Call for papers: 2015 themed issues

Dalton Transactions coverWe are delighted to announce three new Dalton Transactions themed issues to be published in 2015:

Luminescent Complexes and Materials for Light-Emitting Devices
Guest Editor: Dr Eli Zysman-Colman (University of St. Andrews)
Deadline: 6th October 2014

Perovskites
Guest Editors: Professors Russell Morris, Philip Lightfoot (both University of St. Andrews) and J. Paul Attfield (The University of Edinburgh)
Deadline: 16th December 2014

Earth Abundant Element Compounds in Homogeneous Catalysis
Guest Editors: Professors Philip Mountford (University of Oxford), Laurel L. Schafer (University of British Columbia) and Warren E. Piers (University of Calgary)
Deadline: 14th January 2015

New Talent Asia
Guest Editor: Professor Hiroshi Nishihara (The University of Tokyo)
Deadline: 24th February 2015

Does your research fit into any of these subject areas? If so, we would welcome your contribution. For further details on issue scopes and on how to submit, see below:

How to submit

All types of manuscript – communications, full papers and Perspectives, will be considered for publication. The manuscript should be prepared according to our article guidelines and submitted via our online system.

All manuscripts will be subject to normal peer review and inclusion in the themed issue will be at the discretion of the Guest Editors. Please indicate in your submission which themed issue you would like to be considered for.

Issue scopes

Luminescent Complexes and Materials for Light-Emitting Devices
This themed issue will highlight the latest research in the field of luminescent complexes and materials for light-emitting devices. Suitable topics include the synthesis and fundamental photophysical studies of luminescent complexes as well as the fabrication and testing of devices which incorporate these materials. Contributions covering computational studies on relevant materials will also be appropriate.

Perovskites
This issue will focus on functional perovskites from the inorganic chemist’s perspective. It will include, but is not limited to: experimental studies on the synthesis, structure and physical/chemical properties of perovskites; chemistry-structure-property relationships; and the design and understanding of perovskite structure and functionality from a theoretical/computational perspective. Contributions are not limited to ‘classical’ inorganic perovskites but can also include hybrid perovskites, ‘MOF’ perovskites, layered perovskite families and related phases (eg. tungsten bronze types).

Earth Abundant Element Compounds in Homogeneous Catalysis
The aim of this themed issue is to showcase the latest research in the development of highly active and selective homogeneous catalysts utilizing earth abundant elements from across the Periodic Table. We believe this will reflect a recent trend in catalysis that seeks to find alternatives to catalysts based on precious metals like Ru, Rh, Pd, Ag, Re, Os, Ir, Pt, or Au and toxic elements like Hg, Bi, In and Pb. We are inviting contributions from researchers utilizing catalysts based on elements from both the s and p block, the more abundant first row transition metals and the lanthanides as catalysts for commodity chemical, fine chemical and polymer synthesis, to emphasise the broad range of activity in this area.

New Talent Asia
This themed issue will focus on all areas of inorganic and organometallic chemistry, inorganic materials science, bioinorganic chemistry and catalysis and aims to reflect the strength and vitality of new inorganic chemistry from the Asia-Pacific region.

Are you interested in contributing? If so, submit your manuscript before the themed issue deadline(s) or contact us for more information

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The Rare BH5

In fall 2008 I visited Boston, where a good friend gave me a tour of Harvard’s chemical laboratories.  Passing by a small office, I saw through the window a thin elderly man in glasses hunched over a desk.  He was turned away from me but the sign on his office said William N. Lipscomb.

Since Lipscomb’s astonishing groundwork beginning in the 1940’s, boranes have provided fascinating examples of the diversity and possibilities of chemical bonding.  Today, boron’s Lewis acidity is widely exploited in catalysis and Frustrated Lewis Pair (FLP) chemistry.

The BH5 molecule, described as BH3 with sigma-bonded dihydrogen bound in an H2 manner, lies at the confluence of many currents of boron chemistry: the activation of hydrogen by FLP’s using borane Lewis acids; three-centre-two-electron bonding; H2 complexes, and the comparison of main group and transition metal chemistry.

