Most Popular 2018 – 2019 Chemical Science Articles By Subject

The ongoing COVID-19 pandemic has had wide reaching implications on the global research community. In addition to limitations on the ability to conduct research, many in our community are experiencing restricted or no access to institutional resources and published research articles. In-line with our continuing efforts to support the chemical sciences community, we have put together some subject-specific collections of our most popular Chemical Science content from 2018 and 2019. These specially curated collections are designed to highlight some of the exceptional research published in Chemical Science – and like all Chemical Science articles, they are free to access and read from anywhere on the globe with no restrictions. We hope you will find them useful during this time.

Many of the articles selected in the collections below are also included in our 20182019 and 2020 ChemSci Pick of the Week Collections, as well as our 20182019 and 2020 Chemical Science HOT Article Collections.

 

Organic chemistry

This collection presents some outstanding contributions to the field, ranging from dual vicinal functionalisation of heterocycles via an interrupted Pummerer coupling/[3,3]-sigmatropic rearrangement cascade to a review of C4-H indole functionalisation. Browse the full collection

 

Catalysis Chemistry

This specially curated collection pulls together some of the most popular articles from 2018 and 2019 in the field of catalysis. Articles range from Pd doped with Te for the highly selective electrocatalytic reduction of aqueous CO2 to a review of catalyst characterization in the presence of solvent through liquid phase structure-activity relationships.
Browse the full collection

 

Analytical chemistry

This collection ranges from high throughput reaction screening using desorption electrospray ionization mass spectrometry to a review of fluorescent probes for organelle-targeted bioactive species imaging.
Browse the full collection

 

Materials chemistry

This collection presents some outstanding contributions to the field, ranging from the rational design of a water-soluble NIR AIEgen to a review of the mechanical properties of metal-organic frameworks.
Browse the full collection

 

Main group, inorganic & organometallic chemistry

This collection presents articles ranging from the reactivity of diborane(4) towards pyridine and isocyanide to a review of spin states, vibrations and spin relaxation in molecular nanomagnets and spin qubits.
Browse the full collection

 

Chemical biology

This collection includes articles ranging from dual-biomarker-triggered fluorescence probes for differentiating cancer cells to a review of the biomedical applications of copper-free click chemistry.
Browse the full collection

 

Physical & theoretical chemistry

This collection presents some outstanding contributions to the field, ranging from a study that asks why are photosynthetic reaction centres dimeric to a review of polariton chemistry.
Browse the full collection

 

Supramolecular chemistry

This collection presents some outstanding contributions to the field, ranging from a halogen-bond assembled supramolecular catalyst, XBphos-Rh, to a review of electrochemically switchable rotaxanes.
Browse the full collection

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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How to Identify Diverse Acids with High-Throughput Research

Have you ever heard of nonulosonic acids? As a materials chemist I hadn’t, as most of the acids I’ve dealt with are either acting as ligands or inorganic and I tend to forget that sugars are actually acids. These nine-carbon sugars are critical for a wide range of cellular functions throughout living organisms. Over 100 different members of this broad group of acids have been identified, all of which can undergo diversification at multiple positions, generating an even larger library of derivatives. What types of modifications can occur has yet to be fully realized, as novel compounds are continually discovered, particularly in prokaryotes. Even when examining a limited number of modifications, say 15, the number of possible derivatives is staggering, reaching several thousand without stereochemical considerations. Identifying these acids is key, as they have been linked to virulence in pathogenic bacteria and their previously mentioned diversity makes them challenging to genomically analyze.

Given these challenges, current detection practices rely on staining and fluorescent labeling which can be labor intensive and specific to a small number of acids. Early approaches based on mass spectroscopy were limited due to the complex backgrounds produced and the difficulties separating signal and noise. However, developments in high-resolution spectrometers and increased data processing abilities have led to successful analysis of increasing numbers of known metabolites. Researchers in the Netherlands and Russia extended this work to develop a screening approach to identify a diverse range of nonulosonic acids via small mass channel mass spectroscopy from previously unexplored environmental microbes (Figure 1).

Figure 1. Outline of the general procedure for the survey pipeline, beginning from the cells to the final structural analysis of the identified acids.

