Article
Chemistry, Inorganic & Nuclear
Gholamhossein Mohammadnezhad, Ali Mohammad Amirian, Helmar Goerls, Winfried Plass, Aaron Sandleben, Sascha Schaefer, Axel Klein
Summary: The study describes the synthesis of a new Cu(I) complex and its catalytic activity, investigates the redox reaction between the ligand and Cu(II), and discusses the effect of different solvents on the reaction.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Harshita Shet, Krishna Chaitanya Gunturu, Santosh J. Gharpure, Saidurga Prasad Kommyreddy, Krishna S. Gupta, Smruti Rekha Rout, Rambabu Dandela, Anant R. Kapdi
Summary: In this study, the highly regioselective nucleophilic aromatic substitution (SNAr) of polychlorinated pyrimidines promoted by Cu(II)/PTABS is reported, aided by DFT predictions of bond dissociation energies. The unique reactivity of Cu(II)-PTABS is attributed to its coordination/activation mechanism, with further insights into the catalytic species provided.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Engineering, Environmental
Hang Xu, Erkai He, Willie J. G. M. Peijnenburg, Lan Song, Ling Zhao, Xiaoyun Xu, Xinde Cao, Hao Qiu
Summary: This study highlights the significant role of microbial EPS as reducing agents and electron transfer mediators for cupric reduction and cuprous formation in natural environments. EPS from different microbial species showed varied electron transfer ability, with c-type cytochromes playing a major role in copper transformation for Shewanella oneidensis MR-1 EPS, while functional groups like phenolic and amide dominated Cu(II) reduction for Bacillus subtilis and Saccharomyces cerevisiae EPS.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Environmental Sciences
Cheng-Feng Liang, Song-Hai Wu, Yu-Le Wang, Zhi Xu, Yong Liu, Hai-Tao Ren, Shao-Yi Jia, Xu Han
Summary: This study investigated the reactivity of the Cu(II)-S2O32- system in the reduction of Cr(VI) and the importance of the Cu(II)-Cu(I)-Cu(II) redox cycle towards environmental oxidizing contaminants.
Article
Chemistry, Organic
Hugo Minnee, Hayley Chung, Johannes Gregor Matthias Rack, Gijsbert A. van der Marel, Herman S. Overkleeft, Jeroen D. C. Codee, Ivan Ahel, Dmitri V. Filippov
Summary: This article describes the synthesis of a series of triazole-isosteres of ADP-ribosylated histidine, which serve as probes for studying ADP-ribosylating enzymes. The synthesized structures mimic N(& tau;)- and N(& pi;)-ADP-ribosylated histidine and have been evaluated for their chemical and enzymatic stability.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Kumar Kashyap Hazarika, Yusuke Yamada, Ekaterina V. Matus, Mikhail Kerzhentsev, Pankaj Bharali
Summary: The transition metal oxide based electrocatalyst with mixed valence state exhibits high activity and stability, showing promising potential for oxygen electrocatalysis.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Inorganic & Nuclear
Susmita Singh, Debasmita Paul, Tanya Nishad, Rama Ranjan Bhattacharjee, Moupiya Ghosh, Sumi Ganguly, Soumyabrata Goswami
Summary: We have synthesized a new Cu(II)-based MOF with excellent electrocatalytic behavior, which can serve as a platinum group metal-free electrocatalyst and play a vital role in fuel cells.
Article
Chemistry, Multidisciplinary
Yiqiong Zhang, Bo Zhou, Zengxi Wei, Wang Zhou, Dongdong Wang, Jing Tian, Tehua Wang, Shuangliang Zhao, Jilei Liu, Li Tao, Shuangyin Wang
Summary: This study presents a novel and efficient hydrogen production system combining glucose-assisted Cu(I)/Cu(II) redox with HER, achieving lower electricity consumption and higher production efficiency.
