Hansjörg Grützmacher | Swiss Federal Institute of Technology (ETH) (original) (raw)
Papers by Hansjörg Grützmacher
Related Article: Tetiana Krachko, Mark Bispinghoff, Aaron M. Tondreau, Daniel Stein, Matthew Bake... more Related Article: Tetiana Krachko, Mark Bispinghoff, Aaron M. Tondreau, Daniel Stein, Matthew Baker, Andreas W. Ehlers, J. Chris Slootweg, Hansjorg Grutzmacher|2017|Angew.Chem.,Int.Ed.|56|7948|doi:10.1002/anie.201703672
Angewandte Chemie, Jul 2, 2010
Scheme 1. Cationic three-membered phosphorus heterocycles (A-C) and BABAR-Phos derivatives D-G. S... more Scheme 1. Cationic three-membered phosphorus heterocycles (A-C) and BABAR-Phos derivatives D-G. Scheme 2. Synthesis of 2 and 3.
Angewandte Chemie
Reaction of the 6π‐electron aromatic four‐membered heterocycle (IPr)2C2P2 (1) (IPr=1,3‐bis(2,6‐di... more Reaction of the 6π‐electron aromatic four‐membered heterocycle (IPr)2C2P2 (1) (IPr=1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐dihydro‐2H‐imidazol‐2‐ylidene) with [Fe2CO9] gives the neutral iron tricarbonyl complex [Fe(CO)3‐η3‐{(IPr)2C2P2}] (2). Oxidation with two equivalents of the ferrocenium salt, [Fe(Cp)2](BArF24), affords the dicationic tricarbonyl complex [Fe(CO)3‐η4‐{(IPr)2C2P2}](BArF24)2 (4). The one‐electron oxidation proceeds under concomitant loss of one CO ligand to give the paramagnetic dicarbonyl radical cation complex [Fe(CO)2‐η4‐{(IPr)2C2P2}](BArF24) (5). Reduction of 5 allows the preparation of the neutral dicarbonyl complex [Fe(CO)2‐η4‐{(IPr)2C2P2}] (6). An analysis by various spectroscopic techniques (57Fe Mössbauer, EPR) combined with DFT calculations gives insight into differences of the electronic structure within the members of this unique series of iron carbonyl complexes, which can be either described as electron precise or Wade–Mingos clusters.
Zeitschrift für anorganische und allgemeine Chemie, 2022
The reaction between [Ru2Cl2(μ2‐Cl)2(CO)6] and the biradicaloid [P(μ‐NTer)]2 proceeds under inser... more The reaction between [Ru2Cl2(μ2‐Cl)2(CO)6] and the biradicaloid [P(μ‐NTer)]2 proceeds under insertion of a Ru(II)Cl(CO)2 fragment into one P−N bond and addition of chloride to the adjacent phosphorus center. Thereby an unprecedented inorganic ruthenacycle is obtained that was investigated by single crystal X‐ray analysis, NMR and IR spectroscopy and DFT calculations. The reactivity of the complex in a halide‐pseudo‐halide exchange reaction and a coordination reaction were investigated.
Dalton Transactions, 2022
This Frontiers article summarizes the reported computational research performed on ruthenium cata... more This Frontiers article summarizes the reported computational research performed on ruthenium catalyzed methanol dehydrogenation reactions performed in the past decade, and serves as a guide for future research.