In a recent paper in Dalton Transactions, authors Szieberth, Szpisjak, Turczel and Konczol describe BH5 as “rare.”  This is an understatement.  As they report, its existence was confirmed in 1994 by infra-red spectroscopy in an argon matrix at 10-25K temperatures.

In this paper, they present the modelling of the BH5 complex using Natural Bond Order analysis.  Although this has been reported before, the authors use this paper to discern a unique and significant contribution to the stability of η2 H2 borane complexes: the back-donation of electron density from the B-H (or B-R) s-bonds into the σ* orbital of the bound H2, just as electron density from d-orbitals is donated to the H-H σ* orbital in transition metal H2 complexes.  Their description of the Lewis structure of BH5 as a BH3/H2 adduct featuring a three-centre-two electron bond accounts for 99.1% of the electron density.

William Lipscomb passed away on April 14, 2011 at the age of 91.  But I am sure he would be pleased that work within his research area remains vigorously active.

Read the original paper:

The stability of η2-H2 borane complexes – a theoretical investigation
László Könczöl, Gábor Turczel, Tamás Szpisjaka and Dénes Szieberth
Dalton Trans., 2014,43, 13571-13577


Ian Mallov Ian Mallov is currently a Ph.D. student in Professor Doug Stephan’s group at the University of Toronto. His research is focused on synthesizing new Lewis-acidic compounds active in Frustrated Lewis Pair chemistry. He grew up in Truro, Nova Scotia and graduated from Dalhousie University and the University of Ottawa, and worked in chemical analysis in industry for three years before returning to grad school.
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September’s HOT articles

Enjoy a read of Autumn’s crop of HOT articles which are free to access for 4 weeks only!

Our HOT articles have also been compiled into a collection and are available for viewing on our website.

Metal-mediated coupling of amino acid esters with isocyanides leading to new chiral acyclic aminocarbene complexes
Tatyana B. Anisimova, M. Fátima C. Guedes da Silva, Vadim Yu. Kukushkin, Armando J. L. Pombeiro and Konstantin V. Luzyanin
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01917B

Graphical Abstract

Free to access until 27th October 2014


Photoinduced hydrogen evolution by a pentapyridine cobalt complex: elucidating some mechanistic aspects
Elisa Deponti, Alessandra Luisa, Mirco Natali, Elisabetta Iengo and Franco Scandola
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT02269F

Graphical Abstract

Free to access until 27th October 2014


Efficient halogen photoelimination from dibromo, dichloro and difluoro tellurophenes
Elisa I. Carrera and Dwight S. Seferos
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01751J

Graphical Abstract

Free to access until 17th October 2014


Synthesis, structure and catalytic activity of a gold(I) complex containing 1,2-bis(diphenylphosphino)benzene monoxide
Christine Hahn, Leticia Cruz, Amanda Villalobos, Liliana Garza and Samuel Adeosun
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT02116A

Graphical Abstract

Free to access until 17th October 2014


1,3,5-Triferrocenyl-2,4,6-tris(ethynylferrocenyl)-benzene – a new member of the family of multiferrocenyl-functionalized cyclic systems
Ulrike Pfaff, Grzegorz Filipczyk, Alexander Hildebrandt, Marcus Korb and Heinrich Lang
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT02307B

Graphical Abstract

Free to access until 17th October 2014

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Expanding the Utility of Expanded NHCs

Posted on behalf of Marcus Drover, web writer for Dalton Transactions

In their recent paper in Dalton Transactions, Stasch, Jones and co-workers describe the use of bulky ring-expanded N-heterocyclic carbenes (NHCs) for the stabilisation of Group 15 trichlorides, ECl3; E = P, As, Sb.

The authors show that mixing 1:1 solutions of the ring-expanded, 2,6-diisopropylphenyl-subsitutied NHC “6-Dipp” with ECl3 (E = P, As, and Sb) affords satisfactory yields of the corresponding [(6-Dipp)ECl3] adduct, noting that the use of the alternatively-substituted mesityl-substituted carbene (6-Mes) led to a mixture of products thus highlighting the importance of the 6-Dipp ligand for stabilising the adducts.