ADVANCED MATERIALS
(2021)
Article
Multidisciplinary Sciences
Mezna Saleh Altowyan, Eman M. M. Fathalla, Jorg H. Albering, Assem Barakat, Morsy A. M. Abu-Youssef, Saied M. M. Soliman, Ahmed M. A. Badr
Summary: Two 1D coordination polymers were synthesized by reacting 2-amino-4-picoline (2A4Pic) and quinoline-6-carboxylic acid (Qu-6-COOH) with metal (II) nitrate (M = Cd and Cu) and azide as a linker. The synthesized metal complexes [Cd(2A4Pic)(2)(N-3)(2)](n) (1) and [Cu(Qu-6-COO)(N-3)(H2O)](n) (2) showed a 1D polymeric structure. The Cd(II) in complex 1 had a slightly distorted octahedral geometry, while the Cu(II) in complex 2 had a distorted CuN2O4 octahedral geometry. Both complexes exhibited hydrogen bonding and pi-pi stacking interactions in their polymer arrays. DFT calculations showed predominantly closed-shell coordination interactions and strong compensating effects from negatively charged ligand groups.
Article
Chemistry, Multidisciplinary
Michael Okafor, Paulina Gonzalez, Pascale Ronot, Islah El Masoudi, Anne Boos, Stephane Ory, Sylvette Chasserot-Golaz, Stephane Gasman, Laurent Raibaut, Christelle Hureau, Nicolas Vitale, Peter Faller
Summary: Copper homeostasis is crucial for mammal's health and its dysregulation is implicated in diseases like Alzheimer's. In this study, a novel peptide-based copper shuttle is designed, which can selectively transport copper ions into cells and remove copper from amyloid plaques, inhibiting oxidative stress and cell toxicity. This mechanism shows potential applications in treating copper-related diseases.
Article
Chemistry, Physical
Ning Li, Gang Wu, Shibo Xi, Fengxia Wei, Ming Lin, Jinjun Qiu, Jin-Cheng Zheng, Jiabao Yi, Debbie Hwee Leng Seng, Coryl Jing Jun Lee, D. V. Maheswar Repaka, Xiaoming Liu, Zicong Marvin Wong, Qiang Zhu, Shuo-Wang Yang, He-Kuan Luo
Summary: In this article, a pair of isostructural graphene-like 2D coordination polymers (GCPs) synthesized by the coordination of benzenehexathiol (BHT) ligands with Cu(I) and Cu(II) ions, respectively, is reported. Spectroscopic characterizations indicate the coexistence of Cu(I) and Cu(II) in both GCPs with a near 1:1 ratio and a fractional oxidation state of +1.5 on average, forming a unique pair of Creutz-Taube mixed-valence 2D structures. Density functional theory calculations uncover an intramolecular pseudo-redox mechanism where the radicals on BHT ligands can oxidize Cu(I) or reduce Cu(II) ions upon coordination, leading to isostructures with distinct electron configurations. This study demonstrates for the first time that Cu(I) or Cu(II) can be used to achieve 2D isostructures, suggesting the possibility of neutral periodic structures hosting different numbers of total electrons as ground states, which may have implications for 2D materials.
Article
Chemistry, Organic
T. Moritz Weber, Joerg Pietruszka
Summary: Copper-catalyzed alkyne azide click chemistry (CuAAC) is important for drug development and biological materials labeling. A new tridentate Cu-ligand called TDETA was synthesized as a scalable and non-toxic alternative to HN3 and the previously used DTEA ligand. TDETA showed excellent solubility in organic solvents and aqueous solutions, outcompeted commercial ligands THPTA and TBTA for various azide and alkyne combinations using Cu(I) and Cu(II) species, and had a 80% recovery yield.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Zi-Qi Geng, Chunhui Zhao, Hao-Dong Qian, Si-Jia Li, Hao Peng, Hao Xu
Summary: A Cu/Ag relay catalyzed cascade reaction was used to synthesize chiral triazole-fused pyrazine scaffolds. This method utilized a novel N,N,P-ligand and showed high efficiency, functional group tolerance, excellent enantioselectivities, and a broad substrate scope using readily available starting materials.
