Article
Chemistry, Multidisciplinary
Alexander Fanourakis, Nicholas J. Hodson, Arthur R. Lit, Robert J. Phipps
Summary: Inspired by the success of analogous substrate-directed epoxidations, an enantioselective aziridination of alkenyl alcohols has been developed. The method allows for asymmetric nitrene transfer to alkenes with varied substitution patterns. The reaction is substrate-directed and utilizes attractive non-covalent interactions between the substrate, a dianionic rhodium(II,II) tetracarboxylate dimer, and cations derived from cinchona alkaloids.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Danqing Ji, Xingwei Li
Summary: A rhodium-catalyzed C-H bond activation of propargyl carbamates with benzamides has resulted in the decarboxylative annulation, leading to the synthesis of two distinct classes of heterocycles in high efficiency and selectivity under substrate control. This protocol provides a direct synthetic method for the preparation of functionalized 1,8-naphthyridines and isoindolinones.
Article
Chemistry, Organic
Macarena Martinez-Bailen, Camilla Matassini, Francesca Clemente, Cristina Faggi, Andrea Goti, Francesca Cardona
Summary: This study presents a novel stereoselective synthetic method for pentahydroxyazepaneiminosugars. The approach involves a crucial osmium-catalyzed aminohydroxylation reaction of allylic alcohols derived from the addition of vinylmagnesium bromide to a d-mannose-derived aldehyde. This reaction forms a new C-N bond with complete regio- and stereocontrol based on the tethering approach, followed by intramolecular reductive amination to obtain the desired azepanes. This is the first application of the osmium-catalyzed tethered aminohydroxylation reaction in the synthesis of iminosugars.
Article
Chemistry, Multidisciplinary
Yuhua Liu, Difei Liu, Senyu He, Xiaofeng Huang, Feiqing Ding, Yang Zhang
Summary: The mechanism of nickel-catalyzed selective hydroalkylation of 2-aryl-1,3-dienes was investigated using DFT calculations. The rate-determining step was found to be the ligand-to-ligand hydrogen transfer (LLHT) process. The LLHT step exhibits the lowest activation barrier when hydrogen transfers to the least sterically hindered position of the diene, forming a stable allylic-Ni intermediate. The subsequent nucleophilic attack leads to regio-divergent products depending on the substrate type, with steric effects playing a role in product selectivity.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Krishna Kumar Gollapelli, Vaibhav B. Patil, Allam Vinaykumar, Rambabu Chegondi
Summary: A highly stereoselective desymmetrization reaction of 2-alkynylbenzaldehyde-tethered cyclohexadienones catalyzed by Rh(i) has been developed for the convergent construction of complex epoxy-bridged polycyclic ring systems. The process involves intramolecular Huisgen-type [3+2] cycloaddition, leading to the formation of five contiguous stereocenters with excellent exo-selectivity. Asymmetric induction is achieved for the first time in Rh(i)-catalyzed 1,3-dipolar cycloaddition using a readily accessible chiral diene as the ligand.
Article
Multidisciplinary Sciences
Liang Ling, Chenyang Hu, Linhong Long, Xue Zhang, Lixing Zhao, Liu Leo Liu, Hui Chen, Meiming Luo, Xiaoming Zeng
Summary: The hydrogenation of alkynes allows for the synthesis of olefins, which have various industrial applications. Achieving stereochemical control in this reaction has been a challenge. This study reports on a chromium-catalyzed method for selectively synthesizing E- and Z-olefins via the hydrogenation of alkynes, controlled by two carbene ligands.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Xiao-Si Hu, Jun-Xiong He, Ying Zhang, Jian Zhou, Jin-Sheng Yu
Summary: The study presents a transition metal-free highly stereoselective positional isomerization strategy using Al(OTf)(3) as a catalyst to synthesize acyclic alkenes with high stereoselectivity. Mechanistic studies reveal the formation of a carbocation intermediate with Al(OTf)(3) acting as a hidden Brønsted acid catalyst.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Organic
Tao Ye, Fangyuan Cheng, Jian Zhang, Yang-Zi Liu, Quannan Wang, Wei-Ping Deng
Summary: In this paper, a palladium-catalyzed C-H carbonylation reaction of gem-disubstituted ethylenes with phenyl formate as a convenient CO surrogate is reported. The reaction proceeds through an aryl to vinyl 1,4-palladium migration, providing a wide range of beta, beta-diaryl substituted alpha, beta-unsaturated esters with high efficiency and excellent regio- and stereoselectivities. The synthetic protocol presented in this study offers a convenient and powerful method to directly access a key intermediate for (Z)-tamoxifen.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Pradip Das, Mosidur Rahaman Molla, Amit Kumar, Rima Thakur
