Professor Michelle Coote is a graduate of the University of New South Wales, where she completed a B.Sc. (Hons) in industrial chemistry (1995), followed by a Ph.D. in polymer chemistry (2000). Following postdoctoral work at the University of Durham, UK, she joined the Research School of Chemistry, Australian National University in 2001, initially as a postdoctoral fellow with Professor Leo Radom. She established her own research group in 2004 and was promoted to Professor in 2011. She has published extensively in the fields of polymer chemistry, radical chemistry and computational quantum chemistry, and is a member of the ARC Centre of Excellence for Electromaterials Science. She has received many awards including the 2001 IUPAC prize for young scientists, the RACI Cornforth medal (2000), Rennie medal (2006) David Sangster Polymer Science and Technology Achievement Award (2010) and HG Smith medal (2016), the Le Fevre Memorial Prize of the Australian Academy of Science (2010) and the Pople Medal of the Asia-Pacific Association for Theoretical and Computational Chemistry (2015). In 2014, she was elected to the Fellowship of the Australian Academy of Science.
Using quantum-chemical calculations and kinetic modelling, we reveal the dominant reaction pathwa... more Using quantum-chemical calculations and kinetic modelling, we reveal the dominant reaction pathway in polymer autoxidation, (i) whether oxygen promotes or hamper degradation and (ii) how defects in the polymer backbone affect degradation.
Computational studies show that the activity of ATRP catalysts can be dramatically improved using... more Computational studies show that the activity of ATRP catalysts can be dramatically improved using quinuclidine bridgehead ligands.
A predictive scheme for ranking the inherent stabilities of carbon- and heteroatom-centred radica... more A predictive scheme for ranking the inherent stabilities of carbon- and heteroatom-centred radicals on the same relative scale is presented.
Physical chemistry chemical physics : PCCP, Jan 24, 2016
High-level ab initio calculations are used to identify the mechanism of secondary (and primary) a... more High-level ab initio calculations are used to identify the mechanism of secondary (and primary) alkylperoxyl radical termination and explain why their reactions are much faster than their tertiary counterparts. Contrary to existing literature, the decomposition of both tertiary and non-tertiary tetroxides follows the same asymmetric two-step bond cleavage pathway to form a caged intermediate of overall singlet multiplicity comprising triplet oxygen and two alkoxyl radicals. The alpha hydrogen atoms of non-tertiary species facilitate this process by forming unexpected CHO hydrogen bonds to the evolving O2. For non-tertiary peroxyls, subsequent alpha hydrogen atom transfer then yields the experimentally observed non-radical products, ketone, alcohol and O2, whereas for tertiary species, this reaction is precluded and cage escape of the (unpaired) alkoxyl radicals is a likely outcome with important consequences for autoxidation.
This is a set of 62 prototypes found using topological descriptors. Geometries have been optimise... more This is a set of 62 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
This is a set of 5 archetypes and 11 prototypes found using topological descriptors. Geometries h... more This is a set of 5 archetypes and 11 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
This is a set of 13 archetypes and 66 prototypes found using topological descriptors. Geometries ... more This is a set of 13 archetypes and 66 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
The full catalytic cycle of the proline-catalyzed intermolecular aldol reaction of acetone and p-... more The full catalytic cycle of the proline-catalyzed intermolecular aldol reaction of acetone and p-nitrobenzaldehyde in acetone solvent has been investigated by quantum chemistry at the G3(MP2,CC)//M062X/6–31+G(d)/SMD level of theory, and the results used to develop an ab initio kinetic model. Proline catalyzes the aldol reaction according to the enamine mechanism. The initial reaction between proline and acetone was reinvestigated, and a revised mechanism for enamine formation is proposed in which a second proline assists the process contributing to the enamine formation. Using various initial concentrations of proline while keeping the experimental ratio of water, aldehyde and acetone constant, we find that the enamine formation from the first-order to proline pathway dominates when the concentration of proline is low (< 0.005 M); while