Review
Chemistry, Physical
Songying Qu, Hao Wu, Yun Hau Ng
Summary: Hydrogen peroxide is a crucial chemical attracting attention for energy and environmental applications. The environmentally friendly solar-driven production of hydrogen peroxide, which only requires water, oxygen, and light energy, has gained the most attention. The rational design of functional photo-responsive catalysts promotes hydrogen peroxide production in photo(electro)catalytic approaches. This review systematically summarizes strategies for these catalysts and discusses prevailing hypotheses, state-of-the-art catalysts, critical challenges, and perspectives to enhance comprehension and promote interest in sustainable hydrogen peroxide production.
ADVANCED ENERGY MATERIALS
(2023)
Review
Multidisciplinary Sciences
Yaying Dou, Zhaojun Xie, Yingjin Wei, Zhangquan Peng, Zhen Zhou
Summary: This review summarizes the catalytic role of redox mediators in Li-O-2 batteries, analyzing their working principles and selection criteria, and discussing the scientific and technical challenges in designing efficient redox mediators.
NATIONAL SCIENCE REVIEW
(2022)
Article
Chemistry, Organic
Ganesh More, Pushpa Malekar, Rupali G. Kalshetti, Mahesh H. Shinde, Chepuri Ramana
Summary: This study demonstrates the Ru-catalyzed enantio- and diastereoselective dynamic kinetic resolution of alpha-(benzyloxy/benzoyloxy)acyl-gamma-butyrolactones via transfer hydrogenation. Excellent diastereo- and enantioselectivities were achieved with the in situ prepared (R,R)-Ru-FsDPEN catalyst, leading to the synthesis of important organic molecules with good efficiency.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Pawan S. Dhote, Chepuri Ramana
Summary: The [Au]-catalyzed nitroalkyne cycloisomerization process leading to anthranils may be affected by the trapping of the postulated intermediate alpha-oxo gold carbene with external nucleophiles. This study also provides evidence for the synthesis of highly functionalized indazoles through sequential bond formations.
Article
Chemistry, Organic
Sibadatta Senapati, Nivedya A. Unmesh, Manoj N. Shet, Iram Ahmad, Nandu Ajikumar, Chepuri V. Ramana
Summary: This paper describes a highly diastereoselective total synthesis of several bis-THF C-15 acetogenin natural products, as well as the synthesis of an advanced intermediate reported in the total synthesis of (E/Z)-elatenynes. Key features in the synthesis include epoxide opening, Birch reduction, Sharpless asymmetric dihydroxylation-cycloetherification, S(N)2 halogenation, and a relay cross metathesis.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Multidisciplinary
Pawan S. Dhote, Swapnil V. Halnor, Chepuri V. Ramana
Summary: The article discusses the gold-catalysed intramolecular redox cyclization of o-alkynylnitrobenzens, highlighting its importance and potential for further research in metal catalysis. It also touches upon the idea of generating alpha-oxo gold carbenes via oxygen transfer to alkynes, establishing another significant aspect in gold catalysis.