ChemNanoMat, 2020
The formation of iron phosphide nanoparticles (Fe x P NPs) is a well-studied process. It usually ... more The formation of iron phosphide nanoparticles (Fe x P NPs) is a well-studied process. It usually uses air-sensitive phosphorus precursors such as n-trioctylphosphine or white phosphorus. In this study, we report the synthesis and characterization of a remarkably stable tetrakis(acyl)cyclotetraphosphane, P 4 (MesCO) 4. We demonstrate that this compound can be used as a stoichiometric source of P(0) species in order to synthesize FeP and Fe 2 P nanoparticles at only 250 °C. This tunable process provides a route to monodisperse nanoparticles with different compositions and crystallinities. We combine X-Ray photoelectron spectroscopy (XPS) and atomic pair distribution function (PDF) in order to study the local order and bonding in the amorphous and crystalline materials. We show that crystalline FeP forms via an intermediate amorphous phase (obtained at a lower temperature) that presents local order similar to that of the crystalline sample. From the results of this work, a better understanding of the mechanism of the formation of amorphous and crystalline Fe x P NPs is provided which relies on the use of a stoichiometric and single P-source. We then explore the electrocatalytic properties of Fe x P nanoparticles for the hydrogen evolution reaction (HER) in acidic and neutral electrolytes. In both electrolytes, amorphous FeP is a more efficient catalyst than crystalline FeP, itself more efficient than crystalline Fe 2 P. Our study paves the way for a more systematic investigation of amorphous metal phosphide phases in electrocatalysis. It also shows the beneficial properties of PDF on the characterization of such nanomaterials, which is highly challenging.
Science Advances, 2021
2-Phosphanaphthalenes can be reversibly polymerized to give polycarbophosphanes as a new type of ... more 2-Phosphanaphthalenes can be reversibly polymerized to give polycarbophosphanes as a new type of metal-coordinating polymer.
Angewandte Chemie International Edition, 2021
The cyano(triphenylsilyl)phosphanide anion was prepared as a sodium salt from 2‐phosphaethynolate... more The cyano(triphenylsilyl)phosphanide anion was prepared as a sodium salt from 2‐phosphaethynolate. The electronic structure of this new cyano(silyl)phosphanide was studied via computational methods and its reactivity investigated using various electrophiles and Lewis acids, demonstrating its P‐ and N‐nucleophilicity. The ambident reactivity is in agreement with computations. The silyl group also shows lability and therefore the cyano(silyl)phosphanide can be considered as a phosphacyanamide synthon, [PCN]2−, and serves as building block for the transfer of a PCN moiety.
Dalton Transactions, 2020
Anionic benzo 1,3,4-azadiphopholides can be used for the synthesis of a new family of scorpionate... more Anionic benzo 1,3,4-azadiphopholides can be used for the synthesis of a new family of scorpionate type ligands which allow to prepare multinuclear transition metal complexes.
![Research paper thumbnail of DFT Provides Insight into the Additive-Free Conversion of Aqueous Methanol to Dihydrogen Catalyzed by [Ru(trop2dad)]: Importance of the (Electronic) Flexibility of the Diazadiene Moiety](https://attachments.academia-assets.com/114300308/thumbnails/1.jpg)
](Journal of the American Chemical Society, 2018
The mechanism for complete dehydrogenation of aqueous methanol to CO 2 and three equivalents of H... more The mechanism for complete dehydrogenation of aqueous methanol to CO 2 and three equivalents of H 2 catalyzed by [Ru(trop 2 dad)] was investigated with DFT (trop 2 dad = 1,4-bis(5H-dibenzo[a,d]cyclohepten-5-yl)-1,4-diazabuta-1,3-diene). To date, this is the only catalyst that promotes the acceptorless dehydrogenation of aqueous methanol in homogeneous phase under mild conditions without the addition of an additive (base, acid, or a secondary catalyst). A detailed understanding of the mechanism of this transformation may therefore be of significant importance for the conversion of liquid organic fuels. Previous computational studies using simplified models of the catalyst suggested entirely ligandcentered reaction pathways with rather high-energy barriers for complete dehydrogenation of aqueous methanol. These are, however, not consistent with the experimental data. In the present paper, we reveal a different reaction mechanism for aqueous methanol dehydrogenation that involves metal−ligand cooperativity involving the diazadiene (dad) ligand and has substantially lower barriers, in good agreement with the experimental data. The dad moiety of the ligand actively participates in the alcohol activation mechanism. In the first step of the reaction, the dad ligand rearranges from a σto a π-bound coordination mode. This adjusts the electronic structure of both the metal and the ligand, leading to an enhanced Brønsted basicity of the nitrogen centers and higher Lewis acidity of the ruthenium center. As a result, concerted proton-hydride transfer to/from metal-hydride and N-protonated dad-ligand moieties becomes possible, leading to low-barrier metal−ligand cooperative elementary steps for alcohol activation and H 2 elimination.
