Aaron Micallef

Exploitation of the Menshutkin Reaction for the Controlled Assembly of Halogen Bonded Architectures Incorporating 1,2-Diiodotetrafluorobenzene and 1,3,5-Triiodotrifluorobenzene

Publisher: American Chemical Society (ACS)

Date: 10-01-2012

DOI: 10.1021/CG201017R

Halogen-Bond-Modulated Organization of [Ni(terpy-ph)2]I2 Complexes in Heteromeric Three-Component Systems

Publisher: American Chemical Society (ACS)

Date: 25-07-2019

DOI: 10.1021/ACS.CGD.9B00802

Synthesis of nitroxide-functionalized phthalocyanines

Publisher: Elsevier BV

Date: 06-2007

DOI: 10.1016/J.TET.2007.03.170

CCDC 1019351: Experimental Crystal Structure Determination

Publisher: No publisher found

Date: 2014

DOI: 10.5517/CC136Q9B

The vibrational group frequency of the N-O stretching band of nitroxide stable free radicals

Publisher: Elsevier BV

Date: 09-2008

DOI: 10.1016/J.SAA.2007.08.017

Abstract: The group frequency of the N-O radical stretching vibration has received scant attention in the literature. The few existing treatments of the vibrational spectroscopy of nitroxides are incomplete at best and potentially misleading to workers in the field. To close this gap in the available knowledge, the existing literature on the vibrational spectra of nitroxide stable free radicals is critically reviewed with particular reference to the wavenumber position of the N-O* stretching vibration, nu(N-O*). Poor evidentiary bases for the assignment nu(N-O) were found in many instances. Ab initio Density Field Theory calculations using a model chemistry of UB3LYP at the 6-311++G(d,p) level were performed to obtain a theoretical band position of nu(N-O) for comparison with the published data. Large discrepancies between the theoretical and experimental values were found for the radical 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxyl, which currently sets the lower limit of the accepted wavenumber range of nu(N-O*), as well as for the nitronyl and iminyl nitroxides. The wavenumber position of nu(N-O*) was found to occur in the range 1450-1420cm(-1) for 5-membered cyclic nitroxides and 1395-1340cm(-1) for 6-membered cyclic and acyclic nitroxides. In nitronyl nitroxides, the symmetric stretching vibration occurs in the region 1470cm(-1), but coupling to other modes makes specific band assignments problematic for the nitronyl nitroxide group.

Electron spin–lattice relaxation of nitroxyl radicals in temperature ranges that span glassy solutions to low-viscosity liquids

Publisher: Elsevier BV

Date: 03-2008

DOI: 10.1016/J.JMR.2007.12.003

Perylene-based profluorescent nitroxides for the rapid monitoring of polyester degradation upon weathering: An assessment

Publisher: Elsevier BV

Date: 10-2013

DOI: 10.1016/J.POLYMDEGRADSTAB.2013.07.006

Three-Way Switchable Single-Crystal-to-Single-Crystal Solvatomorphic Spin Crossover in a Molecular Cocrystal

Publisher: American Chemical Society (ACS)

Date: 20-11-2020

DOI: 10.1021/ACS.CHEMMATER.0C03396

Controlling Spin Switching with Anionic Supramolecular Frameworks

Publisher: American Chemical Society (ACS)

Date: 04-03-2020

DOI: 10.1021/ACS.CHEMMATER.0C00375

Isostructural Co-crystals Derived from Molecules with Different Supramolecular Topologies

Publisher: American Chemical Society (ACS)

Date: 02-09-2014

DOI: 10.1021/CG501210T

Halogen bonding between an Isoindoline Nitroxide and 1,4-Diiodotetrafluorobenzene: New tools and tectons for self-assembling organic spin systems

Publisher: Wiley

Date: 03-04-2009

DOI: 10.1002/CHEM.200801920

Abstract: Radical assembly: Halogen bonding has been observed for the first time between an isoindoline nitroxide and an iodoperfluorocarbon (see figure), which cocrystallize to form a discrete 2:1 supramolecular compound in which N--O(.)I halogen bonding is the dominant intermolecular interaction. This illustrates the potential use of halogen bonding and isoindoline nitroxide tectons for the assembly of organic spin systems.The isoindoline nitroxide 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO) and 1,4-diiodotetrafluorobenzene readily form a discrete 2:1 complex that shows evidence of relatively strong N--O(.)I halogen bonding. This interaction was characterized in the solid state by single-crystal X-ray analysis, thermal analysis, and vibrational spectroscopy (IR and Raman), backed by density functional theory calculations. EPR spectroscopy performed on a solution of TMIO in pentafluoroiodobenzene, a halogen-bonding donor, indicates that halogen bonding induces an increase in electron density at the nitroxide nitrogen nucleus and an increase in the nitroxide rotational correlation time. Our findings demonstrate the potential of utilizing halogen-bonding interactions to promote the self-assembly of new isoindoline nitroxide tectons for the preparation of organic spin systems.