To successfully identify these unknown derivatives, the researchers identified specific ulosonic acid fragments invariant to functionalization. They used 1,2-diamino-4,5-methylene dioxybenzene, an alpha-keto-acid specific labeling reagent, to shift the double bond equivalents from the general cellular background and help conserve the core ulosonic acid structure. By screening a known range of acids with different functional group moieties, they were able to identify universal features for this category of molecules (Figure 2). From there, they created a full process for rapid-throughput studies that automated everything from initial identification of a potential acid molecule through filtering and structural analysis.

Figure 2. A) Universal fragmentation route used to identify nonulasonic acids in the screening, B) data output of various ulosonic acid derivatives identified in the study, and C) differences seen from the chemical labeling introduced in the procedure.

After the pipeline was established, the researchers used various standard cell lines, plant, animal, and algal, for a molecular level survey to confirm the validity of their approach for full-cell analysis. In general, the plants and yeast cells contained no nonulosonic acids, as expected, while the microalgae and animal cells had a range of different nonulosonic acids present. As these acids are thought to play a role in bacterial virulence, a bacteria known to display the acids was screened and several subtypes of animal and bacterial acids were identified as incorporated into the cells. With that validation, the researchers moved on to a wide range of non-pathogenic bacteria. They discovered that over half of these bacteria possess nonulosonic acids; in fact, some have only slightly lower acid abundance than mammalian cells. While much of this data was obtained from single cultures, it represents exciting validation of a broad new approach that could be used to identify potential targets for medical applications and continue to extend our understanding of the diversity of nonulosonic acids.

To find out more, please read:

Tackling the chemical diversity of microbial nonulosonic acids – a universal large-scale survey approach

Hugo B. C. Kleikamp, Yue Mei Lin, Duncan G. G. McMillan, Jeanine S. Geelhoed, Suzanne N. H. Naus-Wiezer, Peter van Baarlen, Chinmoy Saha, Rogier Louwen, Dimitry Y. Sorokin, Mark C. M. van Loosdrecht and Martin Pabst

Chem. Sci., 2020, 11, 3074-3080.

About the blogger:

Dr. Beth Mundy is a recent PhD in chemistry from the Cossairt lab at the University of Washington in Seattle, Washington. Her research focused on developing new and better ways to synthesize nanomaterials for energy applications. She is often spotted knitting in seminars or with her nose in a good book. You can find her on Twitter at @BethMundySci.

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Seeing is Believing: Is Your Polymerization Working?

If you are a polymer chemist, you may have dreamt of having a pair of eyes that can directly tell whether your polymerization reaction is working or not. Good news! Randall H. Goldsmith of the University of Wisconsin-Madison, U.S. and coworkers have developed an optical technique to monitor the course of a polymerization reaction in real-time. This breakthrough has been published in Chemical Science (DOI: 10.1039/C9SC05559B).

This technique relies on two parameters, fluorescence polarization anisotropy and aggregation-induced emission, to examine molecular weights. The authors specifically studied a well-controlled polymerization of norbornene (NB) into polynorbornene. Besides monomer, they added small amounts of two fluorescent probes, perylene diimide-functionalized norbornene (PDI-NB) and tetraphenylethylene-linked norbornene (TPE-NB), to the polymerization system. These NB derivatives were co-polymerized with NB (Fig.1).

Figure 1. Polymerization of norbornene (NB) catalyzed by a ruthenium-based Grubbs Generation II catalyst (Grubbs Gen II). PDI-NB and TPE-NB are two probes co-polymerized with NB to monitor the growth of polynorbornene.

The technique temporally resolved the evolution of polynorbornene molecular weight. The polymerization incorporated the probe molecules into the backbones of polynorbornene. As polymer chains grew, the rotational freedom of PDI-NB became increasingly limited, giving rise to an enhanced anisotropy signal during the first 200 min of polymerization (Fig. 2a, top panel and Fig. 2b, red curve). Further polymerization brought the incorporated TPE-NB together, triggering the aggregation-induced fluorescence emission of TPE-NB (Fig. 2a, bottom panel and Fig. 2b, blue curve). Importantly, the rise of the emission intensity from TPE-NB immediately followed the saturation of anisotropy signal from PDI-NB, making the two molecules complementary for monitoring the polymer growth in different time scales. Critically, the anisotropy signal intensity of PDI-NB correlated positively with the weight-average molecular weight of polynorbornene (Fig. 2c), demonstrating the capability of this technique to track the progression of polymer growth.

