2378-25-8Relevant academic research and scientific papers
Iridium and copper supported on silicon dioxide as chemoselective catalysts for dehydrogenation and borrowing hydrogen reactions
Zhu, Guanxin,Duan, Zheng-Chao,Zhu, Haiyan,Qi, Minghui,Wang, Dawei
, (2021/04/02)
High active ligand usually plays an important role during catalysis and synthesis chemistry. A new and efficient benzotriazole-pyridinyl-silane ligand (BPS) was designed, and the corresponding iridium and copper catalysts were synthesized and thoroughly characterized by means of EDS, TEM, and XPS. The resulting iridium composite revealed excellent catalytic activity for the reaction of tert-butanesulfinamide with benzyl alcohols, while copper catalyst could realize the synthesis of unsaturated carbonyl compounds through the reaction of benzyl alcohols with ketones. This provided an efficient method for selective synthesis of unsaturated carbonyl compounds from benzyl alcohols and ketones in high yields with good recovery performance.
Asymmetric Enamide–Imine Tautomerism in the Kinetic Resolution of Tertiary Alcohols
Gu, Huanchao,He, Shunlong,Rajkumar, Subramani,Tang, Mengyao,Yang, Xiaoyu
supporting information, p. 21334 - 21339 (2021/08/23)
An efficient protocol for kinetic resolution of tertiary alcohols has been developed through an unprecedented asymmetric enamide-imine tautomerism process enabled by chiral phosphoric acid catalysis. A broad range of racemic 2-arylsulfonamido tertiary allyl alcohols could be kinetically resolved with excellent kinetic resolution performances (with s-factor up to >200). This method is particularly effective for a series of 1,1-dialkyl substituted allyl alcohols, which produced chiral tertiary alcohols that would be difficult to access via other asymmetric methods. Facile and versatile transformations of the chiral α-hydroxy imine and enamide products, especially the efficient stereodivergent synthesis of all four stereoisomers of β-amino tertiary alcohols using one enantiomer of the catalyst, demonstrated the value of this kinetic resolution method.
Regioselective α-Deuteration of Michael Acceptors Mediated by Isopropylamine in D2O/AcOD
Landge, Vinod G.,Shrestha, Kendra K.,Grant, Aaron J.,Young, Michael C.
supporting information, p. 9745 - 9750 (2020/12/21)
Site-specific hydrogen/deuterium exchange is an important method to access deuterated compounds for chemical and biological studies. Herein is reported the first method for the regioselective α-deuteration of enals and enones. The transformation features D2O and AcOD as deuterium sources and amines as organocatalysts. The deuteration strategy is scalable and works on enals with a variety of substituted arene or heterocycle motifs as well as enones. The method has been applied to the synthesis of deuterated drug precursors.
Iodine-catalyzed α,β-dehydrogenation of ketones and aldehydes generating conjugated enones and enals
Cao, Yuanjie,Chen, Tieqiao,Huang, Tianzeng,Liu, Long
supporting information, p. 8697 - 8701 (2020/06/08)
A transition metal-free α,β-dehydrogenation of ketones and aldehydes was developed. This reaction was conducted in a facile I2/KI/DMSO system to produce the corresponding unsaturated compounds in good to high yields. The gram-scale experiment also indicated the potential synthetic value of this new reaction in organic synthesis. In the reaction, DMSO acted as both solvent and mild oxidant.
Hydroxyl- and Halogen-containing Chalcones for the Inhibition of LPS-stimulated ROS Production in RAW 264.7 Macrophages: Design, Synthesis and Structure–Activity Relationship Study
Shrestha, Aarajana,Shrestha, Aastha,Park, Pil-Hoon,Lee, Eung-Seok
, p. 729 - 734 (2019/07/19)
Oxidative stress due to overproduction of reactive oxygen species (ROS) plays a major role in inflammation, cancer, and neurodegenerative disorders. In this study, 60 chalcone derivatives with fluorine (F), trifluoromethyl (CF3), trifluoromethoxy (OCF3), chlorine (Cl), and bromine (Br) in ring A and with or without hydroxy (OH) in ring B were designed, synthesized, and screened for inhibitory activity against lipopolysaccharide (LPS)-stimulated ROS production in RAW 264.7 macrophages. Structure–activity relationship study revealed the importance of a hydroxyl moiety in ring B for enhancing inhibitory activity of ROS production. Furthermore, a hydroxyl group at the ortho-position is more essential for inhibition of ROS production followed by meta- and para-positions. Among all, compound 27 that contains para-chlorine moiety in ring A and ortho-hydroxy in ring B displayed the strongest inhibitory activity (IC50 = 3.42 μM) against LPS-stimulated ROS production in RAW264.7 macrophages.
Method of utilizing micro channel reactor to prepare fluorine containing chalcone derivatives
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Paragraph 0035-0036; 0041-0042, (2020/11/23)
The invention discloses a method of utilizing a micro channel reactor to prepare fluorine containing chalcone derivatives. The method comprises following steps: individually dissolving a compound represented by a formula I and a compound represented by a
Iron-oxide nanoparticles mediated cyclization of 3-(4-chlorophenyl)-1- hydrazinylisoquinoline to 1-(4,5-dihydropyrazol-1-yl)isoquinolines
Nawaz Khan,Manivel,Prabakaran,Jin, Jong Sung,Jeong, Euh Duck,Kim, Hyun Gyu,Maiyalagan
experimental part, p. 571 - 582 (2012/06/01)
Iron-oxide nanoparticles were obtained using chitosan templates and their crystalline character and particle size have been confirmed through powder x-ray diffraction and transmission electron microscopy measurements. The particle sizes were found to be 10-25 nm. The diversified chalcones 2 were reacted with 1-hydrazinylisoquinoline 1 in the presence of iron-oxide nanoparticles to the corresponding pyrazolines 3a-j in high yield and purity. The pyrazolines were characterized by spectroscopic techniques. Springer Science+Business Media B.V. 2011.
Predicting the photoinduced electron transfer thermodynamics in polyfluorinated 1,3,5-triarylpyrazolines based on multiple linear free energy relationships
Verma, Manjusha,Chaudhry, Aneese F.,Fahrni, Christoph J.
experimental part, p. 1536 - 1546 (2009/06/28)
The photophysical properties of 1,3,5-triarylpyrazolines are strongly influenced by the nature and position of substituents attached to the aryl-rings, rendering this fluorophore platform well suited for the design of fluorescent probes utilizing a photoinduced electron transfer (PET) switching mechanism. To explore the tunability of two key parameters that govern the PET thermodynamics, the excited state energy ΔE00 and the acceptor potential E(A/A-), a library of polyfluoro-substituted 1,3-diaryl-5-phenyl-pyrazolines was synthesized and characterized. The observed trends for the PET parameters were effectively captured through multiple Hammett linear free energy relationships (LFER) using a set of independent substituent constants for each of the two aryl rings. Given the lack of experimental Hammett constants for polyfluoro-substituted aromatics, theoretically derived constants based on the electrostatic potential at the nucleus (EPN) of carbon atoms were employed as quantum chemical descriptors. The performance of the LFER was evaluated with a set of compounds that were not included in the training set, yielding a mean unsigned error of 0.05 eV for the prediction of the combined PET parameters. The outlined LFER approach should be well suited for designing and optimizing the performance of cation-responsive 1,3,5-triarylpyrazolines.