Summary: The study reports an efficient and stereoselective synthesis of 2,3-dideoxy-beta-O-glycosides from C3-(o-cyanobenzoate) ester protected glycal donors via Ferrier rearrangement under Pd(0)-catalyzed Tsuji-Trost conditions. The stereo-chemical outcome of the reactions was independent of the nature of protecting groups or conformational flexibility of the glycal donors. Incorporation of the directing group on the benzoate ester altered the reactivity for Tsuji-Trost as well as Ferrier Rearrangement pathway.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Chao Wu, Baode Ma, Gen-Qiang Chen, Xumu Zhang
Summary: In this study, an efficient synthetic method for chiral beta-heteroaryl amino alcohols was developed. The reaction showed high enantioselectivity and yield, and was successfully used for the gram-scale synthesis of important intermediates.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Takanobu Saito, Joaquim Caner, Naoyuki Toriumi, Nobuharu Iwasawa
Summary: A novel method for the meta-selective C-H carboxylation of 1,1-diarylethylene derivatives using a rhodium catalyst and a stoichiometric reductant has been achieved. The introduction of a carboxyl group to the aryl ring at the meta-position was enabled with high selectivity. Both experimental and computational mechanistic studies indicate that a specific rhodium migration process plays a key role in this unusual aryl-to-aryl 1,2-rhodium shift.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Shrikant M. Khake, Naoto Chatani
Summary: The Rh(III)-catalyzed reaction of aniline derivatives containing a pyrimidine directing group with vinylsilanes leads to the formation of C3-substituted indoline derivatives via a highly regioselective C-H activation/alkene cyclization cascade. Mechanistic experiments suggest that C-H bond cleavage is not the rate-determining step, but rather the reaction proceeds through the formation of a six-membered rhodacycle as a key catalytic species via pyrimidine-directed electrophilic ortho-C-H rhodation.
Article
Chemistry, Physical
Christophe M. Saudan, Aurelien Berrocosa, Julie Quintaine, Stephanie Spoehrle, Laurent Maggi, Herve Mosimann, Lionel Saudan
Summary: This paper reports a method for the regio- and chemoselective hydrogenation of conjugated dienals using a large bite-angle diphosphine and a neutral rhodium complex catalyst in the presence of a weak base. This method offers high selectivity, mild reaction conditions, and a neutral alternative to the commonly employed Claisen rearrangement for the synthesis of γ,δ-unsaturated aldehydes.
Article
Chemistry, Multidisciplinary
Lincong Sun, Haohua Chen, Bingxian Liu, Junbiao Chang, Lingheng Kong, Fen Wang, Yu Lan, Xingwei Li
Summary: This study reports the rhodium(III)-catalyzed C-H activation of anilines bearing an N-isoquinolyl directing group for oxidative [3+2] annulation with four classes of internal alkynes, leading to atroposelective indole synthesis via dynamic kinetic annulation with C-N reductive elimination constituting the stereo-determining step. The reaction proceeds under mild conditions with high regio- and enantioselectivity and functional group compatibility.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Masatoshi Yamada, Tomoaki Kato, Tomomi Ikemoto, Mitsuhisa Yamano
Summary: A highly efficient rhodium-catalyzed asymmetric hydrogenation of a sterically hindered tetrasubstituted enamine was developed, providing quick and efficient access to a key synthetic chiral intermediate in the route to an active pharmaceutical ingredient. The new rhodium catalyst showed full conversion and high enantioselectivity in the asymmetric hydrogenation of the substrate, with P-31 NMR study conducted to characterize the catalyst.
ORGANIC PROCESS RESEARCH & DEVELOPMENT
(2021)
Article
Chemistry, Physical
Anh Tuan Thanh Pham, Dung Van Hoang, Truong Huu Nguyen, Oanh Kieu Truong Le, Deniz P. Wong, Jer-Lai Kuo, Kuei-Hsien Chen, Thang Bach Phan, Vinh Cao Tran
Summary: In this study, H and Ga co-doped ZnO (HGZO) films were prepared with high transparency and low sheet resistance. Hydrogen plays a key role in enhancing transmittance and conductivity, promoting Ga3+ substitution for Zn2+ and increasing electron concentration. Furthermore, hydrogen improves crystalline grain quality and electron mobility by lowering point-defect density in HGZO films.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Dung Van Hoang, Nam Hoang Vu, Nga Thi Do, Anh Tuan Thanh Pham, Truong Huu Nguyen, Jer-Lai Kuo, Thang Bach Phan, Vinh Cao Tran
Summary: This study distinguishes the roles of hydrogen in improving electron mobility and carrier concentration in ZnO and Al doped ZnO sputtered films. The experimental and theoretical results show that hydrogen located at oxygen vacancy sites is the main factor contributing to the simultaneous increase in mobility and carrier concentration. Introducing appropriate hydrogen content during sputtering not only relaxes the crystal structure, but also supports aluminum doping, resulting in increased carrier concentration and electron mobility in the film.