Figure 2. (a) (top) Color-scale images of anisotropy values of PDI-NB and (bottom) emission intensities of TPE-NB over time. Dots are top-view toluene microdroplets where polymerization happens. Scale bar: 250 µm. (b) Time-evolution of average anisotropy values of PDI-NB (red) and aggregation-induced-emission (AIE) intensity of TPE-NB (blue) throughout a polymerization. (c) The correlation between measured anisotropy values and the weight-average molecular weights of polynorbornene. The red dashed line provides a visualization of the trend.

The reported technique is applicable to other ring-opening metathesis polymerizations (ROMPs) involving monomers such as norbornadiene.

 

For expanded understanding, please read:

Optical Monitoring of Polymerizations in Droplets with High Temporal Dynamic Range

Andrew C. Cavell, Veronica K. Krasecki, Guoping Li, Abhishek Sharma, Hao Sun, Matthew P. Thompson, Christopher J. Forman, Si Yue Guo, Riley J. Hickman, Katherine A. Parrish, Alán Aspuru-Guzik, Leroy Cronin, Nathan C. Gianneschi, and Randall H. Goldsmith

Chem. Sci., 2020, 11, 2647-2656.

 

The blogger acknowledges Zac Croft at Virginia Tech, U.S., for his careful proofreading of this post.

 

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Chemistry from the University of California, Santa Cruz, in the United States. He is passionate about the communication of scientific endeavors to both the general public and other scientists with diverse research expertise to introduce cutting-edge research to broad audiences. He is a blog writer for Chem. Comm. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

 

 

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Chemical Science 2019 Outstanding Reviewers

We are delighted to highlight the Outstanding Reviewers for Chemical Science in 2019, as selected by the editorial team, for their significant contribution to the journal. The reviewers have been chosen based on the quantity, quality and timeliness of the reports completed over the last 12 months.

We would like to say a big thank you to those individuals listed here as well as to all of the reviewers that have supported the journal.

Each Outstanding Reviewer will receive a certificate to give recognition for their significant contribution.

Dr Igor Alabugin, Florida State University, ORCiD: 0000-0001-9289-3819
Dr Gonçalo Bernardes, University of Cambridge, ORCiD: 0000-0001-6594-8917
Dr Luca Bernardi, University of Bologna, ORCiD: 0000-0002-7840-3200
Dr Davide Bonifazi, Cardiff University, ORCiD: 0000-0001-5717-0121
Professor M. Kevin Brown, Indiana University, ORCiD: 0000-0002-4993-0917
Professor Tianning Diao, New York University, ORCiD: 0000-0003-3916-8372
Professor Dr Matthias Drieß, Technical University Berlin, ORCiD: 0000-0002-9873-4103
Professor Xinliang Feng, TU Dresden, ORCiD: 0000-0003-3885-2703
Professor Dr Frank Glorius, WWU Münster, ORCiD: 0000-0002-0648-956X
Professor Hiroshi Kitagawa, Kyoto University, ORCiD: 0000-0001-6955-3015
Professor Dr Paul Knochel, Ludwig-Maximilians-Universität München, ORCiD: 0000-0001-7913-4332
Dr Sami Lakhdar, LCMT, ENSICAEN, CNRS, ORCiD: 0000-0002-1168-7472
Professor Jinghong Li, Tsinghua University, ORCiD: 0000-0002-0750-7352
Professor Stephen Liddle, The University of Manchester, ORCiD: 0000-0001-9911-8778
Professor Stefan Matile, University of Geneva, ORCiD: 0000-0002-8537-8349
Professor Dr Kilian Muniz, ICIQ, ORCiD: 000-0002-8109-1762
Dr Manuel Nappi, University of Cambridge, ORCiD: 0000-0002-3023-0574
Professor Dr Martin Oestreich, Technical University Berlin, ORCiD: 0000-0002-1487-9218
Professor Dr Andreas Schnepf, Universität Tübingen, ORCiD: 0000-0002-7719-7476
Professor Dr Armido Studer, WWU Münster, ORCiD: 0000-0002-1706-513X
Professor Bo Tang, Shandong Normal University, ORCiD: 0000-0002-8712-7025
Professor Tomás Torres, Universidad Autonoma de Madrid, ORCiD: 0000-0001-9335-6935
Professor Christopher Uyeda, Purdue University, ORCiD: 0000-0001-9396-915X
Dr Jan van Hest, Technische Universiteit Eindhoven, ORCiD: 0000-0001-7973-2404
Professor Bo Wang, Beijing Institute of Technology, ORCiD: 0000-0001-9092-3252
Professor Andrew Wilson, University of Leeds, ORCiD: 0000-0001-9852-6366
Professor Dr Wen-Jing Xiao, Central China Normal University, ORCiD: 0000-0002-9318-6021
Professor Vivian Yam, The University of Hong Kong, ORCiD: 0000-0001-8349-4429
Professor Juyoung Yoon, Ewha Womans University, ORCiD: 0000-0002-1728-3970
Professor Shu-Li You, Shanghai Institute of Organic Chemistry, ORCiD: 000-0003-4586-8359