Adduct formation

The group characterised each adduct using standard means, including NMR spectroscopy and electron-impact (EI) mass spectrometry. In the cases of P and Sb, they were able to use X-ray crystallography to determine the solid state structures of those compounds and observed that each pnictogen centre adopted a saw-horse geometry.

When the researchers tried to reduce these adducts using either KC8 or a Mg(I) derivative, they were mostly unsuccessful, however they were able to reduce [(6-Dipp)PCl3] using the former reagent to form a unique dicationic carbene-stabilized P4 unit. Once again, the authors attributed the stability of this species to the steric profile of the 6-Dipp ligand framework. The X-ray crystal structure of the complex shows a P4-butterfly geometry stabilised by two carbene moieties.

P4 compound

During the course of their reactivity studies, the group identified (6-MesH)2 as a byproduct resulting from reaction of in-situ generated [(6-Mes)PCl3] with KC8. With further optimisation, they revealed that this moiety could be accessed from treatment of [6-MesH]Br with KC8 – marking the first successful reductive coupling of cyclic amidinium ions. Along with NMR and X-ray crystal data, a cyclic voltammetry (CV) study was also performed on (6-MesH)2 to fully characterise this unique species.

The successful syntheses of all these p-block NHC complexes pave the way for new discoveries in fundamental reactivity, bonding, and catalysis employing main group elements, further demonstrating the potential of these elements to perform exciting chemistry.

Read the full article to find out more:

Expanded Ring N-Heterocyclic Carbene Adducts of Group 15 Element Trichlorides: Synthesis and Reduction studies
Anastas Sidiropoulos, Brooke Osborne, Alexandr Simonov, Deepak Dange, Alan Bond, Andreas Stasch and Cameron Jones
Dalton Trans., 2014, DOI: 10.1039/C4DT02074J


Marcus Drover is a Ph.D. student, co-supervised by Professors Laurel Schafer and Jennifer Love at the University of British Columbia. His research is focused on the preparation of low-coordinate RhI and IrI complexes for use in small-molecule reactivity. He grew up in St. John’s, Newfoundland and graduated from Memorial University (MUN) before beginning graduate school in 2012.
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August’s HOT papers

Enjoy a read of our fresh batch of HOT articles which are free to access for 4 weeks only!

Our HOT articles have also been compiled into a collection and are available for viewing on our website.

Unusual assembly of lacunary heteropolymolybdates with cyanometalate fragment
Ya Wang, Ning Jiang, Fengyan Li, Yanzhen Zheng, Lin Xu and Minghui Sun
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01875C

Graphical Abstract

Free to access until 17th October 2014


Structure, stability and photocatalytic H2 production by Cr-, Mn-, Fe-, Co-, and Ni-substituted decaniobate clusters
Jung-Ho Son, Jiarui Wang and William H. Casey
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT02020K

Graphical Abstract

Free to access until 17th October 2014


Light-induced spin-state switching in the mixed crystal series of the 2D coordination network {[Zn1−xFex(bbtr)3](BF4)2}: optical spectroscopy and cooperative effects
Pradip Chakraborty, Cristian Enachescu, Arnaud Humair, Leo Egger, Teresa Delgado, Antoine Tissot, Laure Guénée, Céline Besnard, Robert Bronisz and Andreas Hauser
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01728E

Graphical Abstract

Free to access until 11th September 2014


Two-photon sensitized visible and near-IR luminescence of lanthanide complexes using a fluorene-based donor–π-acceptor diketonate
Adam W. Woodward, Andrew Frazer, Alma R. Morales, Jin Yu, Anthony F. Moore, Andres D. Campiglia, Evgheni V. Jucov, Tatiana V. Timofeeva and Kevin D. Belfield
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01507J

Graphical Abstract

Free to access until 11th September 2014


Low temperature activation of S8, Sered and α-Te with [CpBIGFe(CO)2] radicals
S. Heinl and M. Scheer
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01764A

Graphical Abstract

Free to access until 9th September 2014


Large structural changes upon protonation of Fe4S4 clusters: the consequences for reactivity
Ian Dance and Richard A. Henderson
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01687D

Graphical Abstract

Free to access until 9th September 2014

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Dalton Transactions in Japan

Members of our Editorial Board recently awarded Dalton Transactions certificates to two attendees at conferences in Japan.

