159208-44-3Relevant academic research and scientific papers
A Versatile Metalloporphyrinic Framework Platform for Highly Efficient Bioinspired, Photo- and Asymmetric Catalysis
He, Wei-Long,Zhao, Min,Wu, Chuan-De
, p. 168 - 172 (2019)
Even though numerous bioinspired catalysts have been developed, there remain huge gaps between the artificial and natural catalysts, because it is very difficult to imitate simultaneously the complicated constituents, structures, and synergistic effect of enzymes. We report herein a versatile metalloporphyrinic framework platform, which exhibits high efficiency in bioinspired catalysis, photocatalysis, and asymmetric catalysis. The catalytic properties are highly dependent on the tunable constituents and their cooperation, and are significantly superior to the corresponding molecular catalyst systems which lack the synergistic effects. Since there are numerous functional moieties that can readily be incorporated into the metalloporphyrinic framework platform, a myriad of applications can be simply realized by embedding different functional moieties.
Homochiral bifunctional L-prolinamide- and L-bis-prolinamide-catalyzed asymmetric aldol reactions performed in wet solvent-free conditions
Anaya de Parrodi, Cecilia,Domínguez-Huerta, Alejandra,Hernández Pérez, Julio M.,Huelgas, Gabriela,Rojas Cabrera, Haydee,Sabala, Rocío,Somanathan, Ratnasamy,de la Higuera Macías, Maximiliano
supporting information, p. 22 - 36 (2020/12/04)
In this study, the novel bifunctional homochiral thiourea-L-prolinamides 1–4, tertiary amino-L-prolinamide 5, and bis-L-prolinamides 6 and 7 were prepared from enantiomerically pure (11R,12R)-11,12-diamino-9,10-dihydro-9,10-ethanoanthracene 8 and (11S,12S
Proline-Histidine Dipeptide: A Suitable Template for Generating Ion-Tagged Organocatalysts for the Asymmetric Aldol Reaction
Inani, Heena,Singh, Avtar,Bhati, Meeta,Kumari, Kiran,Kucherenko, Alexander S.,Zlotin, Sergei G.,Easwar, Srinivasan
, p. 2702 - 2712 (2021/06/02)
Proline-histidine dipeptide laid the foundation for the construction of three new ion-tagged organocatalysts, utilising the imidazole moiety of histidine for generating the quaternary species. A brief comparative investigation of the catalysts in the enam
New small γ-turn type: N -primary amino terminal tripeptide organocatalyst for solvent-free asymmetric aldol reaction of various ketones with aldehydes
Begum, Zubeda,Kwon, Eunsang,Nakano, Hiroto,Okuyama, Yuko,Seki, Chigusa,Takeshita, Mitsuhiro,Thiyagarajan, Rajkumar,Tokiwa, Michio,Tokiwa, Suguru,Uwai, Koji
, p. 38925 - 38932 (2021/12/20)
New small γ-turn type N-primary amino terminal tripeptides were synthesized and their functionality as an organocatalyst was examined in the asymmetric aldol reaction of various ketones with different aromatic aldehydes under solvent-free neat conditions to afford the desired chiral anti-aldol products in good to excellent chemical yields, diastereoselectivities and enantioselectivities (up to 99%, up to syn?:?anti/13?:?87 dr, up to 99% ee). This journal is
“Ship-in-a-Bottle” Strategy for Immobilization of 9-Amino(9-deoxy)epi-Cinchona Alkaloid into Molecularly Imprinted Solid Acid: Acetal Hydrolysis/Asymmetric Aldol Tandem Reaction
Wei, Shuai,Zhang, Jianing,Li, Shan,Ma, Xuebing
, p. 627 - 636 (2020/12/09)
Direct immobilization of versatile 9-amino(9-deoxy)epi-cinchona alkaloids without molecule modification to achieve heterogeneous organocatalysis is of interest in the low-cost production of optically active compounds. In this paper, an exquisite “ship-in-a-bottle” strategy for direct and simple immobilization of 9-amino-(9-deoxy)epi-quinine (QNNH2) into hollow polystyrene nano-bowl with imprinted free space around ?SO3H was developed via acid-base reaction and radical polymerization. The heterogeneous organocatalyst with 0.44 mmol g?1 of QNNH2 and 0.48 mmol g?1 of residual ?SO3H possessed fast mass transfer due to the characteristic architectural features, such as thin shell thickness, free space around catalytic site, and hollow interior. In heterogeneous acetal hydrolysis/asymmetric aldol tandem reaction, good to excellent catalytic performances (90–95 % yields, anti/syn=88/12–96/4, and 97–99 % ee anti) for acetals bearing electron-withdrawing substituents (R=o, m, p-NO2, Cl) were achieved. The “ship-in-a-bottle” QNNH2 displayed good stability and reusability with excellent catalytic performances in the reuses.
