Article
Chemistry, Organic
Hongjie Gao, Jia-Yi Chen, Zhiqiang Peng, Lei Feng, Chen-Ho Tung, Wenguang Wang
Summary: Inspired by OxdA, we have developed an efficient iron catalyst that converts aldoximes to nitriles at room temperature. The catalysis involves redox activation of the N-O bond by the iron catalyst, offering a general method for the preparation of nitriles.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
San L. Pham, Taehee Kim, Frank E. McDonald
Summary: CuI and trans-N,N'-dimethylcyclohexyldiamine catalyze the single-step C-O bond cross-coupling between 1,2-di- and trisubstituted vinylic halides with functionalized alcohols, producing acyclic vinylic ethers. This method selectively gives (E)- and (Z)-vinylic ether products from the corresponding vinyl halide precursors, and is compatible with carbohydrate-derived primary and secondary alcohols and other functional groups. The conditions are mild and do not promote Claisen rearrangements.
Article
Chemistry, Organic
Zhi-Jie Niu, Lian-Hua Li, Xue-Song Li, Hong-Chao Liu, Wei-Yu Shi, Yong-Min Liang
Summary: A new transition-metal-free intermolecular Claisen rearrangement process has been developed to introduce allyl and allenyl groups into the alpha position of tertiary amides. This atom-economical process delivers alpha position-modified amides under mild conditions in moderate to good yields and showcases a broad substrate compatibility.
Article
Chemistry, Multidisciplinary
Shengbiao Yang, Chunyang Liu, Xiaoyan Shangguan, Yan Li, Qian Zhang
Summary: An unprecedented copper-catalyzed four-component reaction has been developed for the efficient synthesis of a wide range of imide derivatives.
Article
Chemistry, Applied
Dharm Dev, Tapasi Kalita, Tanmay Mondal, Bhubaneswar Mandal
Summary: This study reports a halogen-free organocatalytic Beckmann rearrangement method, which converts ketoximes to the corresponding amides/lactams. Detailed mechanistic investigation using NMR and mass spectrometry reveals that the rearrangement proceeds through two consecutive rearrangements.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Miran Lemmerer, Haoqi Zhang, Anthony J. Fernandes, Tobias Fischer, Marianne Miesskes, Yi Xiao, Nuno Maulide
Summary: Herein, we present a method for the synthesis of alpha-aryl acrylamides through polar S-to-C aryl migrations induced by a Lewis basic organocatalyst. This polar process allows subsequent elimination reactions, leading to a formal aryl/hydrogen exchange, including SO2 extrusion. The reaction is selective for electron-deficient aromatic groups and can tolerate a variety of substituents on nitrogen and in the beta-position, providing useful building blocks for further transformations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Jia-Bin Pan, Zhi-Chun Yang, Xuan-Ge Zhang, Mao-Lin Li, Qi-Lin Zhou
Summary: Here, we present a method for enantioselective phosphoric acid catalyzed amination of ketenes generated from α-aryl-α-diazoketones. Mechanistic studies elucidated the reaction pathway and explained how the catalyst expedited the transformation and controlled the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Jiwen Jiao, Xiaoming Wang
Summary: A new method has been disclosed, which combines electron-transfer-induced activation with 1,2-metalate rearrangement to efficiently convert aromatic amides into biologically relevant diarylmethylamines. This reaction, with its simplicity and versatility, shows great promise for the synthesis of amines, potentially opening up new avenues in retrosynthetic planning and finding widespread use in academia and industry.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Puneet Kumar, Vikram Singh, Jawahar L. Jat, Bhoopendra Tiwari
Summary: We have demonstrated an economical and practical approach to synthesize nitriles from easily accessible aldehydes using stable N-Boc-O-tosylhydroxylamine (TsONHBoc) as the aminating agent. This metal-free method tolerates a wide range of functional groups and provides high yields of aromatic, aliphatic, heteroarylic, and α,β-unsaturated nitriles under mild reaction conditions.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Xiangzhang Tao, Shengyang Ni, Lingyu Kong, Yi Wang, Yi Pan
Summary: A photocatalyzed 1,3-boron shift of allylboronic esters involving consecutive 1,2-boron migrations and Smiles-type rearrangement has been reported, leading to the formation of various terminally functionalized alkyl boronates. The reactions can tolerate different types of migrating variations of heteronuclei radicals and dearomatization processes, allowing for the elaboration of highly functionalized boron-containing frameworks.