Dalton Transactions, 2019
The synthesis and reactivity of salen supported OCP adducts of aluminium and gallium is reported.
Chemical Science, 2019
As compared to the normal η1-P σ-complexes or η6-phosphinine π-complexes, the rare μ2-P bridging ... more As compared to the normal η1-P σ-complexes or η6-phosphinine π-complexes, the rare μ2-P bridging binding mode of phosphinines can be tuned by employing electron donating substitute.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 11, 2018
Coordination of the diazadiene diolefin ligand (trop dad) to ruthenium leads to various complexes... more Coordination of the diazadiene diolefin ligand (trop dad) to ruthenium leads to various complexes of composition [Ru(trop dad)(L)]. DFT studies indicate that the closed-shell singlet (CSS), open-shell singlet (OSS), and triplet electronic structures of this species are close in energy, with the OSS spin configuration being the lowest in energy for all tested functionals. Singlet-state CASSCF calculations revealed a significant multireference character for these complexes. The closed-shell singlet wavefunction dominates, but these complexes have a significant (≈8-16 %) open-shell singlet [d -Ru (L)(trop dad )] contribution mixed into the ground state. In agreement with their ambivalent electronic structure, these complexes reveal both metal- and ligand-centered reactivity. Most notable are the reactions with AdN , diazomethane, and a phosphaalkyne leading to scission of the C-C bond of the diazadiene (dad) moiety of the trop dad ligand, resulting in net (formal) nitrene, carbene, or ...
Angewandte Chemie (International ed. in English), Jan 20, 2017
Cellulose nanocrystals (CNCs) with >2000 photoactive groups can act as highly efficient initia... more Cellulose nanocrystals (CNCs) with >2000 photoactive groups can act as highly efficient initiators for radical polymerizations, cross-linkers, as well as covalently embedded nanofillers for nanocomposite hydrogels. This is achieved by a simple and reliable method for surface modification of CNCs with a photoactive bis(acyl)phosphane oxide derivative. With methacrylates as mono-functional monomers, shape-persistent and free-standing 3D structured objects were printed, showing a superior swelling capacity and improved mechanical properties.
CHIMIA, 2016
The parent phosphinidene–carbene adduct NHC=PH is a versatile synthon in main group chemistry and... more The parent phosphinidene–carbene adduct NHC=PH is a versatile synthon in main group chemistry and can act as an electronically flexible ligand for transition metals. Previously, it could only be synthesized with sterically demanding N-aryl substituents. This paper describes simple methods for the synthesis of NHC=PH adducts with varying steric demand from elemental phosphorus or easily accessible phosphorus sources. Furthermore, the reactivity of NHCs towards PH3 was investigated. It was shown how a NHC inserts into the P–H bond of PH3, which opens up a route to NHC=PH adducts from an imidazolium salt and PH3. The adducts were used in the simple syntheses of bis(phosphinidene) mercury(II) and group 6 pentacarbonyl parent phosphinidene complexes. Their electronic and structural properties were investigated to elucidate the influence of the NHC on the phosphinidene and identify possible applications.
Nature communications, Jan 28, 2017
Small organic molecules provide a promising solution for the requirement to store large amounts o... more Small organic molecules provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. Herein, we report that diolefin-ruthenium complexes containing the chemically and redox non-innocent ligand trop2dad catalyse the production of H2 from formaldehyde and water in the presence of a base. The process involves the catalytic conversion to carbonate salt using aqueous solutions and is the fastest reported for acceptorless formalin dehydrogenation to date. A mechanism supported by density functional theory calculations postulates protonation of a ruthenium hydride to form a low-valent active species, the reversible uptake of dihydrogen by the ligand and active participation of both the ligand and the metal in substrate activation and dihydrogen bond formation.