 

We would also like to thank the Chemical Science board and our community for their continued support of the journal, as authors, reviewers and readers.

If you would like to become a reviewer for our journal, just email us with details of your research interests and an up-to-date CV or résumé.  You can find more details in our author and reviewer resource centre.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

Chemical Science, Royal Society of Chemistry

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HOT articles: February

We are pleased to share a selection of our referee-recommended HOT articles for January. We hope you enjoy reading these articles and congratulations to all the authors whose articles are featured! As always, Chemical Science is free to read & download. You can find our full 2020 HOT article collection here.

 

Metal complexes as a promising source for new antibiotics
Angelo Frei, Johannes Zuegg, Alysha G. Elliott, Murray Baker, Stefan Braese, Christopher Brown, Feng Chen, Christopher G. Dowson, Gilles Dujardin, Nicole Jung, A. Paden King, Ahmed M. Mansour, Massimiliano Massi, John Moat, Heba A. Mohamed, Anna K. Renfrew, Peter J. Rutledge, Peter J. Sadler, Matthew H. Todd, Charlotte E. Willans, Justin J. Wilson, Matthew A. Cooper and Mark A. T. Blaskovich
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06460E
10.1039/C9SC06460E

 

 

A clustering-triggered emission strategy for tunable multicolor persistent phosphorescence
Qing Zhou, Tianjia Yang, Zihao Zhong, Fahmeeda Kausar, Ziyi Wang, Yongming Zhang and Wang Zhang Yuan
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06518K

10.1039/C9SC06518K

 

 

Time-resolved luminescence detection of peroxynitrite using a reactivity-based lanthanide probe
Colum Breen, Robert Pal, Mark R. J. Elsegood, Simon J. Teat, Felipe Iza, Kristian Wende, Benjamin R. Buckley and Stephen J. Butler
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06053G
10.1039/C9SC06053G

 

Electron-enriched thione enables strong Pb–S interaction for stabilizing high quality CsPbI3 perovskite films with low-temperature processing
Xiaojia Xu, Hao Zhang, Erpeng Li, Pengbin Ru, Han Chen, Zhenhua Chen, Yongzhen Wu, He Tiana and Wei-Hong Zhu
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06574A
10.1039/C9SC06574A

 

Accurate chiral pattern recognition for amines from just a single chemosensor
Yui Sasaki, Soya Kojima, Vahid Hamedpour, Riku Kubota, Shin-ya Takizawa, Isao Yoshikawa, Hirohiko Houjou, Yuji Kubo and Tsuyoshi Minami
Chem. Sci., 2020, Advance Article
DOI: 10.1039/D0SC00194E

10.1039/D0SC00194E

 

Tackling the chemical diversity of microbial nonulosonic acids – a universal large-scale survey approach
Hugo B. C. Kleikamp, Yue Mei Lin, Duncan G. G. McMillan, Jeanine S. Geelhoed, Suzanne N. H. Naus-Wiezer, Peter van Baarlen, Chinmoy Saha, Rogier Louwen, Dimitry Y. Sorokin, Mark C. M. van Loosdrecht and Martin Pabst
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06406K

10.1039/C9SC06406K

 

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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The 19th International Symposium on Silicon Chemistry (ISOS XIX), Toulouse, July 2020

ISOS XIX Royal Society of Chemistry

 

Chemical Science is pleased to be sponsoring The 19th International Symposium on Silicon Chemistry (ISOS XIX) in Toulouse, 05 – 10 July 2020 along with RSC Advances, ChemComm and Dalton Transactions.

