Article
Chemistry, Organic
Maciej Majdecki, Piotr Grodek, Janusz Jurczak
Summary: In this study, an enantioselective phase transfer alpha-chlorination of beta-keto esters catalyzed by hybrid amide-based Cinchona derivatives was successfully reported. The reaction showed proper quantitative yields and high asymmetric induction, with use of only 0.5 mol % hybrid catalyst based on a Cinchona core allowing for highly enantioselective chlorination with various substrates.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Kazutaka Sanada, Aoi Washio, Hiroki Ishikawa, Yasushi Yoshida, Takashi Mino, Masami Sakamoto
Summary: This article presents a method for chiral symmetry breaking of monoacylated meso diols and demonstrates its effectiveness through experiments and structural analysis. The results show that Viedma ripening can efficiently produce enantiomer crystals, achieving asymmetric expression and amplification of sugar derivatives without an external chemical chiral source. Additionally, the method is successfully applied to asymmetric desymmetrization of acyclic meso-1,2-diols.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Sai-Ya Lian, Ning Li, Yin Tian, Cheng Peng, Ming-Sheng Xie, Hai-Ming Guo
Summary: This study reports a desymmetrization reaction of meso-vic-diols with a reversal of enantioselectivity catalyzed by chiral pyridine-N-oxides with l-proline as a single source of chirality. The reaction achieved a complete and controlled switch in stereoselectivity, and chiral six-membered carbocyclic uracil nucleosides were generated with excellent enantioselectivities. Through control experiments and density functional theory calculations, it was confirmed that the reaction proceeded in a bifunctional activated manner, and the distance-directed switching of enantioselectivity played a vital role.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Organic
Maciej Majdecki, Patryk Niedbala, Agata Tyszka-Gumkowska, Janusz Jurczak
Summary: This short review focuses on asymmetric phase-transfer reactions using hybrid ammonium Cinchona catalysts with hydrogen-bond donor groups. The emphasis is on the advantages of additional functional groups present in the catalyst structure.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Organic
Yuta Chikashige, Tsunayoshi Takehara, Tsuyoshi Matsuzaki, Takeyuki Suzuki, Kenichi Murai, Mitsuhiro Arisawa, Makoto Sako
Summary: A novel chiral borinic acid (CBA) with a binaphthyl skeleton was successfully designed and synthesized. The synthesis of CBA was achieved starting from optically pure 1,1'-bi-2-naphthol and resulted in a 72% yield in four steps. The asymmetric catalytic activity of CBA was investigated in the desymmetrization of meso-1,2-diol.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Ben Liu, Yoshinao Nakagawa, Congcong Li, Mizuho Yabushita, Keiichi Tomishige
Summary: In this study, a regioselective catalyst was developed for the hydrogenolysis of 1,2-butanediol (1,2-BuD) to produce 2-butanol (2-BuOH) from biomass. The addition of iron to the catalyst improved both the activity and selectivity, and the reusability of the catalyst was enhanced through optimization of the preparation method. The catalyst showed high selectivity not only in the hydrogenolysis of 1,2-BuD, but also in the hydrogenolysis of other related alcohols.
Article
Chemistry, Organic
Yakun Wang, Shuaifei Wang, Yufeng Wu, Ting Zhao, Jie Liu, Junlin Zheng, Lin Wang, Jieli Lv, Tao Zhang
Summary: We have developed a highly efficient enantioselective fluorination reaction of 4-substituted pyrazolones using amide-based Cinchona alkaloids catalysts. The reaction affords tetrasubstituted fluorine-attached chiral center products in high yields (up to 99%) and excellent enantioselectivities (up to 98% ee). Our method features low catalyst loading, short reaction times, and wide substrate scope. Furthermore, the reaction can be carried out under sustainable conditions for 10 cycles, and the optically pure product (>99.5% ee) can be easily obtained on a multigram scale through simple extraction and recrystallization. Controlled experiments and DFT studies revealed that the multiple hydrogen bonding interactions and steric hindrance contribute to the high enantioselectivity and reactivity. This transformation provides a practical method for the preparation of chiral fluorine-containing compounds with a simple operational protocol and low catalyst loading.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Fucheng Yin, Yifan Chen, Zhongwen Luo, Shang Li, Lingyi Kong, Xiaobing Wang
Summary: This study demonstrates the application of aryl halides in organic synthesis, specifically focusing on the usage of methyl 2-bromobenzoate and 2-nitrophenyl iodides as mild and effective bromination and iodination reagents. This efficient cascade catalysis method can be applied to the total synthesis of natural products Mafaicheenamine A and Claulamine A.