Chemistry – A European Journal, 2017
A family of cobalt complexes bearing the trop2NH [bis(5‐H‐dibenzo[a,d]cyclohepten‐5‐yl)‐amine] an... more A family of cobalt complexes bearing the trop2NH [bis(5‐H‐dibenzo[a,d]cyclohepten‐5‐yl)‐amine] and 2,2’‐bpy (2,2’‐bipyridine) chelate ligands were prepared and fully characterized. The compounds [Co(trop2N)(bpy)], [Co(trop2NH)(bpy)]+, and [Co(trop2N)(bpy)]+ are cobalt complexes interrelated by one‐electron redox processes and/or proton transfer. Two limiting resonance structures can be used to describe the paramagnetic complex [Co(trop2N)(bpy)]+: [CoII(trop2N−)(bpy)]+ (CoII amido) and [CoI(trop2N⋅)(bpy)]+ (CoI‐aminyl radical). Structural data, DFT calculations, and reactivity toward H‐abstraction indicate a slightly higher contribution of the aminyl radical form to the ground state of [Co(trop2N)(bpy)]+. The results described here complete the series of Group 9 metal aminyl radical complexes bearing the diolefin amine ligand trop2NH.
Chemical Communications, 2016
We report a photo-triggered, two-step fragmentation mechanism generating metaphosphorous acid.
Chemical Communications, 2016
A unique square planar anionic ruthenium(0) complex with amido and amine donors undergoes rapid N... more A unique square planar anionic ruthenium(0) complex with amido and amine donors undergoes rapid NH oxidative addition/elimination reactions.
European Journal of Inorganic Chemistry, 2015
The reaction between the sodium salt of 2‐oxyphosphinine and diphenylchlorophosphine leads to 2‐d... more The reaction between the sodium salt of 2‐oxyphosphinine and diphenylchlorophosphine leads to 2‐diphenylphosphinite phosphinine as a new chelating ligand. Copper(I) complexes are easily and quantitatively obtained when this compound is reacted with CuIX (X = Cl, Br, I). The optical properties of these complexes were investigated; all of them show phosphorescence in the solid state at room temperature and emit orange‐red light in the range 658 to 702 nm with average lifetimes from 19.98 to 25.01 μs. The emission wavelength is tuned by the nature of the halide ligand: Cl–, which leads to a larger ligand‐field splitting, gives the longest emission wavelength, whereas I–, which generates a smaller ligand‐field splitting, leads to the shortest emission wavelength.
Related Article: Tetiana Krachko, Mark Bispinghoff, Aaron M. Tondreau, Daniel Stein, Matthew Bake... more Related Article: Tetiana Krachko, Mark Bispinghoff, Aaron M. Tondreau, Daniel Stein, Matthew Baker, Andreas W. Ehlers, J. Chris Slootweg, Hansjorg Grutzmacher|2017|Angew.Chem.,Int.Ed.|56|7948|doi:10.1002/anie.201703672
Angewandte Chemie, Jul 2, 2010
Scheme 1. Cationic three-membered phosphorus heterocycles (A-C) and BABAR-Phos derivatives D-G. S... more Scheme 1. Cationic three-membered phosphorus heterocycles (A-C) and BABAR-Phos derivatives D-G. Scheme 2. Synthesis of 2 and 3.
Angewandte Chemie
Reaction of the 6π‐electron aromatic four‐membered heterocycle (IPr)2C2P2 (1) (IPr=1,3‐bis(2,6‐di... more Reaction of the 6π‐electron aromatic four‐membered heterocycle (IPr)2C2P2 (1) (IPr=1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐dihydro‐2H‐imidazol‐2‐ylidene) with [Fe2CO9] gives the neutral iron tricarbonyl complex [Fe(CO)3‐η3‐{(IPr)2C2P2}] (2). Oxidation with two equivalents of the ferrocenium salt, [Fe(Cp)2](BArF24), affords the dicationic tricarbonyl complex [Fe(CO)3‐η4‐{(IPr)2C2P2}](BArF24)2 (4). The one‐electron oxidation proceeds under concomitant loss of one CO ligand to give the paramagnetic dicarbonyl radical cation complex [Fe(CO)2‐η4‐{(IPr)2C2P2}](BArF24) (5). Reduction of 5 allows the preparation of the neutral dicarbonyl complex [Fe(CO)2‐η4‐{(IPr)2C2P2}] (6). An analysis by various spectroscopic techniques (57Fe Mössbauer, EPR) combined with DFT calculations gives insight into differences of the electronic structure within the members of this unique series of iron carbonyl complexes, which can be either described as electron precise or Wade–Mingos clusters.