Article
Chemistry, Organic
Qifa Chen, Yue Teng, Fan Xu
Summary: In this study, a lanthanide silylamide-catalyzed tandem reaction was developed for the synthesis of pyrano[2,3-b]indol-2-ones in high yields. The catalytic activity of lanthanide amides may be influenced by the cooperation of the Lewis acidity of the lanthanide center and the Bronsted basicity of the N(SiMe3)(2) anion.
Article
Chemistry, Multidisciplinary
Xinpeng Sang, Yuhao Mo, Shiya Li, Xiaohua Liu, Weidi Cao, Xiaoming Feng
Summary: A bimetallic tandem catalysis-enabled enantioselective cycloisomerization/carbonyl-ene reaction was developed, which could produce chiral 5-oxazoylmethyl & alpha;-silyl alcohols with high yield (up to 95%) and enantioselectivity (99% ee) using a broad range of N-propargylamides and acylsilanes under mild conditions. Importantly, this protocol is applicable for the late-stage modification of several bioactive molecules.
Article
Plant Sciences
Doosan Shin, Veronica C. Perez, Gabriella K. Dickinson, Haohao Zhao, Ru Dai, Breanna Tomiczek, Keun Ho Cho, Ning Zhu, Jin Koh, Alexander Grenning, Jeongim Kim
Summary: Phenylpropanoids are specialized metabolites derived from phenylalanine, and glucosinolates are defense compounds derived mainly from methionine and tryptophan. The accumulation of indole-3-acetaldoxime (IAOx), the precursor of tryptophan-derived glucosinolates, represses phenylpropanoid biosynthesis through accelerated degradation of phenylalanine ammonia lyase (PAL). This study investigates the impact of aliphatic aldoximes (AAOx) derived from methionine on phenylpropanoid production using Arabidopsis aldoxime mutants. The result shows that AAOx accumulation inhibits phenylpropanoid production and PAL activity.
Article
Chemistry, Applied
Shikharani Hazarika, Geetika Borah
Summary: The multifaceted Fe3O4-Pd@rGO nanocomposite has been successfully synthesized using biogenic method. The nanocomposite showed excellent catalytic performance in Beckmann rearrangement of aldoximes under acid-free condition.
APPLIED ORGANOMETALLIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Shuaiyu Ji, Lixing Zhao, Bingyang Miao, Meng Xue, Tao Pan, Zhichao Shao, Xin Zhou, Aiping Fu, Yuexia Zhang
Summary: In this study, we reported the electrochemical activation of nitromethane to construct isoxazoline aldoximes, using nitromethane as both the heterocyclic skeleton and oxime sources. The isoxazoline aldoximes were synthesized in a single step from low-cost nitromethane and olefins, with moderate to excellent yields. The reaction showed high atom-economy and E-selectivity. Mechanistic studies revealed that under electrochemical conditions, nitromethane could be activated to generate a 1,2,5-oxadiazole 2-oxide intermediate, which underwent [3+2] cycloaddition with olefins to yield isoxazoline aldoximes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Construction & Building Technology
Mitsuharu Sakamoto, Mengze Li, Kazuki Kuga, Kazuhide Ito, Gabriel Beko, Jonathan Williams, Pawel Wargocki
Summary: We determined the carbon dioxide emission rates from sedentary subjects using tablets or smartphones in controlled chamber exposures. The emission rates varied depending on environmental conditions and diet-induced thermogenesis. Temperature had a significant impact on emission rates, while relative humidity and ozone concentration did not. The results were similar to previously published CO2 emission rates, but further research and validation are needed.
BUILDING AND ENVIRONMENT
(2022)
Article
Engineering, Environmental
Nijing Wang, Lisa Ernle, Gabriel Beko, Pawel Wargocki, Jonathan Williams
Summary: This study continuously measured VOC emissions from human breath and skin under various conditions and found that the emissions were mainly from exhaled chemicals and VOCs resulting from skin surface lipids/ozone reactions. The data set of VOC emissions obtained from this study can be used in models to improve indoor air quality predictions.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Plant Sciences
E. Gomes Alves, T. Taylor, M. Robin, D. Pinheiro Oliveira, J. Schietti, S. Duvoisin Junior, N. Zannoni, J. Williams, C. Hartmann, J. F. C. Goncalves, J. Schongart, F. Wittmann, M. T. F. Piedade
Summary: This study investigates the variation of isoprenoid emission capacities in response to different ecological and environmental factors in the Amazonian ecosystems. The results show that the emission capacities of isoprenoids decline during the transition from wet to dry season, while emissions of heavier isoprenoids increase. The composition of emissions also shifts in response to abiotic stress and reduced photosynthetic supply of substrates for isoprenoid synthesis, indicating the plasticity of emission responses.