Pro-phe derivatives as organocatalysts in asymmetric aldol reaction
Aydogan, Feray,Karaoglu, Merve,Yolacan, Cigdem
supporting information, p. 233 - 239 (2021/03/19)
The aldol reaction which is the most important one among the C-C bond forming reactions, is widely used by synthetic organic chemists to obtain β-hydroxycarbonyl compounds which are important starting components for biologically active compounds in optica
L-proline/cholesterol and diosgenin based thiourea cooperative system for the direct asymmetric aldol reaction in the presence of water
Eymur, Serkan,Ta?ci, Enis,Uyanik, Arzu,Yilmaz, Mustafa
, p. 1278 - 1284 (2020/11/20)
A series of cholesterol and based hydrophobic urea and thiourea compounds were synthesized and successfully used as a cocatalyst for L-proline catalyzed aldol reactions in the presence of water. The anticonfigured products were obtained with good yields (up to 94%), high diastereoselectivities (up to 95:5), and high enantiomeric excesses (up to 93% ee). The successful results for catalytic efficiency of L-proline in the presence of water reveal the importance of the hydrophobic nature of cholesterol and diosgenin parts of thiourea on the reactivity and selectivity in the presence of water.
Chiral proline sulfonamide bifunctional catalyst and preparation method and application thereof
-
Paragraph 0097-0100, (2020/08/17)
The invention discloses a novel chiral sulfonamide bifunctional catalyst and a preparation method and application thereof. The catalyst comprises a compound A or a compound B. The molecular structureof the compound A is shown as a formula (I) which is des
Design and preparation of a novel prolinamide-based organocatalyst for the solvent-free asymmetric aldol reaction
Martins, Rafaela de S.,Pereira, Mathias P.,de Castro, Pedro P.,Bombonato, Fernanda I.
, (2019/12/24)
The preparation of four novel organocatalysts as highly diastereo and enantioselective catalysts for the solvent-free asymmetric aldol reaction was described. These organocatalysts were synthesized in eight steps applying simple and commercially available starting materials. The best results were obtained for the proline-derived catalyst, providing access to the desired adducts in up to 95% yield, 1:19 syn/anti and 98% e.e. Moreover, even sterically bulky aldehydes and substituted cyclohexanones were well tolerated. DFT calculations and control experiments indicated that several hydrogen bonding interactions between the aldehyde and the enamine intermediate are responsible for the stereoselective chiral induction process and that the trifluoroacetate counter-anion is crucial for the attainment of higher stereoselectivities.
Evaluation of Amino Nitriles and an Amino Imidate as Organo?-catalysts in Aldol Reactions
Brown, Alexander J.,Clarke, Paul A.,Vagkidis, Nikolaos
supporting information, p. 4106 - 4112 (2019/10/28)
The efficiency of l -valine and l -proline nitriles and a tert -butyl?- l -proline imidate as organocatalysts for the aldol reaction have been evaluated. l -Valine nitrile was found to be a syn -selective catalyst, while l -proline nitrile was found to be anti -selective, and gave products in modest to good enantioselectivities. tert -Butyl l -proline imidate was found to be a very efficient catalyst in terms of conversion of starting reagents to products, and gave good anti -selectivity. The enantioselectivity of the tert -butyl l -proline imidate was found to be good to excellent, with products being formed in up to 94percent enantiomeric excess.
