Article
Multidisciplinary Sciences
T. Widjaja, N. Hendrianie, S. Nurkhamidah, A. Altway, Bayu Yusuf, F. Fakhrizal, Aisyah Alifatul, Atha Pahlevi
Summary: The LASC catalyst synthesis process using iron metal (Fe) was conducted and its properties were characterized. The process includes the manufacture of the LASC Fe (DS)3 catalyst, lactic acid dehydration, polycondensation of lactic acid into L-lactic acid oligomers (OLLA), depolymerization of oligomers into L-lactide, and the ROP process to convert L-lactide into Polymers. Various analyses were performed, including Karl-Fisher; Spectroscopy Fourier Transform Infrared (FTIR); Nuclear Magnetic Resonance (HNMR); Gel Permeation Chromatography (GPC); Thermogravimetry Gravity Analysis (TGA); and X-Ray Diffraction (XRD). The use of the LASC catalyst in the form of Fe(DS)3 was found to be more effective than without using a LASC catalyst, as evidenced by higher crystallinity values and improved thermal stability.
Article
Chemistry, Multidisciplinary
Forouzan Kazemi, Louis Schutz, Jean-Yves Bergeron, Eric Gagnon, Glenn Yap, Jerome P. Claverie
Summary: Lanthanide dodecyl sulfates are highly effective catalysts for the reaction between diepoxides and diamines, a crucial step in the formation of epoxy thermosets. Among all lanthanides, the lanthanum complex LaNa(DS)(4)(H2O)(2) exhibits the highest activity, reducing the activation energy between polyethyleneimine and limonene dioxide by 60 kJ mol(-1).
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Miao Gong, Zhen Li, Mengqi Wang, Aixin Feng, Linlu Wang, Shoujun Yuan
Summary: This research investigated how different types and concentrations of Lewis acids affect gas yield and composition in supercritical water gasification of dewatered sewage sludge. AlCl3 showed the best catalytic effect, significantly increasing hydrogen and total gas yield. Adding Lewis acids improved gas yields, with AlCl3 reducing the required temperature for hydrogen generation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Multidisciplinary Sciences
Marvin L. Frisch, Sebastian Polarz
Summary: The integration of strong Lewis acids into surfactants can lead to the development of surfactants that actively reduce the size of dirt, thereby enhancing catalytic efficiency.
SCIENTIFIC REPORTS
(2021)
Article
Biochemistry & Molecular Biology
Hailong Lu, Lili Zhang, Ming Yan, Jun Ye, Kui Wang, Jianchun Jiang
Summary: The traditional strategy for isolating cellulose nanomaterials requires various chemicals and a high energy input, while achieving a low product yield owing to lignin removal during pulping and bleaching. Here, we propose a green ethanol pretreatment process with a synergistic effect using ultrasound and FeCl3 to produce lignocellulose nanofibrils (LCNF) with a high yield (over 67 %) from thermomechanical pulp. In general, FeCl3-catalyzed ethanol pretreatment can serve as a sustainable and environmentally friendly approach for converting sustainable lignocelluloses into high value-added nanomaterials. Moreover, the obtained LCNF can be applied in diverse fields.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Chemistry, Applied
Pavletta Shestakova, Margarita Popova, Agnes Szegedi, Hristina Lazarova, Thi Kim Nga Luong, Ivalina Trendafilova, Judith Mihaly, Tatjana N. Parac-Vogt
Summary: The study introduces a novel POM-functionalized hybrid catalyst immobilized on mesoporous silica, with in situ generation of active Bronsted acid sites and Lewis acidity from the metal center during synthesis. These catalysts exhibit higher catalytic activity, recyclability, and leaching resistance compared to common POM-based catalysts.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Energy & Fuels
Kai Sun, Yuewen Shao, Peng Liu, Lijun Zhang, Guoming Gao, Dehua Dong, Shu Zhang, Guangzhi Hu, Leilei Xu, Xun Hu
Summary: A solid salt catalyst FeClx-D008 was prepared by introducing FeCl3 onto a solid acidic resin D008, replacing some acid sites and improving catalytic selectivity for the production of furfural from C5 sugars.
Article
Chemistry, Multidisciplinary
Yuya Tsutsui, Daiki Tanaka, Yoshiyuki Manabe, Yuka Ikinaga, Kumpei Yano, Koichi Fukase, Akihito Konishi, Makoto Yasuda
Summary: We describe the synthesis and characterization of a photoactivated boron-based Lewis acid catalyst with a cage-shaped triphenolic ligand and three pyrenylmethyl moieties. This catalyst functions as a photoactivated Lewis acid catalyst due to the flexible three pyrenylmethyl moieties, which drive the deformation of the cage-shaped scaffold through intramolecular excimer formations of the pyrenes. Mannich-type reactions and glycosylations are significantly accelerated under 370 nm light irradiations. Notably, various glycosyl fluorides, which are not easily activated in photocatalytic systems, can be activated by the improved catalytic activity of this catalyst.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Shenghua Chen, Bingqing Wang, Jiexin Zhu, Liqiang Wang, Honghui Ou, Zedong Zhang, Xiao Liang, Lirong Zheng, Liang Zhou, Ya-Qiong Su, Dingsheng Wang, Yadong Li
Summary: A single-atomic Cu catalyst supported by Lewis acid on metal oxides was designed for efficient electrocatalytic CO2 reduction to CH4, achieving a Faradaic efficiency of 62% at -1.2 V (vs RHE) with a current density of 153.0 mA cm(-2).