It will be held at the University Paul Sabatier and aims to bring together outstanding scientists from both academia and industry to explore the frontiers of Silicon Chemistry from basic and fundamental science to the development of new synthetic tools and of silicon-based materials and technologies. The scientific programme will reflect the latest achievements in synthesis (organic and organometallic), bio-organo silicon chemistry, catalysis, and material sciences (including bio-composites, silica, silsesquioxanes, silicones, silicon polymers etc..).

You can find out more on the website.

Don’t forget to register before the deadline:

Early Bird Registration Deadline:  15 April 2020

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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F. Albert Cotton Award in Synthetic Inorganic Chemistry, Spring ACS National Meeting, March 22 – 26 | Philadelphia

Chemical Science and Dalton Transactions are very pleased to be sponsoring the F. Albert Cotton Award in Synthetic Inorganic Chemistry Symposium this year as part of the Spring ACS National Meeting in Philadelphia. The award recognizes outstanding synthetic accomplishment in the field of inorganic chemistry. The award is granted regardless of race, gender, age, religion, ethnicity, nationality, sexual orientation, gender expression, gender identity, presence of disabilities, and educational background. Creativity and imagination is especially valued.

We wish the 2020 winner Professor Daniel J. Mindiola a huge congratulations!

 

You can find out more about the F. Albert Cotton Award in Synthetic Inorganic Chemistry on the website.

 

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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HOT articles: January

We are pleased to share a selection of our referee-recommended HOT articles for January. We hope you enjoy reading these articles and congratulations to all the authors whose articles are featured! As always, Chemical Science is free to read & download. You can find our full 2020 HOT article collection here.

 

Breaking scaling relations for efficient CO2 electrochemical reduction through dual-atom catalysts
Yixin Ouyang, Li Shi, Xiaowan Bai, Qiang Li and Jinlan Wang
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC05236D

Breaking scaling relations for efficient CO2 electrochemical reduction through dual-atom catalysts

 

Unexpected monolayer-to-bilayer transition of arylazopyrazole surfactants facilitates superior photo-control of fluid interfaces and colloids
Christian Honnigfort, Richard A. Campbell, Jörn Droste, Philipp Gutfreund, Michael Ryan Hansen, Bart Jan Ravoo and Björn Braunschweig
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC05490A

Unexpected monolayer-to-bilayer transition of arylazopyrazole surfactants facilitates superior photo-control of fluid interfaces and colloids

 

Type 3 porous liquids based on non-ionic liquid phases – a broad and tailorable platform of selective, fluid gas sorbents
John Cahir, Min Ying Tsang, Beibei Lai, David Hughes, M. Ashraf Alam, Johan Jacquemin, David Rooney and Stuart L. James
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC05770F

Type 3 porous liquids based on non-ionic liquid phases – a broad and tailorable platform of selective, fluid gas sorbents

 

A programmable chemical switch based on triggerable Michael acceptors
Jiaming Zhuang, Bo Zhao, Xiangxi Meng, Jessica D. Schiffman, Sarah L. Perry, Richard W. Vachet and S. Thayumanavan
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC05841A

 

Simulating protein–ligand binding with neural network potentials
Shae-Lynn J. Lahey and Christopher N. Rowley
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC06017K

Simulating protein–ligand binding with neural network potentials

 

Efficient white polymer light-emitting diodes (WPLEDs) based on covalent-grafting of [Zn2(MP)3(OAc)] into PVK
Guorui Fu, Yani He, Wentao Li, Tiezheng Miao, Xingqiang Lü, Hongshan He, Li Liu c and Wai-Yeung Wong
Chem. Sci., 2020, Advance Article
DOI: 10.1039/C9SC05288G

Efficient white polymer light-emitting diodes (WPLEDs) based on covalent-grafting of [Zn2(MP)3(OAc)] into PVK

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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For catalysis, do you need one gold or two?

Doesn’t everyone love gold? Not only is it shiny and pretty in macroscopic form, but it’s one of the best-behaved nanoscale systems and the focus of extensive catalysis study. While much is known about the mechanisms of many gold-catalyzed reactions, a question of whether a number of organogold complexes are actual intermediates or off-cycle sinks remains. Catalysis of the nucleophilic addition of water to alkynes via gold complexes is a reaction with multiple hypothesized active intermediates and reaction pathways. Initially thought to occur via monoaurated species, subsequent work proposed activation by multiple gold catalysts. The problem, as seen in figure 1, is that the two pathways are connected and the presence of any specific intermediates can’t rule either pathway out.