Interplay between the Supramolecular Motifs of Polypyridyl Metal Complexes and Halogen Bond Networks in Cocrystals

Publisher: American Chemical Society (ACS)

Date: 22-01-2016

DOI: 10.1021/ACS.CGD.5B01211

Profluorescent nitroxides: Thermo-oxidation sensors for stabilised polypropylene

Publisher: Elsevier BV

Date: 10-2010

DOI: 10.1016/J.POLYMDEGRADSTAB.2010.06.019

Wellenlängengesteuerte photochemische Synthese von Phenalendiimiden

Publisher: Wiley

Date: 18-03-2021

DOI: 10.1002/ANGE.202016632

CCDC 1019348: Experimental Crystal Structure Determination

Publisher: No publisher found

Date: 2014

DOI: 10.5517/CC136Q67

CCDC 1019350: Experimental Crystal Structure Determination

Publisher: No publisher found

Date: 2014

DOI: 10.5517/CC136Q89

Kinetic analysis of nitroxide radical coupling reactions mediated by CuBr

Publisher: Wiley

Date: 08-04-2010

DOI: 10.1002/POLA.23991

Rapid, Selective, and Reversible Nitroxide Radical Coupling (NRC) Reactions at Ambient Temperature

Publisher: American Chemical Society (ACS)

Date: 10-11-2009

DOI: 10.1021/MA9014565

Wavelength‐Gated Photochemical Synthesis of Phenalene Diimides

Publisher: Wiley

Date: 18-03-2021

DOI: 10.1002/ANIE.202016632

Green light LED activated ligation of a scalable, versatile chalcone chromophore

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1PY00533B

Abstract: Herein we present a photoreactive chalcone moiety that can be synthesized at a scale of several grams with ease, and can efficiently undergo a [2 + 2] photocycloaddition with light close to 500 nm as determined by an action plot.

The kinetics and mechanism of interconversion within a system of [Fe₂L₃]⁴⁺ helicates and [Fe₄L₆]⁸⁺ cages

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1CC01583D

Abstract: An interconverting system of self-assembled [Fe 2 L 3 ] 4+ triple helicates and [Fe 4 L 6 ] 8+ tetrahedral cages is reported. The rates of interconversion between these two assemblies were measured allowing for a mechanism of interconversion to be proposed.

Vapour phase assembly of a halogen bonded complex of an isoindoline nitroxide and 1,2-diiodotetrafluorobenzene

Publisher: Royal Society of Chemistry (RSC)

Date: 2011

DOI: 10.1039/C1CE05344B

Highly efficient, stoichiometric radical exchange reactions using isoindoline profluorescent nitroxides

Publisher: Royal Society of Chemistry (RSC)

Date: 2010

DOI: 10.1039/C0PY00015A

A Self-Catalyzed Visible Light Driven Thiol Ligation

Publisher: American Chemical Society (ACS)

Date: 06-05-2021

DOI: 10.1021/JACS.1C03213

The evaluation of new and isotopically labeled isoindoline nitroxides and an azaphenalene nitroxide for EPR oximetry

Publisher: Elsevier BV

Date: 08-2011

DOI: 10.1016/J.JMR.2011.05.007

Development of Scaffolded Online Modules To Support Self-Regulated Learning in Chemistry Concepts

Publisher: American Chemical Society

Date: 2016

DOI: 10.1021/BK-2016-1235.CH001

Impact of molecular size on electron spin relaxation rates of nitroxyl radicals in glassy solvents between 100 and 300 K

Publisher: Informa UK Limited

Date: 10-08-2007

DOI: 10.1080/00268970701724966

Interactions of iodoperfluorobenzene compounds with gold nanoparticles

Publisher: Royal Society of Chemistry (RSC)

Date: 2012

DOI: 10.1039/C2CP23809H

Molar ratio induced crystal transformation from coordination complex to coordination polymers

Publisher: Elsevier BV

Date: 05-2023

DOI: 10.1016/J.CCLET.2023.108542

Conversion of Catalytically Inert 2D Bismuth Oxide Nanosheets for Effective Electrochemical Hydrogen Evolution Reaction Catalysis via Oxygen Vacancy Concentration Modulation