JOURNAL OF MATERIOMICS
(2022)
Article
Chemistry, Multidisciplinary
Jun-Ying Feng, Qian-Rui Huang, Ha-Quyen Nguyen, Jer-Lai Kuo, Takayuki Ebata
Summary: The infrared-vacuum ultraviolet spectroscopy was used to measure the C-H stretching vibrations of pyrimidine and pyrazine, and an anharmonic analysis with evaluation of QP at DFT level was carried out to interpret the F-R mode patterns.
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Qian-Rui Huan, Yoshiyuki Matsuda, Riku Eguchi, Asuka Fujii, Jer-Lai Kuo
Summary: The vibrational spectra of methyl groups in different monomers were measured to analyze the complex features resulting from bend/umbrella-stretch Fermi resonance. CH3OH and CH3OCH3 exhibit more complex vibrational features compared to CH3SH and CH3SCH3, with multiple bands recorded and red-shifted C-H stretch fundamentals.
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Harender S. Dhattarwal, Jer-Lai Kuo, Hemant K. Kashyap
Summary: Ether-based solvents and their fluorinated derivatives have shown remarkable ability in promoting the formation of a stable solid-electrolyte interphase (SEI) layer in lithium metal batteries. Molecular dynamics simulations reveal that in the Li [FSI]-FDMB system, the dissociation of solvent molecules reduces the stability near the lithium metal anode.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Review
Biochemistry & Molecular Biology
Jake A. Tan, Jer-Lai Kuo
Summary: In this study, the structures and spectral features of protonated noble gas clusters were investigated using a first principles approach. It was found that protonated noble gas monomers and dimers have a linear structure, while the trimers can have a T-shaped or linear structure. Additionally, interesting spectral features such as progression bands and Fermi resonance interactions were observed.
Article
Chemistry, Multidisciplinary
Cheng-chau Chiu, Chung-Yu Wang, Bo-Jie Huang, Jer-Lai Kuo
Summary: We use periodic DFT calculations to study 3d transition metal dihalide monolayers in H- and T-phase. By analyzing the phonon dispersion, we identify possible stable structures and explain trends in the predicted electronic properties. Despite their simple geometric structures, the associated electronic and magnetic properties are not easily understood due to inconsistent results and differences in relative energy between electronic states.
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Pei-Kang Tsou, Hai Thi Huynh, Huu Trong Phan, Jer-Lai Kuo
Summary: Understanding the mechanism of collision-induced dissociation in mono-saccharides is challenging due to their high structural diversity. A three-step search scheme with the assistance of neural network potential was proposed to find the transition state from a large number of conformers. The scheme was applied to study the CID reactions in eight types of aldohexose pyranoses and found around 5200 transition states with a mean absolute error of energy less than 4 kJ mol(-1) using the constructed neural network potential.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Huu Trong Phan, Pei-Kang Tsou, Po-Jen Hsu, Jer-Lai Kuo
Summary: Sampling the conformational space of monosaccharides is crucial for interpreting experimental measurements, and a neural network potential (NNP) can improve the accuracy of the computational approach. By training the NNP based on density functional calculations, we obtained a better description of certain aldohexoses. An active learning scheme further enhanced the accuracy of the NNP and enabled the identification of thousands of distinct local minima.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Jun-Ying Feng, Yuan-Pern Lee, Po-Jen Hsu, Jer-Lai Kuo, Takayuki Ebata
Summary: The structures of (pyrazine)2 and (pyrazine)(benzene) hetero-dimer in a supersonic beam were investigated. The most stable structures for both dimers were identified as the cross-displaced K-K stacked structure. The analysis of the infrared spectra and quantum-chemical calculations confirmed the coexistence of multiple isomers in the supersonic jet.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Jake A. A. Tan, Rona F. Barbarona, Jer-Lai Kuo
Summary: In this study, the vibrational structure of N2H+Ng (Ng = {He, Ne, Ar, Kr, Xe, and Rn}) was investigated using reduced-dimensional calculations. It was found that the vibrational coupling in N2H+ can be controlled by tagging it with different noble gases, resulting in interesting anharmonic effects such as Fermi resonance and combination bands. The comparison of the vibrational spectra revealed a transition of .H+ from an Eigen-like to a Zundel-like state. Additionally, the binding energies for the elimination of Ng in N2H+Ng were determined.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Shweta Jindal, Po-Jen Hsu, Huu Trong Phan, Pei-Kang Tsou, Jer-Lai Kuo
Summary: This study proposes a new method that utilizes a database of stable conformers and borrows the fragmentation concept of many-body expansion (MBE) methods in ab initio methods to train a deep-learning machine learning (ML) model using SchNet. This method allows for accurate exploration of the structure and properties of molecular clusters with the accuracy of first-principles methods and the computational speed of empirical force-fields.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Hai Thi Huynh, Shang-Ting Tsai, Po-Jen Hsu, Anik Biswas, Huu Trong Phan, Jer-Lai Kuo, Chi-Kung Ni, Cheng-chau Chiu