the second-order enamine formation pathways contribute and then dominate as the proline concentration is increased. The relative rates of formation of the syn and anti-enamine are not important, as these interconvert via C–N bond rotation and equilibrate faster than their subsequent reaction, which follows the standard Houk/List mechanism. While the stereochemistry can be predicted from an analysis of the alternative C–C bond formation pathways, their relative contributions to the major and minor product yields are influenced by their subsequent rates of hydrolysis. Indeed, while C–C bond formation is normally considered rate determining, our kinetic simulations show that the kinetic model is more complicated than this and under typically used concentrations, the process of initial enamine formation, C–C bond formation and the initial stages of product release all contribute to the overall reaction rate. Using our kinetic model, we predict that yield and %ee are optimal for concentrations of [proline] = 0.005 M, [acetone] = 2.25 M, [aldehyde] = 0.1 M, and [water] = 0.6 M. Using excess acetone (up to 2.6 M) increases both conversion and %ee. Excess aldehyde increases %ee but decreases conversion, and excess catalyst increases the conversion but decreases %ee. Aside from the indirect effect of increasing the solubility of the proline catalyst, water increases both conversion and %ee up to a point, but at large concentrations (> 1.0 M) excess water is expected to decrease %ee. Side reactivity, including aldol condensation, acetone self-aldolization, oxazolidinone formation and azomethine and 1-oxapyrrolizidine formation were all considered in our kinetic model but shown to have a negligible effect (< 2%) on the yield and %ee over the full range of reaction conditions investigated.
Two robust hexacationic cages incorporating either urea or isophthalamide motifs were synthesized... more Two robust hexacationic cages incorporating either urea or isophthalamide motifs were synthesized via a short and high-yielding synthetic pathway using hydrazone condensation reactions in water for the cage forming step. Stability testing revealed that the cages are stable to a range of stimuli in water and in organic solvents. The urea containing cage can bind anions in pure water, and displays strong and selective binding of SO42– over HPO42–. The isophthalamide containing cage binds SO42– only weakly in 1:1 D2O:d6-DMSO but displays strong and cooperative binding of two HPO42– anions. Combined quantum mechanical/annealed molecular dynamics simulations suggest that the remarkable differences in anion selectivity are largely a result of the differing flexibilities of the two cages.
Using quantum-chemical calculations and kinetic modelling, we reveal the dominant reaction pathwa... more Using quantum-chemical calculations and kinetic modelling, we reveal the dominant reaction pathway in polymer autoxidation, (i) whether oxygen promotes or hamper degradation and (ii) how defects in the polymer backbone affect degradation.
Computational studies show that the activity of ATRP catalysts can be dramatically improved using... more Computational studies show that the activity of ATRP catalysts can be dramatically improved using quinuclidine bridgehead ligands.
A predictive scheme for ranking the inherent stabilities of carbon- and heteroatom-centred radica... more A predictive scheme for ranking the inherent stabilities of carbon- and heteroatom-centred radicals on the same relative scale is presented.
Physical chemistry chemical physics : PCCP, Jan 24, 2016
High-level ab initio calculations are used to identify the mechanism of secondary (and primary) a... more High-level ab initio calculations are used to identify the mechanism of secondary (and primary) alkylperoxyl radical termination and explain why their reactions are much faster than their tertiary counterparts. Contrary to existing literature, the decomposition of both tertiary and non-tertiary tetroxides follows the same asymmetric two-step bond cleavage pathway to form a caged intermediate of overall singlet multiplicity comprising triplet oxygen and two alkoxyl radicals. The alpha hydrogen atoms of non-tertiary species facilitate this process by forming unexpected CHO hydrogen bonds to the evolving O2. For non-tertiary peroxyls, subsequent alpha hydrogen atom transfer then yields the experimentally observed non-radical products, ketone, alcohol and O2, whereas for tertiary species, this reaction is precluded and cage escape of the (unpaired) alkoxyl radicals is a likely outcome with important consequences for autoxidation.