Figure 1. Reaction scheme with potential intermediates for nucleophile addition to an alkyne via a gold-catalyzed pathway.

To solve this problem, researchers in the Czech Republic and the Netherlands developed a method to probe solution-phase intermediates with electrospray ionization mass spectrometry (ESI-MS) called Delayed Reactant Labeling. To do this, one of the reactants must be a mixture of isotopically labeled and unlabeled molecules, added separately with a time delay. This helps eliminate ionization artifacts and moves the reaction away from steady state conditions to allow for kinetic modeling. Using this technique, combined with other more standard characterization methods like NMR and infrared (IR) spectroscopy, the researchers studied gold-catalyzed water addition to alkynes. The catalyst is known to form digold hydroxides in the presence of water, which lends credence to the idea that a digold species is involved in the catalysis. Based on kinetic restrictions, they studied the addition of water to 1-phenylpropyne, which produces a mixture of regioisomers of intermediates that was a bit challenging to deconvolute. The initial ESI-MS spectra show the presence of both mono- and diaurated species and the different fragments were isolated, analyzed by IR photodissociation, and the spectra compared to theoretical models to corroborate their identity.

These results set the stage for the Delayed Reactant Labeling studies using deuterated 1-phenylpropyne. After the reaction reached equilibrium, in this case about 40 minutes, the labeled reactant was added to then allow for kinetic fitting of the intermediates. They determined that under standard conditions the monoaurated species has a half life of approximately 9 minutes and the diaurated species has a half life of 7 minutes. These decay constants could be altered by adding organic acids to degrade the complexes faster, while attempts to trap the species as salts were unsuccessful. Upon reaction with D2O a kinetic isotope effect doubling the lifetimes was observed and suggests that the mechanism is likely the same for all intermediates and that it involves a hydrogen/proton transfer. The two types of species also have slightly different rates of formation, with the diaurated species likely having a higher turn-over frequency. However, there isn’t a dramatic difference between the kinetics of these two types of intermediates.

Figure 2. Example of a) spectra obtained from the delayed reactant labeling method and b) fits of peak intensities over time used to extract kinetic information.

In order to determine which of the intermediates is catalytically relevant, the researchers changed the substrate to 3-hexyne. The symmetric alkyne has no regioisomeric intermediates to convolute the data, but the reaction kinetics are much faster and therefore not suited to the prior mechanistic studies. By adding an excess of acid, the rate determining step was moved from protodeauration.  Under these conditions, the rate has a linear dependence on the gold complex and likely proceeds primarily via monoaurated intermediates. This approach combining multiple analytical techniques elucidated the role of various gold-containing intermediates and demonstrated the utility of ESI-MS as a tool for determining reaction kinetics.

To find out more, please read:

Monoaurated vs. diaurated intermediates: causality or independence?

Mariarosa Anania, Lucie Jašková, Jan Zelenka, Elena Shcherbachenko, Juraj Jašk and Jana Roithová

Chem. Sci., 2020, Advance Article

About the blogger:

Beth Mundy is a PhD candidate in chemistry in the Cossairt lab at the University of Washington in Seattle, Washington. Her research focuses on developing new and better ways to synthesize nanomaterials for energy applications. She is often spotted knitting in seminars or with her nose in a good book. You can find her on Twitter at @BethMundySci.

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Congratulations to the Poster Prize winners at IPEROP!

Congratulations to all three Royal Society of Chemistry Poster Presentation Prize winners at this year’s Perovskite, Organic Photovoltaics and Optoelectronics conference, IPEROP, in Tsukuba, Japan 20 – 22 January!

Chemical Science Executive Editor May Copsey attended and presented the awards to the three winners.

 

Koichiro Kamimori Simone Mastroianni Ryota Jono

 

 

Chemical Science, Royal Society of Chemistry

Submit to Chemical Science today! Check out our author guidelines for information on our article types or find out more about the advantages of publishing in a Royal Society of Chemistry journal.

Keep up to date with our latest articles, reviews, collections & more by following us on Twitter. You can also keep informed by signing up to our E-Alerts.

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