Summary: Collision-induced dissociation tandem mass spectrometry (CID-MSn) and computational investigation were used to study the dissociation pathways of Na+-tagged fructose. Different cyclic isomers of fructose showed distinct mass spectra, indicating the ability of CID-MSn to distinguish them. Kinetic modeling helped explain previous discrepancies and confirmed the assignment of different mass spectra to fructose isomers. The model was able to reproduce most trends observed in the differences between the dissociation pathways of the cyclic fructose isomers.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Chih-Kai Lin, Jer-Lai Kuo
Summary: In this work, the vibrational spectra of ammonium, methylammonium, and dimethylammonium ions solvated by either water molecules or bisulfate anions were analyzed using anharmonic vibrational algorithms. The observed spectral features were attributed to strong Fermi resonance and combination tones. Similarities in band positions and spectral patterns between different solvation environments indicate a common vibrational coupling scheme.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Takahiro Shinkai, Po-Jen Hsu, Asuka Fujii, Jer-Lai Kuo
Summary: This study investigated the impact of fluorination on the hydrogen bond networks of protonated alkylalcohols using infrared spectroscopy and theoretical computations. The results showed that fluorination facilitated the transition of the hydrogen bond networks from linear type to cyclic type in a specific size range for protonated alkylalcohol clusters. Additionally, fluorination effectively inhibited the formation of cyclic hydrogen bond networks in protonated clusters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Organic
Faiza Diaba, Gisela Trenchs
Summary: The first violet light-mediated synthesis of gamma- and delta-lactams from N-alkenyl trichloroacetamides is reported in this paper. The reactions are conducted in tetrahydrofuran or 2-methyltetrahydrofuran as the sole solvent without catalysts or additives, under non-anhydrous conditions in an air atmosphere where the solvent serves as the radical initiator.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Feroze Hussain, Sajjad Ahmed, Ashiq Hussain Padder, Qazi Naveed Ahmed
Summary: This study reports a novel and efficient one-pot synthesis method for mixed phosphorotrithioates, which does not require supplementary additives and shows broad applicability.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Hyunjin Oh, Ikyon Kim
Summary: A new 1,2,4-triazole-pyrrolo[1,2-a]pyrazine hybrid system, 6-acylpyrrolo[1,2-a][1,2,4]triazolo[5,1-c]pyrazine, was synthesized using a catalyst-free method. This method involved sequential exposure of pyrrole-2-carbonitrile-derived substrates to DMF-DMA and acyl hydrazide, resulting in the formation of acylated pyrazine and 1,2,4-triazole rings, enabling the installation of various substituents at specific positions on the core skeleton.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Ming Yan, Si-fan Wang, Yong-po Zhang, Jin-zhong Zhao, Zhuo Tang, Guang-xun Li
Summary: Here we developed an efficient photocatalytic approach for the convenient preparation of sulfinamides. The reaction allows for the gram-scale preparation of sulfinamides and the one-pot synthesis of various sulfonyl amides.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Farzaneh Bandehali-Naeini, Zahra Tanbakouchian, Noushin Farajinia-Lehi, Nicolas Mayer, Morteza Shiri, Martin Breugst
Summary: Two tandem catalytic systems were developed for the synthesis of novel 3,4-disubstituted maleimides using the same Ugi adducts. Different maleimide structures can be synthesized using either Pd or Cu catalysis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Article
Chemistry, Organic
Tanya Raghava, Anjan Chattopadhyay, Subhadeep Banerjee, Nivedita Sarkar
Summary: Amine substitution of two ortho fluorine atoms of tetrafluoroterephthalonitrile through SNAr chemistry is easily achievable. But further fluorine substitution is only possible under forcing conditions, yielding valuable fluorophores for bioimaging.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
Review
Chemistry, Organic
Anju Chadha, Santosh Kumar Padhi, Selvaraj Stella, Sowmyalakshmi Venkataraman, Thangavelu Saravanan
Summary: Alcohol dehydrogenases are enzymes that use cofactors for oxidation or reduction reactions of alcohols or carbonyl compounds. They are utilized in green chemistry and have applications in the production of pharmaceuticals. Recombinant enzymes have solved the challenge of producing purified enzymes in large quantities. Engineered alcohol dehydrogenases have been used in asymmetric synthesis in industry. Various methods have been established for regenerating expensive cofactors to make the enzymatic process more efficient and economically viable.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2024)