Article
Biochemical Research Methods
Hannah M. Britt, Tristan Cragnolini, Suniya Khatun, Abubakar Hatimy, Juliette James, Nathanael Page, Jonathan P. Williams, Christopher Hughes, Richard Denny, Konstantinos Thalassinos, Johannes P. C. Vissers
Summary: This study characterizes the acquisition methods available on an ion mobility (IM)-enabled orthogonal acceleration time-of-flight (oa-ToF) instrument for analyte semi-quantitation. The results suggest that data-independent acquisition and parallel reaction monitoring methods are the most robust for semi-quantitation in terms of achievable linear dynamic range (LDR) and lower limit of quantification (LLOQ).
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2022)
Article
Multidisciplinary Sciences
N. Wang, G. Pugliese, M. Carrito, C. Moura, P. Vasconcelos, N. Cera, M. Li, P. Nobre, J. R. Georgiadis, J. K. Schubert, J. Williams
Summary: The chemical composition of exhaled breath was examined for volatile organic compound (VOC) indicators of sexual arousal in human beings. Both genders showed decreased levels of CO2 and isoprene in the breath during sexual arousal, while some males exhibited significant increases in indole, phenol, and cresol.
SCIENTIFIC REPORTS
(2022)
Article
Environmental Sciences
Mengze Li, Gabriel Bekoe, Nora Zannoni, Giovanni Pugliese, Mariana Carrito, Nicoletta Cera, Catarina Moura, Pawel Wargocki, Priscila Vasconcelos, Pedro Nobre, Nijing Wang, Lisa Ernle, Jonathan Williams
Summary: This study investigated the importance of human metabolic emissions, finding that CO2 and CH4 emissions are influenced by factors such as temperature and individual differences under different environmental conditions. The exhaled CH4 emission rate of methane producers was significantly higher than that of non-methane producers.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Multidisciplinary Sciences
Lykourgos Bougas, Joseph Byron, Dmitry Budker, Jonathan Williams
Summary: Chiral analysis is of fundamental importance in fields such as chemistry, biology, and medicine, as well as in the development and quality control of chiral compounds in the chemical and pharmaceutical industries. The concept of absolute optical chiral analysis, enabled by cavity-enhanced polarimetry, allows for accurate and unambiguous characterization of chiral compounds in complex mixtures, even at trace levels in the gas phase. This approach and technology enable various applications, including postchromatographic analysis, rapid quality control, and in situ observation of chiral emissions.
Article
Environmental Sciences
Pascale S. J. Lakey, Andreas Zuend, Glenn C. Morrison, Thomas Berkemeier, Jake Wilson, Caleb Arata, Allen H. Goldstein, Kevin R. Wilson, Nijing Wang, Jonathan Williams, Jonathan P. D. Abbatt, Manabu Shiraiwa
Summary: Studies have shown that the reaction of squalene with ozone can produce various products, and the yield depends on relative humidity. A new mechanism has been developed to simulate these reactions and control the concentrations of different products accordingly. Increasing relative humidity significantly impacts the concentrations of various products.
ENVIRONMENTAL SCIENCE-ATMOSPHERES
(2023)
Article
Geosciences, Multidisciplinary
Mengze Li, Andrea Pozzer, Jos Lelieveld, Jonathan Williams
Summary: This study presents long-term observations of ethane, propane, and methane in the upper troposphere-lower stratosphere (UTLS) region from the IAGOS-CARIBIC project. The data reveals the growth rates of these compounds in the upper troposphere and lower stratosphere from 2006 to 2016. The findings provide valuable information for future global ethane budget estimates and the optimization of current ethane inventories.