Zeitschrift für anorganische und allgemeine Chemie, 2022
The reaction between [Ru2Cl2(μ2‐Cl)2(CO)6] and the biradicaloid [P(μ‐NTer)]2 proceeds under inser... more The reaction between [Ru2Cl2(μ2‐Cl)2(CO)6] and the biradicaloid [P(μ‐NTer)]2 proceeds under insertion of a Ru(II)Cl(CO)2 fragment into one P−N bond and addition of chloride to the adjacent phosphorus center. Thereby an unprecedented inorganic ruthenacycle is obtained that was investigated by single crystal X‐ray analysis, NMR and IR spectroscopy and DFT calculations. The reactivity of the complex in a halide‐pseudo‐halide exchange reaction and a coordination reaction were investigated.
Dalton Transactions, 2022
This Frontiers article summarizes the reported computational research performed on ruthenium cata... more This Frontiers article summarizes the reported computational research performed on ruthenium catalyzed methanol dehydrogenation reactions performed in the past decade, and serves as a guide for future research.
ChemNanoMat, 2020
The formation of iron phosphide nanoparticles (Fe x P NPs) is a well-studied process. It usually ... more The formation of iron phosphide nanoparticles (Fe x P NPs) is a well-studied process. It usually uses air-sensitive phosphorus precursors such as n-trioctylphosphine or white phosphorus. In this study, we report the synthesis and characterization of a remarkably stable tetrakis(acyl)cyclotetraphosphane, P 4 (MesCO) 4. We demonstrate that this compound can be used as a stoichiometric source of P(0) species in order to synthesize FeP and Fe 2 P nanoparticles at only 250 °C. This tunable process provides a route to monodisperse nanoparticles with different compositions and crystallinities. We combine X-Ray photoelectron spectroscopy (XPS) and atomic pair distribution function (PDF) in order to study the local order and bonding in the amorphous and crystalline materials. We show that crystalline FeP forms via an intermediate amorphous phase (obtained at a lower temperature) that presents local order similar to that of the crystalline sample. From the results of this work, a better understanding of the mechanism of the formation of amorphous and crystalline Fe x P NPs is provided which relies on the use of a stoichiometric and single P-source. We then explore the electrocatalytic properties of Fe x P nanoparticles for the hydrogen evolution reaction (HER) in acidic and neutral electrolytes. In both electrolytes, amorphous FeP is a more efficient catalyst than crystalline FeP, itself more efficient than crystalline Fe 2 P. Our study paves the way for a more systematic investigation of amorphous metal phosphide phases in electrocatalysis. It also shows the beneficial properties of PDF on the characterization of such nanomaterials, which is highly challenging.
Science Advances, 2021
2-Phosphanaphthalenes can be reversibly polymerized to give polycarbophosphanes as a new type of ... more 2-Phosphanaphthalenes can be reversibly polymerized to give polycarbophosphanes as a new type of metal-coordinating polymer.
Angewandte Chemie International Edition, 2021
The cyano(triphenylsilyl)phosphanide anion was prepared as a sodium salt from 2‐phosphaethynolate... more The cyano(triphenylsilyl)phosphanide anion was prepared as a sodium salt from 2‐phosphaethynolate. The electronic structure of this new cyano(silyl)phosphanide was studied via computational methods and its reactivity investigated using various electrophiles and Lewis acids, demonstrating its P‐ and N‐nucleophilicity. The ambident reactivity is in agreement with computations. The silyl group also shows lability and therefore the cyano(silyl)phosphanide can be considered as a phosphacyanamide synthon, [PCN]2−, and serves as building block for the transfer of a PCN moiety.