The XXVI International Conference on Organometallic Chemistry (ICOMC 2014) was held in Sapporo on 13th – 18th July with over 1100 participants in attendance.

Professors Fryzuk & Mountford

Professor Michael Fryzuk recieving his certificate from Professor Philip Mountford

Professor Philip Mountford (University of Oxford), Chair of the Dalton Transactions Editorial Board, was on hand to present Professor Michael Fryzuk (University of British Columbia) with a certificate commemorating his Dalton Transactions-sponsored lecture.

Professor Fryzuk gave an excellent talk on nitrogen fixation using organometallic species which was well attended by conference delegates.

After the conference, a number of speakers attended a post-ICOMC symposium at Osaka University on 19th July 2014. The meeting was attended by 150 students and local professors and featured talks from Professors Jun Okuda and Matthias Tam (both members of the Dalton Transactions Advisory Board), Professor John Arnold (Dalton Transactions Associate Editor) and Professor Mountford.

John Arnold, Philip Mountford and Kento Kawakita

Mr Kento Kawakita (right) recieving his certificate from Professors John Arnold (left) and Philip Mountford (centre).

50 posters were presented during the conference, with Mr Kento Kawakita, from the group of Professor Kazushi Mashima (Osaka University and Dalton Transactions Advisory Board), being awarded a Dalton Transactions prize for best poster by Professors Mountford and Arnold.

Congratulations to both Professor Fryzuk and Mr Kawakita!

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Breaking zirconacycles is hard to do

In their recent paper in Dalton Transactions, Erker and co-workers describe B(C6F5)3 as an unorthodox probe for the detection of σ ligand character and allenoid-type bonding in substituted zirconocenes.

Chemists have studied the strong Lewis acid, B(C6F5)3 for the past decade, particularly for its uses in frustrated Lewis pairs (FLPs). This small molecule has, however, gained popularity in other areas of chemistry. In catalysis, B(C6F5)3 is commonly employed to generate cationic metal centres by alkyl group abstraction (σ-ligand abstraction) to activate molecular pre-catalysts for use in polymerisation.

Zirconocene cleavage

Expanding the scope beyond alkyl groups, Erker and co-workers showed that B(C6F5)3 can mediate cleavage of Zr-C(sp3) bonds in zirconacycles, creating unique allene coordination complexes. In one instance, they used an unsubstituted zirconacycloallenoid (Zr-CH2-) to synthesise a zwitterionic (η2-allenyl)zirconocene with an allene bond angle close to linearity.

In a second case, they reacted a 4-phenyl substituted zirconacycloallenoid (Zr-CHPh-) to produce a zwitterionic allene-coordinated zirconocene.

In demonstrating such reactivity, the authors lead the way for B(C6F5)3 to act as a standard probe for detecting latent σ ligand character in other molecules.

Interested in finding out more? Read the full article:

Reaction of Five-membered Zirconacycloallenoids with the Strong Lewis Acid B(C6F5)3
Gerald Kehr, Gerhard Erker, Constantin Gabriel Daniliuc, Birgit Wibbeling and Georg Bender
Dalton Trans. 2014, DOI: 10.1039/C4DT01137F


Marcus Drover Marcus Drover is a Ph.D. student, co-supervised by Professors Laurel Schafer and Jennifer Love at the University of British Columbia. His research is focused on the preparation of low-coordinate RhI and IrI complexes for use in small-molecule reactivity. He grew up in St. John’s, Newfoundland and graduated from Memorial University (MUN) before beginning graduate school in 2012.
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HOT articles for July

July brings us a new batch of HOT articles – free to access for 4 weeks only!

Our HOT articles have also been compiled into a collection and are available for viewing on our website.