Publisher: Springer Science and Business Media LLC

Date: 04-2022

DOI: 10.1007/S40820-022-00832-6

Abstract: Oxygen vacancies ( V o ) in electrocatalysts are closely correlated with the hydrogen evolution reaction (HER) activity. The role of vacancy defects and the effect of their concentration, however, yet remains unclear. Herein, Bi 2 O 3 , an unfavorable electrocatalyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy (Δ G H* ), is utilized as a perfect model to explore the function of V o on HER performance. Through a facile plasma irradiation strategy, Bi 2 O 3 nanosheets with different V o concentrations are fabricated to evaluate the influence of defects on the HER process. Unexpectedly, while the generated oxygen vacancies contribute to the enhanced HER performance, higher V o concentrations beyond a saturation value result in a significant drop in HER activity. By tunning the V o concentration in the Bi 2 O 3 nanosheets via adjusting the treatment time, the Bi 2 O 3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52 × 10 24 cm −3 demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm −2 , a Tafel slope of 80 mV dec −1 , and an exchange current density of 316 mA cm −2 in an alkaline solution, which approaches the top-tier activity among Bi-based HER electrocatalysts. Density-functional theory calculations confirm the preferred adsorption of H* onto Bi 2 O 3 as a function of oxygen chemical potential (∆ μ O ) and oxygen partial potential ( P O2 ) and reveal that high V o concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity. This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts.

CCDC 1019347: Experimental Crystal Structure Determination

Publisher: No publisher found

Date: 2014

DOI: 10.5517/CC136Q56

CCDC 1019349: Experimental Crystal Structure Determination

Publisher: No publisher found

Date: 2014

DOI: 10.5517/CC136Q78

Assessment of tumor prevention in type 1 Neurofibromatosis using a nitroxide compound

Publisher: EManuscript Technologies

Date: 07-2011

DOI: 10.5530/AX.2011.3.3

Ultrafast and Reversible Multiblock Formation by the SET-Nitroxide Radical Coupling Reaction

Publisher: CSIRO Publishing

Date: 2010

DOI: 10.1071/CH10092

Abstract: The single electron transfer-nitroxide radical coupling (SET-NRC) reaction has been used to produce multiblock polymers with high molecular weights in under 3 min at 50°C by coupling a difunctional telechelic polystyrene (Br-PSTY-Br) with a dinitroxide. The well known combination of dimethyl sulfoxide as solvent and Me6TREN as ligand facilitated the in situ disproportionation of CuIBr to the highly active nascent Cu0 species. This SET reaction allowed polymeric radicals to be rapidly formed from their corresponding halide end-groups. Trapping of these carbon-centred radicals at close to diffusion controlled rates by dinitroxides resulted in high-molecular-weight multiblock polymers. Our results showed that the disproportionation of CuI was critical in obtaining these ultrafast reactions, and confirmed that activation was primarily through Cu0. We took advantage of the reversibility of the NRC reaction at elevated temperatures to decouple the multiblock back to the original PSTY building block through capping the chain-ends with mono-functional nitroxides. These alkoxyamine end-groups were further exchanged with an alkyne mono-functional nitroxide (TEMPO–≡) and ‘clicked’ by a CuI-catalyzed azide/alkyne cycloaddition (CuAAC) reaction with N3–PSTY–N3 to reform the multiblocks. This final ‘click’ reaction, even after the consecutive decoupling and nitroxide-exchange reactions, still produced high-molecular-weight multiblocks efficiently. These SET-NRC reactions would have ideal applications in re-usable plastics and possibly as self-healing materials.

Queensland University Of Technology

Location: Australia

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Linkage Infrastructure, Equipment And Facilities - Grant ID: LE170100144

Start Date: 05-2017

End Date: 11-2017

Amount: $480,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0989946

Start Date: 04-2009

End Date: 12-2010

Amount: $357,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP190102036

Start Date: 01-2019

End Date: 12-2023

Amount: $450,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0883528

Start Date: 05-2009

End Date: 11-2012

Amount: $76,881.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE210100148

Start Date: 07-2021

End Date: 06-2023

Amount: $1,350,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE230100048

Start Date: 03-2023

End Date: 03-2024

Amount: $570,702.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE130100061

Start Date: 2013

End Date: 06-2014

Amount: $710,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0558340

Start Date: 02-2005

End Date: 12-2008

Amount: $250,000.00

Funder: Australian Research Council