This is a set of 62 prototypes found using topological descriptors. Geometries have been optimise... more This is a set of 62 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
This is a set of 5 archetypes and 11 prototypes found using topological descriptors. Geometries h... more This is a set of 5 archetypes and 11 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
This is a set of 13 archetypes and 66 prototypes found using topological descriptors. Geometries ... more This is a set of 13 archetypes and 66 prototypes found using topological descriptors. Geometries have been optimised at the wB97X-D3/6-31G*(d) level of theory and have been taken from CCCBDB. All files are in XYZ format, and the naming convention is ID_A.xyz or ID_P.xyz, where ID is the unique ID number and A (or P) denotes archetype (or prototype). Archetypes were found using archetypal analysis and prototypes were found using k-means clustering. A table is provided in the supporting documents with ID, casno, charge and multiplicity information.
The full catalytic cycle of the proline-catalyzed intermolecular aldol reaction of acetone and p-... more The full catalytic cycle of the proline-catalyzed intermolecular aldol reaction of acetone and p-nitrobenzaldehyde in acetone solvent has been investigated by quantum chemistry at the G3(MP2,CC)//M062X/6–31+G(d)/SMD level of theory, and the results used to develop an ab initio kinetic model. Proline catalyzes the aldol reaction according to the enamine mechanism. The initial reaction between proline and acetone was reinvestigated, and a revised mechanism for enamine formation is proposed in which a second proline assists the process contributing to the enamine formation. Using various initial concentrations of proline while keeping the experimental ratio of water, aldehyde and acetone constant, we find that the enamine formation from the first-order to proline pathway dominates when the concentration of proline is low (< 0.005 M); while the second-order enamine formation pathways contribute and then dominate as the proline concentration is increased. The relative rates of formation of the syn and anti-enamine are not important, as these interconvert via C–N bond rotation and equilibrate faster than their subsequent reaction, which follows the standard Houk/List mechanism. While the stereochemistry can be predicted from an analysis of the alternative C–C bond formation pathways, their relative contributions to the major and minor product yields are influenced by their subsequent rates of hydrolysis. Indeed, while C–C bond formation is normally considered rate determining, our kinetic simulations show that the kinetic model is more complicated than this and under typically used concentrations, the process of initial enamine formation, C–C bond formation and the initial stages of product release all contribute to the overall reaction rate. Using our kinetic model, we predict that yield and %ee are optimal for concentrations of [proline] = 0.005 M, [acetone] = 2.25 M, [aldehyde] = 0.1 M, and [water] = 0.6 M. Using excess acetone (up to 2.6 M) increases both conversion and %ee. Excess aldehyde increases %ee but decreases conversion, and excess catalyst increases the conversion but decreases %ee. Aside from the indirect effect of increasing the solubility of the proline catalyst, water increases both conversion and %ee up to a point, but at large concentrations (> 1.0 M) excess water is expected to decrease %ee. Side reactivity, including aldol condensation, acetone self-aldolization, oxazolidinone formation and azomethine and 1-oxapyrrolizidine formation were all considered in our kinetic model but shown to have a negligible effect (< 2%) on the yield and %ee over the full range of reaction conditions investigated.
Two robust hexacationic cages incorporating either urea or isophthalamide motifs were synthesized... more Two robust hexacationic cages incorporating either urea or isophthalamide motifs were synthesized via a short and high-yielding synthetic pathway using hydrazone condensation reactions in water for the cage forming step. Stability testing revealed that the cages are stable to a range of stimuli in water and in organic solvents. The urea containing cage can bind anions in pure water, and displays strong and selective binding of SO42– over HPO42–. The isophthalamide containing cage binds SO42– only weakly in 1:1 D2O:d6-DMSO but displays strong and cooperative binding of two HPO42– anions. Combined quantum mechanical/annealed molecular dynamics simulations suggest that the remarkable differences in anion selectivity are largely a result of the differing flexibilities of the two cages.
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