol reactions in brine
Tian, Hua,Gao, Jun-Long,Xu, Hao,Zheng, Liang-Yu,Huang, Wen-Bo,Liu, Qing-Wen,Zhang, Suo-Qin
experimental part, p. 1074 - 1080 (2011/10/02)
Simple N-proline-based dipeptides with two N-H groups in combination with 2,4-dinitrophenol (DNP) catalyze the direct asymmetric aldol reactions of aldehydes with a broad range of ketones to furnish the corresponding aldol products in high yields (up to 9
Highly efficient primary amine organocatalysts for the direct asymmetric aldol reaction in brine
Ma, Xiao,Da, Chao-Shan,Yi, Lei,Jia, Ya-Ning,Guo, Qi-Peng,Che, Li-Ping,Wu, Feng-Chun,Wang, Jun-Rui,Li, Wei-Ping
experimental part, p. 1419 - 1424 (2009/12/04)
Organocatalytic systems made up of six primary amine organocatalysts, derived from natural primary amino acids, in combination with 2,4-dinitrophenol (DNP) have proven to be efficient in the presence of brine without further addition of organic solvents. The system formed by 1f and DNP was the most efficient one; it can catalyze the direct aldol reaction with a broad range of ketones and aromatic aldehydes, giving the corresponding aldol products in high yields with up to nearly perfect diastereo- and enantioselectivities (up to 99/1 syn/anti, >99% ee).