Article
Chemistry, Organic
Kotaro Ikeda, Shingo Harada, Yoshinori Hashimoto, Haruka Homma, Masato Kono, Nadine Zumbraegel, Harald Groeger, Tetsuhiro Nemoto
Summary: In this study, an optically active isoquinuclidine with four chiral carbon centers was obtained using enzymatic desymmetrization. Additionally, a pentacyclic intermediate for catharanthine was synthesized in an enantioenriched form through late-stage construction of the common Iboga scaffold.
Article
Chemistry, Organic
Lotte Stockhammer, Johannes Schoergenhumer, Christopher Mairhofer, Mario Waser
Summary: This study introduces an unprecedented strategy for the asymmetric alpha-chlorination of beta-keto esters using simple Cinchona alkaloid catalysts and hypervalent iodine-based Cl-transfer reagents. The Cinchona species was found to act as a nucleophilic catalyst, generating a chiral electrophilic Cl-transfer reagent in situ, leading to good yields and enantioselectivities under operationally simple conditions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Masa Sterle, Matej Hus, Matic Lozinsek, Anamarija Zega, Andrej Emanuel Cotman
Summary: Stereopure CF3-substituted syn-1,2-diols were synthesized through the reductive dynamic kinetic resolution of corresponding alkyl ketones, yielding products with >95% ee and >87:13 syn/anti ratio. This method provides a rapid access to stereopure bioactive molecules. Moreover, DFT calculations were conducted on three types of Noyori-Ikariya ruthenium catalysts to demonstrate their general ability to control stereoselectivity through hydrogen bond acceptor SO2 region and CH/pi interactions.
Article
Chemistry, Physical
Makoto Nakatsuji, Takeshi Kubota, Morifumi Fujita, Yasuaki Okamoto, Takashi Sugimura
Summary: The use of cinchona alkaloids methyl-substituted at the 2'-position of the quinoline ring on Pd/C catalyst decreases the adsorption strength and intrinsic enantioselectivity of the modified sites, which is correlated to kinetic parameters.
Article
Chemistry, Organic
Arianna Brandolese, Mark D. Greenhalgh, Titouan Desrues, Xueyang Liu, Shen Qu, Cyril Bressy, Andrew D. Smith
Summary: This study demonstrates the sequential acylative kinetic resolution of C-2-symmetric (+/-)-1,2-syn and (+/-)-1,3-anti-diols using a packed bed microreactor loaded with HyperBTM in flow. Each substrate class showed significant differences in relative rate constants for each KR process. Optimization of the flow system allowed for isolation of reaction products in high enantiopurity and yield.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Analytical
Alessandra Recchimurzo, Fabio Maccabruni, Gloria Uccello Barretta, Federica Balzano
Summary: The hydrogen-bond accepting and enantiodiscriminating abilities of quinine were utilized to discriminate N-trifluoroacetyl derivatives of amino acids by nuclear magnetic resonance (NMR) spectroscopy. Quinine acted as both an enantiodiscriminating agent and a solubility promoter. The method achieved high-quality enantiodifferentiation and was applied to detect and quantify mixtures of amino acid derivatives using single point measurements.
Article
Chemistry, Analytical
Attila Bajtai, Istvan Ilisz, Robert Berkecz, Ferenc Fulop, Wolfgang Lindner, Antal Peter
Summary: This study investigated the diastereo- and enantioseparation of Cinchona alkaloid analogs using liquid chromatographic and subcritical fluid chromatographic modalities. The Chiralpak IC and IG columns were found to be the best in both modalities. Temperature was identified as a crucial factor in the separation process.
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
(2021)
Review
Chemistry, Multidisciplinary
Dan He, Yawen Li, Fuwen Zhao, Yuze Lin
Summary: High trap density in organic solar cells leads to localized charge carriers and reduced carrier lifetime, limiting device efficiency. This feature article summarizes the recent advances of trap suppression by material design and device engineering.