Dalton Transactions, 2020
Anionic benzo 1,3,4-azadiphopholides can be used for the synthesis of a new family of scorpionate... more Anionic benzo 1,3,4-azadiphopholides can be used for the synthesis of a new family of scorpionate type ligands which allow to prepare multinuclear transition metal complexes.
Journal of the American Chemical Society, 2018
The mechanism for complete dehydrogenation of aqueous methanol to CO 2 and three equivalents of H... more The mechanism for complete dehydrogenation of aqueous methanol to CO 2 and three equivalents of H 2 catalyzed by [Ru(trop 2 dad)] was investigated with DFT (trop 2 dad = 1,4-bis(5H-dibenzo[a,d]cyclohepten-5-yl)-1,4-diazabuta-1,3-diene). To date, this is the only catalyst that promotes the acceptorless dehydrogenation of aqueous methanol in homogeneous phase under mild conditions without the addition of an additive (base, acid, or a secondary catalyst). A detailed understanding of the mechanism of this transformation may therefore be of significant importance for the conversion of liquid organic fuels. Previous computational studies using simplified models of the catalyst suggested entirely ligandcentered reaction pathways with rather high-energy barriers for complete dehydrogenation of aqueous methanol. These are, however, not consistent with the experimental data. In the present paper, we reveal a different reaction mechanism for aqueous methanol dehydrogenation that involves metal−ligand cooperativity involving the diazadiene (dad) ligand and has substantially lower barriers, in good agreement with the experimental data. The dad moiety of the ligand actively participates in the alcohol activation mechanism. In the first step of the reaction, the dad ligand rearranges from a σto a π-bound coordination mode. This adjusts the electronic structure of both the metal and the ligand, leading to an enhanced Brønsted basicity of the nitrogen centers and higher Lewis acidity of the ruthenium center. As a result, concerted proton-hydride transfer to/from metal-hydride and N-protonated dad-ligand moieties becomes possible, leading to low-barrier metal−ligand cooperative elementary steps for alcohol activation and H 2 elimination.
Dalton Transactions, 2019
The synthesis and reactivity of salen supported OCP adducts of aluminium and gallium is reported.
Chemical Science, 2019
As compared to the normal η1-P σ-complexes or η6-phosphinine π-complexes, the rare μ2-P bridging ... more As compared to the normal η1-P σ-complexes or η6-phosphinine π-complexes, the rare μ2-P bridging binding mode of phosphinines can be tuned by employing electron donating substitute.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 11, 2018
Coordination of the diazadiene diolefin ligand (trop dad) to ruthenium leads to various complexes... more Coordination of the diazadiene diolefin ligand (trop dad) to ruthenium leads to various complexes of composition [Ru(trop dad)(L)]. DFT studies indicate that the closed-shell singlet (CSS), open-shell singlet (OSS), and triplet electronic structures of this species are close in energy, with the OSS spin configuration being the lowest in energy for all tested functionals. Singlet-state CASSCF calculations revealed a significant multireference character for these complexes. The closed-shell singlet wavefunction dominates, but these complexes have a significant (≈8-16 %) open-shell singlet [d -Ru (L)(trop dad )] contribution mixed into the ground state. In agreement with their ambivalent electronic structure, these complexes reveal both metal- and ligand-centered reactivity. Most notable are the reactions with AdN , diazomethane, and a phosphaalkyne leading to scission of the C-C bond of the diazadiene (dad) moiety of the trop dad ligand, resulting in net (formal) nitrene, carbene, or ...
Angewandte Chemie (International ed. in English), Jan 20, 2017
Cellulose nanocrystals (CNCs) with >2000 photoactive groups can act as highly efficient initia... more Cellulose nanocrystals (CNCs) with >2000 photoactive groups can act as highly efficient initiators for radical polymerizations, cross-linkers, as well as covalently embedded nanofillers for nanocomposite hydrogels. This is achieved by a simple and reliable method for surface modification of CNCs with a photoactive bis(acyl)phosphane oxide derivative. With methacrylates as mono-functional monomers, shape-persistent and free-standing 3D structured objects were printed, showing a superior swelling capacity and improved mechanical properties.
