Chemical Communications Blog

After years of trying, scientists have finally isolated 1,4-oxazine.¹ Among the many possible 6-membered fully unsaturated parent heterocycles containing one group 15 and one group 16 atom, 1,4-oxazine is the first to be generated and spectroscopically characterised. The closest molecule to be made in the past was a monosubstituted oxazine.² Now, Alan Aitken and colleagues at the University of St Andrews in the UK have used flash vacuum pyrolysis to remove the N–tert-butoxycarbonyl group from the previous attempt and taken the synthesis all the way to 1,4-oxazine. Unsurprisingly, being a non-aromatic system, 1,4-oxazine is very unstable. 

Libraries of small molecules are central to screening processes in biomedical research and this work could aid wider efforts attempting to expand those libraries by developing synthetic routes to nitrogen-containing heterocyclic scaffolds. 

You can read this article in Chemistry World» 

Read the original journal article in ChemComm:
1,4-Oxazine
R. Alan Aitken, Kati M. Aitken, Philip G. Carruthers, Marc-Alexandre Jean and Alexandra M. Z. Slawin  
Chem. Commun., 2013,49, 11367-11369, DOI: 10.1039/C3CC47801G

pH-Triggered Au-fluorescent mesoporous silica nanoparticles for 19F MR/fluorescent multimodal cancer cellular imaging
Shizhen Chen, Yuqi Yang, Haidong Li, Xin Zhou and Maili Liu
Chem. Commun., 2013, Advance Article
DOI: 10.1039/C3CC47324D, Communication

Free to access until 15th December 2013

Nitrogenase: a general hydrogenator of small molecules
Ian Dance
Chem. Commun., 2013,49, 10893-10907
DOI: 10.1039/C3CC46864J, Feature Article

Free to access until 15th December 2013

Epoxidation of bromoallenes connects red algae metabolites by an intersecting bromoallene oxide – Favorskii manifold
D. Christopher Braddock, James Clarke and Henry S. Rzepa
Chem. Commun., 2013,49, 11176-11178
DOI: 10.1039/C3CC46720A, Communication

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Differential interference contrast microscopy imaging of micrometer-long plasmonic nanowires
Ji Won Ha, Kuangcai Chen and Ning Fang
Chem. Commun., 2013,49, 11038-11040
DOI: 10.1039/C3CC46871B, Communication
From themed collection Structure and chemistry of materials from in-situ electron microscopy

Free to access until 15th December 2013

Stereocontrolled synthesis of the oxathiabicyclo[3.3.1]nonane core structure of tagetitoxin
Hitomi Yamada, Masaatsu Adachi and Toshio Nishikawa
Chem. Commun., 2013,49, 11221-11223
DOI: 10.1039/C3CC46949B, Communication

Free to access until 15th December 2013

Incorporation by coordination and release of the iron chelator drug deferiprone from zinc-based metal–organic frameworks
Andrew D. Burrows, Monika Jurcic, Luke L. Keenan, Rebecca A. Lane, Mary F. Mahon, Mark R. Warren, Harriott Nowell, Michael Paradowski and John Spencer
Chem. Commun., 2013,49, 11260-11262
DOI: 10.1039/C3CC45689G, Communication

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A mixed dicarboxylate strut approach to enhancing catalytic activity of a de novo urea derivative of metal–organic framework UiO-67
Paul W. Siu, Zachary J. Brown, Omar K. Farha, Joseph T. Hupp and Karl A. Scheidt
Chem. Commun., 2013,49, 10920-10922
DOI: 10.1039/C3CC47177B, Communication

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A new technique for the accurate and fast detection of amino acids has been developed by researchers in the US. The simple method, employing cucurbiturils and the lanthanide europium, could light the way to improvements in nutritional analysis and drug detection.  

Amino acids are essential building blocks for all living beings. Abnormal amino acid levels can indicate underlying health problems such as malnutrition, pancreatitis and Alzheimer’s disease. Conventional amino acid sensing techniques involve chromatography or electrochemical methods, which can be costly and must be performed by skilled operators.  

The method proposed by Pavel Anzenbacher Jr and coworkers at Bowling Green State University in Ohio analyses fluorescence signals when guest europium ions are displaced from an array of two cucurbituril host probes. One of the probes is cylindrical and prefers to bind smaller molecules in a host–guest fashion, whilst the other is a larger linear molecule that wraps around larger analytes.  