A series of 3D metal organic frameworks based on [24-MC-6] metallacrown clusters: structure, magnetic and luminescence properties
Kai Wang, Hua-Hong Zou, Zi-Lu Chen, Zhong Zhang, Wei-Yin Sun and Fu-Pei Liang
Dalton Trans., 2014, 43, 12989-12995
DOI: 10.1039/C4DT01593B

Graphical Abstract

Free to access until 20th August 2014


Mechanism of water oxidation by non-heme iron catalysts when driven with sodium periodate
Alexander R. Parent, Takashi Nakazono, Shu Lin, Satoshi Utsunomiya and Ken Sakai
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01188K

Graphical Abstract

Free to access until 13th August 2014


Hybrid photocatalysts using graphitic carbon nitride/cadmium sulfide/reduced graphene oxide (g-C3N4/CdS/RGO) for superior photodegradation of organic pollutants under UV and visible light
Rajendra C. Pawar, Varsha Khare and Caroline Sunyong Lee
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01278J

Graphical Abstract

Free to access until 13th August 2014


NAMI-A is highly cytotoxic toward leukaemia cell lines: evidence of inhibition of KCa 3.1 channels
Serena Pillozzi, Luca Gasparoli, Matteo Stefanini, Mirco Ristori, Massimo D’Amico, Enzo Alessio, Federica Scaletti, Andrea Becchetti, Annarosa Arcangeli and Luigi Messori
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01356E

Graphical Abstract

Free to access until 7th August 2014


Shape evolution of Au nanoring@Ag core–shell nanostructures: diversity from a sole seed
Jingsong Sun, Jindi Wang, Ying Zhang, Pengbo Wan, Liang Luo, Feng Wang and Xiaoming Sun
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT00992D

Graphical Abstract

Free to access until 4th August 2014


Aqueous stability of alumina and silica perhydrate hydrogels: experiments and computations
Yitzhak Wolanov, Avital Shurki, Petr V. Prikhodchenko, Tatiana A. Tripolskaya, Vladimir M. Novotortsev, Rami Pedahzur and Ovadia Lev
Dalton Trans., 2014, Advance Article
DOI: 10.1039/C4DT01024H 

Graphical Abstract
  

Free to access until 4th August 2014

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Hang on to your carbene

Posted on behalf of Ian Mallov, web writer for Dalton Transactions

What we think of as “organic chemistry” doesn’t often focus on the structure and bonding environments of the carbon atom, unlike inorganic chemistry which often does so with heteroatoms.  So I don’t think I’m going far out on a limb when I say that perhaps the key development in the structure and bonding of carbon over the last quarter century has been the isolation and use of the persistent carbene. 

Arduengo carbene

Arduengo carbene

A carbene is a divalent carbon atom possessing two electrons.  Once thought to be unisolable, its history is recent enough that almost all important figures in its development are not only still living to this day, but still working.  Ron Breslow proposed that carbenes could be isolated in 1957, Guy Bertrand isolated a liquid dicarbene in 1989 and, in 1991, Anthony Arduengo reported the first comprehensive solid-state data of the type of carbene that now bears his name (pictured above).  

So why waste the words of a short post blog on historical perspective?

Because the uses of the carbene have fallen almost entirely in one direction.  Primarily, the carbene has been used as a strong s 2-electron donor – attached to many transition metal atoms it forms very stable complexes, and it is relatively easy to vary its size. 

Only recently have the uses of the carbene diverged. 

In a recent Dalton Transactions paper, Arnold, Love and co-workers present work on labile carbenes tethered to rare earth metals by an alkoxy arm.  On rare earth metals – which are much harder Lewis acids than late transition metals – the soft carbene donor and hard metal acceptor are poorer matches.  Thus the carbon-metal bond may break, freeing the carbene for reactivity, while the hard alkoxy arm keeps the ligand tethered to the metal.

carbene reactivity

Reactivity of tethered alkoxycarbene complexes 

The authors present some examples of reactivity, including co-operative activation of pyrroles and alkynes by the carbene and metal centres, as well as outer-sphere interactions in the form of hydrogen bonding between pyrroles and the metal-bound O atom in solution.   Despite these being small steps, they are nonetheless important if the carbene is to find new roles outside stabilising late transition metal centres.