Article
Chemistry, Organic
Pawan S. Dhote, Kishor A. Pund, Chepuri Ramana
Summary: The known nitrogen-transfer reagent 1,2-benzo[d]isoxazole has been used to trap the postulated α-oxo gold carbene intermediate involved in the [Au]-catalyzed internal redox process of 2-alkynylnitrobenzenes. This process led to the development of a general convergent method for the synthesis of highly functionalized quinazoline 1-oxides.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Pawan S. Dhote, Chepuri Ramana
Summary: In this study, the possibility of interrupting the gold-catalysed intramolecular cyclization was explored in order to develop simple tools for product diversification. It was found that using 1,2-benzisoxazoles, intermolecular nitrene transfer competed with intramolecular azidoalkyne cyclization resulting in spiro indol-3-ylidene derivatives. However, when anthranil was present, both intra- and intermolecular nitrene transfer processes led to the same product indol-3-ylidene.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Pawan S. Dhote, Chepuri Ramana
Summary: The hydrazine/phenylhydrazine-mediated reductive dicarbonyl coupling reactions have been successfully carried out under mild conditions, providing polycyclic aromatic compounds and azo-substituted polyaromatic compounds with a broad substrate scope and good functional group compatibility.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Mahesh H. Shinde, Chepuri Ramana
Summary: A simple method for synthesizing pyridoindolone scaffolds with a spiroannulated tetrahydrofuran ring is described. The method involves intramolecular gold-catalyzed cycloisomerization and subsequent addition of indole C2 to the in situ generated oxocarbenium cation.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Rupali G. Kalshetti, Swapnil V. Halnor, Chepuri V. Ramana
Summary: The Rh-catalyzed cross dehydrogenative coupling (CDC)/alkylation reaction was successfully carried out under ambient conditions, selectively on the pyrazole unit while directed by the pyridine. The scope of these reactions was demonstrated by using simple and conjugated olefins for CDC and various diazo esters and the TIPS-EBX reagent for alkylation. A small molecule library based on the bis-heterocyclic core of GBT440 was developed via C-H functionalization.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Manoj N. Shet, Hemanth K. Nechooli, Chepuri V. Ramana
Summary: A simple method was developed for constructing the tetracyclic spiroketal skeleton of Lycibarbarine A and B. By coupling the fragments through epoxide opening with tetrahydroquinoline under solvent-free conditions, followed by oxidation and TBAF-mediated silyl deprotection spiroketalization, the complete tetracyclic core present in these natural products was established.
TETRAHEDRON LETTERS
(2023)
Article
Crystallography
Shaziyaparveen K. Siddiqui, C. V. Ramana, Rajesh G. Gonnade
Summary: The title compound crystallizes in monoclinic space group P2(1)/n with a planar geometry. The crystal structure is consolidated by C-H···O hydrogen bonding and a short C=O···CC (acetylene) contacts. Hirshfeld surface analysis indicates that H···H, C···H/H···C, and H···Br/Br···H interactions play a more important role in consolidating the crystal structure compared to H···O/O···H and C···C contacts.
ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Swapnil V. V. Halnor, Pawan S. S. Dhote, Chepuri V. V. Ramana
Summary: A new catalytic method has been developed to construct the quinobenzoxazine core by employing gold-catalyzed cyclization of o-azidoacetylenic ketones in the presence of anthranils. The process involves a 6-endo-dig cyclization of o-azidoacetylenic ketone catalyzed by gold, leading to the formation of an alpha-imino gold carbene, which then transfers to anthranil to form the 3-aryl-imino-quinoline-4-one intermediate. This intermediate undergoes 6 pi-electrocyclization and aromatization to form the central quinobenzoxazine core. This transformation provides a new and scalable approach to diverse quinobenzoxazine structures under mild reaction conditions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Mahesh H. Shinde, Chandrababu N. Kona, Chepuri Ramana
Summary: This study documents the gold catalysed alkynediol spiroketalization for assembling the central spiro-bis-THF fragments of symbiospirols A-C. The chiral pool approach using commercially available d-glucose and l-malic acid was employed to synthesize key building blocks. Additionally, two other possible diastereomers were synthesized to determine the relative stereochemistry of the unassigned THF-center of symbiospirols B/C.
NEW JOURNAL OF CHEMISTRY
(2022)
Review
Chemistry, Organic
Pawan S. Dhote, Pitambar Patel, Kumar Vanka, Chepuri V. Ramana
Summary: The pseudoindoxyl sub-structural motif is a unique subset of the oxygenated indole class of alkaloids, with interesting biological profiles. The challenges and future perspectives of synthesizing pseudoindoxyl compounds will be discussed based on recent developments.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Sibadatta Senapati, Chepuri Ramana
Summary: A simple approach for synthesizing the C14-C28 fragment of eribulin has been developed by utilizing one-pot gold-catalyzed alkynol cyclization/Kishi reduction and cross-metathesis/Sharpless asymmetric dihydroxylation-cycloetherification reactions. The use of easily accessible building blocks and catalytic transformations highlights the efficiency of the method in constructing the THF/THP units for eribulin synthesis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
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.