88958-64-9Relevant articles and documents
(S,S,S)-Perhydroindolic acid: efficient catalyst for direct asymmetric aldol reaction from aromatic aldehydes
Tang, Xiaoping,Liegault, Benoit,Renaud, Jean-Luc,Bruneau, Christian
, p. 2187 - 2190 (2006)
Enantioselective addition of ketones to aromatic aldehydes has been achieved with up to 88% enantiomeric excess, using the commercially available (S,S,S)-perhydroindolic acid catalyst.
Biomass waste-derived recyclable heterogeneous catalyst for aqueous aldol reaction and depolymerization of PET waste
Khiangte, Vanlalngaihawma,Laldinpuii, Z. T.,Lalhmangaihzuala, Samson,Lalmuanpuia, Chhakchhuak,Pachuau, Zodinpuia,Vanlaldinpuia, Khiangte
, p. 19542 - 19552 (2021/11/09)
In this work, we discuss the valorization of biomass waste-derived orange peel ash (OPA) by exploring its applicability as a heterogeneous catalyst in aqueous aldol reactions and demonstrating its versatility by promoting the methanolysis of poly(ethylene terephthalate) (PET) waste. The catalyst was characterized using Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis, X-ray powder diffraction (XRD), X-ray fluorescence (XRF), energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA) to decode its chemical composition. The aldol reactions were carried out at ambient temperature in the presence of water as a solvent. PET depolymerization was performed in an autoclave for 1 h using only 6% w/w OPA. The catalyst was recovered and reused in both the reactions for up to four successive cycles with minimal loss in the catalytic activity. The use of OPA as a cost-free, eco-friendly and effective recyclable catalyst enables a greener route for C-C bond formation and PET waste recycling.
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
Silica Jar-with-Lid as Chemo-Enzymatic Nano-Compartment for Enantioselective Synthesis inside Living Cells
Dubbu, Sateesh,Kim, Seonock,Kumar, Amit,Kumari, Nitee,Lee, In Su,Lim, Jongwon
supporting information, p. 16337 - 16342 (2021/06/28)
Nanodevices, harvesting the power of synthetic catalysts and enzymes to perform enantioselective synthesis inside cell, have never been reported. Here, we synthesized round bottom jar-like silica nanostructures (SiJARs) with a chemo-responsive metal-silic
Chiral imidazolium prolinate salts as efficient synzymatic organocatalysts for the asymmetric aldol reaction
Altava, Belén,Burguete, Maria Isabel,García-Verdugo, Eduardo,Luis, Santiago V.,Porcar, Raúl
supporting information, (2021/07/26)
Chiral imidazolium L-prolinate salts, providing a complex network of supramolecular interaction in a chiral environment, have been studied as synzymatic catalytic systems. They are demonstrated to be green and efficient chiral organocatalysts for direct asymmetric aldol reactions at room temperature. The corresponding aldol products were obtained with moderate to good enantioselectivities. The influence of the presence of chirality in both the imidazolium cation and the prolinate anion on the transfer of chirality from the organocatalyst to the aldol product has been studied. Moreover, interesting match/mismatch situations have been observed regarding configuration of chirality of the two components through the analysis of results for organocatalysts derived from both enantiomers of prolinate (R/S) and the trans/cis isomers for the chiral fragment of the cation. This is associated with differences in the corresponding reaction rates but also to the different tendencies for the formation of aggregates, as evidenced by nonlinear effects studies (NLE). Excellent activities, selectivities, and enantioselectivities could be achieved by an appropriate selection of the structural elements at the cation and anion.