EARTH SYSTEM SCIENCE DATA
(2022)
Article
Environmental Sciences
Therese S. Carter, Colette L. Heald, Jesse H. Kroll, Eric C. Apel, Donald Blake, Matthew Coggon, Achim Edtbauer, Georgios Gkatzelis, Rebecca S. Hornbrook, Jeff Peischl, Eva Y. Pfannerstill, Felix Piel, Nina G. Reijrink, Akima Ringsdorf, Carsten Warneke, Jonathan Williams, Armin Wisthaler, Lu Xu
Summary: This study expands the representation of fire emissions in a global chemical transport model and improves the simulation of non-methane organic gases (NMOGs) emitted by fires. The findings indicate that fire emissions contribute significantly to global atmospheric reactivity, affecting ozone and secondary particulate matter formation.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Roeder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dorich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pohlker, Bruna A. Holanda, Ovid Kruger, Ulrich Poeschl, Mira Poehlker, Patrick Joeckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, Andrea Pozzer
Summary: Reduced anthropogenic aerosol emissions during the COVID-19 pandemic had significant impacts on direct and indirect aerosol radiative forcing over Europe. The direct aerosol effect led to an increase in shortwave radiation at the surface, while the indirect effects were found to be negligible, with no significant impacts on cloud microphysics.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Correction
Ecology
Eva Y. Pfannerstill, Anke C. Noelscher, Ana M. Yanez-Serrano, Efstratios Bourtsoukidis, Stephan Kessel, Ruud H. H. Janssen, Anywhere Tsokankunku, Stefan Wolff, Matthias Soergel, Marta O. Sa, Alessandro Araujo, David Walter, Jost Lavric, Cleo Q. Dias-Junior, Juergen Kesselmeier, Jonathan Williams
FRONTIERS IN FORESTS AND GLOBAL CHANGE
(2022)
Article
Environmental Sciences
Roger Sheu, Tori Hass-Mitchell, Akima Ringsdorf, Thomas Berkemeier, Jo Machesky, Achim Edtbauer, Thomas Klupfel, Alexander Filippi, Benjamin A. Musa Bandowe, Marco Wietzoreck, Petr Kukucka, Haijie Tong, Gerhard Lammel, Ulrich Poschl, Jonathan Williams, Drew R. Gentner
Summary: Thirdhand smoke (THS), the residual smoke left in a location where smoking has occurred, can persist and expose non-smokers to harmful substances. Laboratory experiments have shown that deposited particulate matter and smoke-exposed surrogate lung lining fluid are reservoirs of gas-phase THS emissions containing hazardous air pollutants and other harmful compounds. These reservoirs can transport and emit reactive pollutants and their byproducts, increasing their overall persistence. The off-gassing of THS from deposited particulate matter and lung lining fluid can also contribute to indoor air pollution.
ENVIRONMENTAL SCIENCE-ATMOSPHERES
(2022)
Article
Environmental Sciences
Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, Akima Ringsdorf, Achim Edtbauer, Horst Fischer, Jonathan Williams, Jos Lelieveld, John N. Crowley
Summary: The reactivity of NO3 is important in modifying the fate of reactive nitrogen species at nighttime. High reactivity leads to the formation of organic nitrates and secondary organic aerosol, while low reactivity allows for heterogeneous NOx losses via N2O5 formation and uptake. This study presents measurements of NO3 reactivity and quantifies the losses of NO3 due to VOCs during a campaign in Germany. The results show variations in NO3 reactivity throughout the day and night, with monoterpenes contributing the most to the overall reactivity.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Ecology
Yanan Zhao, Dennis Booge, Christa A. Marandino, Cathleen Schlundt, Astrid Bracher, Elliot L. Atlas, Jonathan Williams, Hermann W. Bange
Summary: Our understanding of the biogeochemical cycling of dimethyl sulfide (DMS) in the Peruvian upwelling system is still limited. We conducted oceanic and atmospheric measurements of DMS in this region during two shipborne cruises in December 2012 and October 2015. DMS concentrations in surface waters were influenced by nutrient availability, and no elevated concentrations were found in the oxygen minimum zone off Peru. DMS, DMSP, and DMSO may act as radical scavengers, supported by their negative correlations with NVP ratios. Atmospheric DMS concentrations varied significantly but were primarily driven by seawater DMS. The Peruvian upwelling region was identified as a source of atmospheric DMS, but emissions were moderate compared to adjacent regions.