Probe fluorescence is quenched when an Eu ion is bound. When the Eu is displaced by an analyte, the fluorescence is "turned-on"

 Read the full article in Chemistry World»  

Read the original journal article in ChemComm:
“Turn-on” fluorescent sensor array for basic amino acids in water
Tsuyoshi Minami, Nina A. Esipenko, Ben Zhang, Lyle Isaacs and Pavel Anzenbacher  
Chem. Commun., 2014, Advance Article, DOI: 10.1039/C3CC47416J

Cobalt-based crystal surrounded by nickel-based crystal (top) and cobalt-based crystal surrounded by zinc-based crystal (bottom)

Scientists based in France are behind these peculiar looking crystals. Sylvie Ferlay, Mir Wais Hosseini and colleagues at the University of Strasbourg used a molecular tectonics strategy to prepare the crystals. In molecular tectonics, building blocks, called tectons, are designed to recognise each other so that they self-assemble into molecular networks when placed together.

Combining M²⁺ cations (where M = Co, Ni, Cu or Zn) with 2,4,6-pyridinetricarboxylic acid, bisamidinium dications and sodium hydroxide resulted in metal complexes that interconnected into single crystals of different colours depending on the metal cation. Single crystals based on one metal were then immersed in a solution containing the same ligand (2,4,6-pyridinetricarboxylic acid) and organic tectons (bisamidinium dications) and a different metal cation. The single crystals acted as seeds for the crystallisation of the coordination polymer of the different metal cation since the unit cells fitted almost perfectly to each other. Single crystals of one compound grew around the single crystal of another  to give a crystal within a crystal.

This crystal engineering strategy is a powerful tool for preparing crystalline materials with different crystalline domains, the researchers say. It just leaves us to wonder how many coloured stripes could be added on?

You can also read this article in Chemistry World

Read the original journal article in ChemComm:
Molecular tectonics: from crystals to crystals of crystals
Gabriela Marinescu, Sylvie Ferlay, Nathalie Kyritsakas and Mir Wais Hosseini  
Chem. Commun., 2013,49, 11209-11211, DOI: 10.1039/C3CC45205K

Supramolecular architecture, crystal structure and transport properties of the prototypal oxobenzene-bridged bisdithiazolyl radical conductor
Joanne W. L. Wong, Aaron Mailman, Stephen M. Winter, Craig M. Robertson, Rebecca J. Holmberg, Muralee Murugesu, Paul A. Dube and Richard T. Oakley
Chem. Commun., 2013, Advance Article
DOI: 10.1039/C3CC46686H, Communication

Free to access until 1st December 2013

Synthesis of a metal-free coordinating ring via formation of a cleavable [2]catenane
Frédéric Niess and Jean-Pierre Sauvage
Chem. Commun., 2013,49, 10790-10792
DOI: 10.1039/C3CC46452K, Communication

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Expanding the scope of oxime ligation: facile synthesis of large cyclopeptide-based glycodendrimers
Baptiste Thomas, Nathalie Berthet, Julian Garcia, Pascal Dumy and Olivier Renaudet
Chem. Commun., 2013,49, 10796-10798
DOI: 10.1039/C3CC45368E, Communication

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A FRET-based ratiometric fluorescent and colorimetric probe for the facile detection of organophosphonate nerve agent mimic DCP
Weimin Xuan, Yanting Cao, Jiahong Zhou and Wei Wang
Chem. Commun., 2013,49, 10474-10476
DOI: 10.1039/C3CC46095A, Communication

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Gold plating of silver nanoparticles for superior stability and preserved plasmonic and sensing properties
Nimer Murshid, Ilya Gourevich, Neil Coombs and Vladimir Kitaev
Chem. Commun., 2013, Advance Article
DOI: 10.1039/C3CC46075D, Communication

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In situ atomic imaging of coalescence of Au nanoparticles on graphene: rotation and grain boundary migration
Jong Min Yuk, Myoungho Jeong, Sang Yun Kim, Hyeon Kook Seo, Jihyun Kim and Jeong Yong Lee
Chem. Commun., 2013, Advance Article
DOI: 10.1039/C3CC46545D, Communication
From themed collection Structure and chemistry of materials from in-situ electron microscopy

Free to access until 1st December 2013

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