A pH-Switchable Aqueous Organocatalysis with Amphiphilic Secondary Amine–Porphyrin Hybrids
Arlegui, Aitor,Crusats, Joaquim,Cuesta, Victor,Moyano, Albert,Torres, Pol
, (2020/07/08)
A series of amphiphilic 5-(cyclic-secondary-amine)-10,15,20-tris(4-sulfonatophenyl)porphyrins, designed with the aim of using the amphiphilic porphyrin moiety for the modulation of the aggregation state of the compound by the pH of the medium, have been synthesised, and the relationship between their supramolecular behaviour in acidic aqueous media and their organocatalytic activity in Michael and aldol reactions has been investigated. In particular, we have found that the catalytic activity of the pyrrolidine moiety in an amphiphilic isoindoline–porphyrin hybrid for the aldol reaction of cyclohexanone with 4-nitrobenzaldehyde can be selectively and reversibly switched on and off by adjusting the homogeneity of its solutions through pH variations. The catalysis of the aldol reaction by the secondary amine moiety would otherwise take place regardless of the pH of the medium. We have demonstrated that the aggregation behaviour of these amine–porphyrin hybrids can be also used for the recovery and reutilization of the catalysts.
Chiral amphiphilic secondary amine-porphyrin hybrids for aqueous organocatalysis
Arlegui, Aitor,Torres, Pol,Cuesta, Victor,Crusats, Joaquim,Moyano, Albert
, (2020/09/16)
Two chiral proline-derived amphiphilic 5-substituted-10,15,20-tris(4-sulfonatophenyl)porphyrins were prepared, and their pH-dependent supramolecular behavior was studied. In neutral aqueous solutions, the free-base form of the hybrids is highly soluble, a
Surface wettability modification of amine-functionalized polyacrylonitrile fiber to enhance heterogeneous catalytic performance for aldol reaction in water
Ma, Ning,Tao, Minli,Zhang, Chenlu,Zhang, Wenqin,Zhu, Hai
, (2020/10/08)
Heterogeneous catalytic aldol reaction has widely focused on tethering multiple functional groups upon support that can act together (for example, acid-base cooperation) to improve reaction rate beyond individual moiety alone. Here, a series of amine-func
Enhancing the selectivity of prolinamide organocatalysts using the mechanical bond in [2]rotaxanes
Calles, Mariá,Puigcerver, Julio,Alonso, Diego A.,Alajarin, Mateo,Martinez-Cuezva, Alberto,Berna, Jose
, p. 3629 - 3635 (2020/04/20)
The synthesis of a pair of switchable interlocked prolinamides and their use as organocatalysts in three different enamine-activated processes are reported. A diacylaminopyridine moiety was incorporated into the thread for directing [2]rotaxane formation further allowing the association of complementary small molecules. The rotaxane-based systems were tested as organocatalysts in asymmetric enamine-mediated processes, revealing a significantly improved catalytic ability if compared with the non-interlocked thread. The presence of an electron-withdrawing nitro group at the macrocycle helps to achieve high conversions and enantioselectivities. These systems are able to interact with N-hexylthymine as a cofactor to form supramolecular catalysts displaying a divergent catalytic behaviour. The presence or absence of the cofactor controls the chemoselectivity in competitive reactions.
Comparison of deep eutectic solvents and solvent-free reaction conditions for aldol production
Milker,P?tzold,Bloh,Holtmann
, p. 70 - 74 (2019/01/19)
In this work, we investigated the catalytic aldolase activity of the porcine pancreas lipase (PPL) for 4-nitrobenzaldehyde (4-NBA) and acetone in different deep eutectic solvent (DES) compared with bovine serum albumin (BSA)-catalyzed aldol reaction. The PPL catalyzed the aldol addition specifically towards the desired aldol product, especially in hydrophobic DES. In contrast to this result, BSA-catalyzed aldol additions did not exhibit specificity for neither aldol nor olefin formation. For the PPL-catalyzed reactions, the product composition could be directly correlated with the choice of DES, differing in their hydrophobicity. The initial reaction velocity of the aldol addition was higher in the hydrophilic DES ChCl:Gly. However, this DES was limited by the solubility for the 4-NBA substrate. The 4-NBA containing DES exhibited the highest solubility for 4-NBA. However, the fastest reaction with a final yield of 1296.5 mM, which corresponds to 71% yield and 82% conversion after 32 h, was achieved in the co-solvent acetone, making this reaction solvent-less and improving the productivity up to 40.5 mM h?1 compared to reactions performed in DES.