CHIMIA, 2016
The parent phosphinidene–carbene adduct NHC=PH is a versatile synthon in main group chemistry and... more The parent phosphinidene–carbene adduct NHC=PH is a versatile synthon in main group chemistry and can act as an electronically flexible ligand for transition metals. Previously, it could only be synthesized with sterically demanding N-aryl substituents. This paper describes simple methods for the synthesis of NHC=PH adducts with varying steric demand from elemental phosphorus or easily accessible phosphorus sources. Furthermore, the reactivity of NHCs towards PH3 was investigated. It was shown how a NHC inserts into the P–H bond of PH3, which opens up a route to NHC=PH adducts from an imidazolium salt and PH3. The adducts were used in the simple syntheses of bis(phosphinidene) mercury(II) and group 6 pentacarbonyl parent phosphinidene complexes. Their electronic and structural properties were investigated to elucidate the influence of the NHC on the phosphinidene and identify possible applications.
Nature communications, Jan 28, 2017
Small organic molecules provide a promising solution for the requirement to store large amounts o... more Small organic molecules provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. Herein, we report that diolefin-ruthenium complexes containing the chemically and redox non-innocent ligand trop2dad catalyse the production of H2 from formaldehyde and water in the presence of a base. The process involves the catalytic conversion to carbonate salt using aqueous solutions and is the fastest reported for acceptorless formalin dehydrogenation to date. A mechanism supported by density functional theory calculations postulates protonation of a ruthenium hydride to form a low-valent active species, the reversible uptake of dihydrogen by the ligand and active participation of both the ligand and the metal in substrate activation and dihydrogen bond formation.
Chemistry – A European Journal, 2017
A family of cobalt complexes bearing the trop2NH [bis(5‐H‐dibenzo[a,d]cyclohepten‐5‐yl)‐amine] an... more A family of cobalt complexes bearing the trop2NH [bis(5‐H‐dibenzo[a,d]cyclohepten‐5‐yl)‐amine] and 2,2’‐bpy (2,2’‐bipyridine) chelate ligands were prepared and fully characterized. The compounds [Co(trop2N)(bpy)], [Co(trop2NH)(bpy)]+, and [Co(trop2N)(bpy)]+ are cobalt complexes interrelated by one‐electron redox processes and/or proton transfer. Two limiting resonance structures can be used to describe the paramagnetic complex [Co(trop2N)(bpy)]+: [CoII(trop2N−)(bpy)]+ (CoII amido) and [CoI(trop2N⋅)(bpy)]+ (CoI‐aminyl radical). Structural data, DFT calculations, and reactivity toward H‐abstraction indicate a slightly higher contribution of the aminyl radical form to the ground state of [Co(trop2N)(bpy)]+. The results described here complete the series of Group 9 metal aminyl radical complexes bearing the diolefin amine ligand trop2NH.
Chemical Communications, 2016
We report a photo-triggered, two-step fragmentation mechanism generating metaphosphorous acid.
Chemical Communications, 2016
A unique square planar anionic ruthenium(0) complex with amido and amine donors undergoes rapid N... more A unique square planar anionic ruthenium(0) complex with amido and amine donors undergoes rapid NH oxidative addition/elimination reactions.
European Journal of Inorganic Chemistry, 2015
The reaction between the sodium salt of 2‐oxyphosphinine and diphenylchlorophosphine leads to 2‐d... more The reaction between the sodium salt of 2‐oxyphosphinine and diphenylchlorophosphine leads to 2‐diphenylphosphinite phosphinine as a new chelating ligand. Copper(I) complexes are easily and quantitatively obtained when this compound is reacted with CuIX (X = Cl, Br, I). The optical properties of these complexes were investigated; all of them show phosphorescence in the solid state at room temperature and emit orange‐red light in the range 658 to 702 nm with average lifetimes from 19.98 to 25.01 μs. The emission wavelength is tuned by the nature of the halide ligand: Cl–, which leads to a larger ligand‐field splitting, gives the longest emission wavelength, whereas I–, which generates a smaller ligand‐field splitting, leads to the shortest emission wavelength.