Interested in finding out more? Read the full paper:

Homo- and heteroleptic alkoxycarbene f-element complexes and their reactivity towards acidic N–H and C–H bonds
Polly L. Arnold, Thomas Cadenbach, Isobel H. Marr, Andrew A. Fyfe, Nicola L. Bell, Ronan Bellabarba, Robert P. Tooze and Jason B. Love
Dalton Trans., 2014, DOI10.1039/C4DT01442A


Ian Mallov Ian Mallov is currently a Ph.D. student in Professor Doug Stephan’s group at the University of Toronto. His research is focused on synthesizing new Lewis-acidic compounds active in Frustrated Lewis Pair chemistry. He grew up in Truro, Nova Scotia and graduated from Dalhousie University and the University of Ottawa, and worked in chemical analysis in industry for three years before returning to grad school.
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Enzyme-Inspiration for a New Nanoswitch

Enzymes function as biological catalysts in a wide array of reactions which are essential for sustaining life. They are almost always large protein molecules which adopt complex three dimensional structures, yet are able to remain structurally dynamic in order to allow the function of the enzyme to be switched on and off.

This feature allows an enzyme’s catalytic activity to be active only when required in the metabolic pathway in which it is involved. For this reason, enzymes have long been a source of inspiration to researchers involved in the design and synthesis of artificial molecular switches and machines.

SARS-CoV 3CLpro is a protease enzyme which is involved in the replication and transcription process of the human coronavirus, the virus which causes severe acute respiratory syndrome (SARS). This enzyme is catalytically inactive as a monomer and only functions as a catalyst when it is bound with another monomer in a complex called a homodimer.

Both crystallographic and mutation studies have implicated several amino acid residues in the dimerization process, however the exact mechanism of dimer formation and how this activates the enzyme’s catalytic activity is still unconfirmed.

 Nanoswitch mechanism 

 Scheme 1. Switching between open and close conformations of nanoswitch 1 in response to metal ion addition

Drawing inspiration from this monomer-dimer on-off mechanism, Schmittel and co-workers have devised a molecular switch capable of toggling between monomeric and dimeric forms in response to the addition of different metal ions. With no metal ions present, the triangular framework adopts the ‘OPEN-I’ conformation (Scheme 1). Upon the addition of copper(I) ions, the two pyridine-based ligands come into proximity to mutually coordinate the metal.

This changes the conformation of the framework to the ‘CLOSE’ state. Addition of iron(II) ions to the ‘CLOSE’ state again changes the molecular conformation, as the iron(II) ions occupy the terpyridine moiety and the copper(I) ions move to occupy only the shielded phenanthroline ligand.

This both forms a homoleptic dimer, as the iron(II) ions can coordinate two terpyridine moieties simultaneously from two different molecules, and creates a coordinatively unsaturated copper species which acts as a catalyst for a cyclopropanation reaction. The authors impressively demonstrate the reversibility of each step, with the removal of metal ions changing the framework back to its uncoordinated conformation.

In this way, they have successfully made a molecular switch which responds to a metal ion signal (Fe2+) and turns a catalytic complex on and off. Like SARS-CoV 3CLpro enzyme, the catalytically active state is the homodimer, with the monomeric form being catalytically inactive.

To find out more, read the full article:

A monomer-dimer nanoswitch that mimics the working principle of the SARS-CoV 3CLpro enzyme controls copper-catalysed cyclopropanation
Soumen De, Susnata Pramanik and Michael Schmittle
Dalton Trans. 2014, DOI:10.1039/c4dt01508h


   Dr C. Liana Allen is currently a post-doctoral research associate in the group of Professor Scott Miller at Yale University, where she works on controlling the enantio- or regioselectivity of reactions using small peptide catalysts. Liana received her Ph.D. in organic chemistry at Bath University with Professor Jonathan Williams, where she worked on developing novel, efficient syntheses of amide bonds.
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