Article
Chemistry, Multidisciplinary
Jun Kee Cheng, Shao-Hua Xiang, Bin Tan
Summary: Conceptually designed imidodiphosphorimidates (IDPis) are highly effective chiral acid catalysts with enzyme-like active sites and high acidity. They have a wide range of applications as Bronsted acid catalysts and precatalysts for silylium Lewis acids, enabling previously intractable carbon-carbon and carbon-heteroatom bond formation reactions with high reactivity and selectivity. The high structural confinement allows for precise control of stereo- and chemoselectivity, offering unique opportunities for controlling high-energy cation intermediates.
CHINESE JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Physical
Gareth Davies, Justin Driver, Andrew Ward, Leila Negahdar, James McGregor
Summary: New insights have been obtained into the chemical transformations occurring in the initial stages of aerosol-assisted sol-gel synthesis of catalysts through the combined application of optical trapping and Raman spectroscopy. This study represents the first operando investigation of AASG synthesis, providing direct evidence of processes within aerosols and shedding new light on the mechanistic understanding of this technology, facilitating the design of new synthetic approaches for the production of catalysts with enhanced properties.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Review
Chemistry, Multidisciplinary
Mohammad Bayat, Davood Gheidari
Summary: This statement emphasizes the importance of developing environmentally friendly catalysts, particularly Lewis acids water-stable catalysts and Lewis acid-surfactant-combined catalysts, for reactions in water.
Article
Chemistry, Physical
Malte Leverenz, Hendrik Brockmann, Andreas Dreuw, Thorsten Bach, Golo Storch
Summary: A strong enantiodivergence was observed in the oxadi-x-methane rearrangement of 2,4cyclohexadienones, ranging from +92% ee to -45% ee. The stereochemical outcome is determined solely by the oxazaborolidine substituents. The change in enantioselectivity is linked to a change in substrate binding, and TDDFT studies in the S1 excited state provided further mechanistic insights.
Article
Chemistry, Physical
Paulraj Arunkumar, Sampath Gayathri, Aruliah Rajasekar, Shanmugam Senthil Kumar, Sathish Kumar Kamaraj, Jong Hun Han
Summary: Manipulating metal valence states and porosity in metal-organic frameworks (MOFs) using alloying techniques enables the creation of high-valent metal sites and pore environments, which can enhance catalytic activity for sensing applications.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2024)
Article
Chemistry, Organic
Mingming Yang, Yingying Guo, Xue-Peng Zhang, Huaming Sun, Yanyan Wang, Weiqiang Zhang, Ya Wu, Yajun Jian, Ziwei Gao
Summary: A novel mode of IVB metal based bifunctional catalysis in Lewis acidic-Bronsted basic (LA-BB) mode has been investigated for the synthesis of 1,5-benzothiazepines, and evidence for the interaction between the two catalytic sites and substrates has been provided. The bifunctional catalyst used in this study was formed through in situ coordination between Cp2ZrCl2 and L-phenylalanine. The excellent catalytic efficiency was attributed to the coexistence of Zr (IV) center and the Bronsted basic NH2 group contained in the amino acid ligand, as demonstrated by experimental analysis and DFT studies.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Fuying Zhu, Yamei Lin
Summary: In this study, a low-metal iron-supported catalyst (Fe20/NC-Mg) was reported for the efficient synthesis of quinoxaline compounds, using water as a solvent and without additional bases. The synergistic effect of FeNx site and Mg (OH)2 nanorods in the catalyst played a key role in achieving high yields (82-91%) in 16 examples. The gram-level synthesis and reusability of the catalysts after four cycles demonstrated its industrial application potential.
Article
Chemistry, Organic
Mikhail Kozlov, Alexey Tyurin, Andrey Dmitrenok, Vyacheslav Rusak, Aleksander Fedorov, Igor Zavarzin, Yulia Volkova
Summary: This study presents a novel and practical synthesis method for phosphorus-substituted 1,3,4-thiadiazolines using phosphorylthioformic acid hydrazides and ketones. The protocol demonstrates operational simplicity, availability of reagents, and tolerance towards different functional groups.
Article
Chemistry, Organic
Jisna Jose, Thomas Mathew
Summary: 2-Cyclopentenone and its derivatives are highly esteemed synthetic intermediates with exceptional utility in organic synthesis. They are favored structural motifs in numerous pharmaceutical drugs and natural products, highlighting their significance. The review discusses the various methods used to synthesize cyclopentenones from 2016 to 2023.