CHEMICAL COMMUNICATIONS
(2024)
Review
Chemistry, Multidisciplinary
Olivier Monfort, Arshitha Madhusudhan, Martin Motola
Summary: This article presents the advantages of coupling photocatalysis and Fenton-based processes for environmental remediation and discusses their synergy. It critically examines the simultaneous triggering of these two processes and provides insights into research approaches. The study aims to enhance understanding of this complex process and highlight the potential integration of new catalysts in current wastewater treatment technology.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Manideepa Dhar, Chittaranjan Mishra, Avijit Das, Uttam Manna
Summary: An approach of 'polymerization of monomers in its aggregated form' has been introduced to tailor the water wettability of fibrous and porous substrates, achieving hydrophobicity to superhydrophobicity transition, as well as patterned wettability. This facile chemical method provides a durable coating with adjustable and patterned wettability for various potential applications.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Saswat Ranjan Bhoi, Chhanda Debnath, Shikha Gandhi
Summary: In this article, a novel catalytic reaction using Pd(0) and Bronsted acid is reported for the synthesis of biologically important imidazolidinone-fused N-heterocycles through redox-neutral intramolecular N-allylation of indoles and pyrroles with alkynes. This atom-economical method is applicable to a wide range of substrates and eliminates the need for leaving groups or oxidizing agents commonly used in traditional allylation reactions.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Longkun Chen, Mingshuai Zhang, Meichen Liu, Zhuoyuan Liu, Yuetong Qiu, Zhilai Zhang, Fuchao Yu, Jiuzhong Huang
Summary: In this study, an efficient Rh(III)-catalyzed selective mono- and dual-C-H bond functionalization/cyclization with iodonium ylide as the sole coupling partner was demonstrated. Fused benzodiazepine skeletons were obtained in excellent yields, providing an improved approach to dual C-H unsymmetrical functionalization.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Alice Kennett, Sven Epple, Gabriella van der Valk, Irene Georgiou, Evelyne Gout, Romain R. Vives, Angela J. Russell
Summary: This study presents the design and synthesis of sulfated disaccharide inhibitors based on IdoA(2S)-GlcNS(6S), which showed potent inhibition of Sulf-2. The results suggest that IdoA(2S)-GlcNS(6S) is the shortest fragment size required for effective inhibition of Sulfs, and a trisulfated disaccharide is identified as the minimal fragment size of heparan sulfate for effective endosulfatase inhibition.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Mauro Garbini, Andrea Brunetti, Riccardo Pedrazzani, Magda Monari, Massimo Marcaccio, Giulio Bertuzzi, Marco Bandini
Summary: The self-adaptability of galvanostatic electrolysis was found to be helpful in a multistage chemo- and diastereoselective electrochemically promoted cyclodimerization of chalcones. Through a series of reductive events, densely functionalized cyclopentanes with five contiguous stereocenters were obtained (25 examples, yields up to 95%, dr values up to >20:1). Further experimental and electrochemical investigations indicated the crucial role of dynamic kinetic resolution of the aldol intermediate in the reaction mechanism.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Dhananjay S. Nipate, Neha Meena, Prakash N. Swami, Krishnan Rangan, Anil Kumar
Summary: In this study, the synthesis of functionalized benzo[a]phenazines and indazolo[2,3-a]quinolines was achieved through Rh(III)-catalyzed oxidative annulation of 2-arylquinoxalines and 2-aryl-2H-indazoles with allyl alcohols. The method showed a wide substrate scope, excellent functional group tolerance, good to high yields of annulated products, and the capability for scaled-up synthesis. A tentative mechanism of the annulation reaction was proposed based on a preliminary mechanistic investigation.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Ruonan Zhang, Abudukadi Tudi, Xia Yang, Xuping Wang, Zhihua Yang, Shujuan Han, Shilie Pan
Summary: A new lead tellurium borate material with a unique fundamental building block [B4O10] was synthesized and found to exhibit high birefringence. The structure-property relationship was discussed using first-principles calculations.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Amresh Kumar Singh, Baishali Thakurta, Anupam Giri, Monalisa Pal
Summary: This study introduces three key concepts for the quick synthesis of large-scale high-quality 2D materials films and their utilization in device fabrication.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Reina Hagiwara, Shun Nishimura, Kosuke Okeyoshi
Summary: A copolymer-conjugated nanocatalytic system has been developed to improve electron transfer and enhance photoinduced H2 generation.
CHEMICAL COMMUNICATIONS
(2024)