The σ-arsolido complex [Mo(AsC4Me4)(CO)3(η5-C5H5)] is alkylated at arsenic by MeOTf to afford the pentamethylarsole complex [Mo(MeAsC4Me4)(CO)3(η5-C5H5)](OTf) while iodomethane affords a mixture of [Me2AsC4Me4]I, [MoMe(CO)3(η5-C5H5)], [MoI(CO)3(η5-C5H5)] and the arsole complexes cisoid- and transoid-[MoI(MeAsC4Me4)(CO)2(η5-C5H5)] and transoid-[Mo{C(O)Me}(MeAsC4Me4)(CO)2(η5-C5H5)], The arsole ligand in [Mo(MeAsC4Me4)(CO)3(η5-C5H5)](OTf) is readily liberated by NaI in acetone to afford free MeAsC4Me4 and [MoI(CO)3(η5-C5H5)]. In a similar manner, the reaction of [Mo(AsC4Ph4)(CO)3(η5-C5H5)] with MeI affords MeAsC4Ph4 and [MoI(CO)3(η5-C5H5)], while [Mo{AsC4(SiMe3)-2-Me2-3,4}(CO)3(η5-C5H5)] with MeOTf affords [Mo{MeAsC4(SiMe3)-2-Me2-3,4}(CO)3(η5-C5H5)](OTf). The reaction of [Mo(AsC4Me4)(CO)3(η5-C5H5)] with activated alkynes (RCCR: R = CF3, CO2Me) does not proceed via [4 + 2] cyclo-addition but rather electrophilic attack at arsenic followed by metallacyclisation with incorporation of a carbonyl ligand in the spirocyclic complexes [Mo{As(C4Me4)CRCRCO}(CO)2(η5-C5H5)].
σ-胂络合物[Mo(AsC4Me4)(CO)3(η5-C5H5)]被 MeOTf 在砷处烷基化，得到五甲基胂络合物[Mo(MeAsC4Me4)(CO)3(η5-C5H5)](OTf)，而碘甲烷得到[Me2AsC4Me4]I、[MoMe(CO)3(η5-C5H5)]的混合物、[MoI(CO)3(η5-C5H5)]以及顺式和反式[MoI(MeAsC4Me4)(CO)2(η5-C5H5)]和反式[Mo{C(O)Me}(MeAsC4Me4)(CO)2(η5-C5H5)]的芳基络合物、Mo(MeAsC4Me4)(CO)3(η5-C5H5)](OTf)中的芳基配体很容易被丙酮中的 NaI 解离，从而得到游离的 MeAsC4Me4 和 [MoI(CO)3(η5-C5H5)]。类似地，[Mo(AsC4Ph4)(CO)3(η5-C5H5)] 与 MeI 反应生成 MeAsC4Ph4 和 [MoI(CO)3(η5-C5H5)]、而[Mo{AsC4(SiMe3)-2-Me2-3,4}(CO)3(η5-C5H5)]与 MeOTf 反应生成[Mo{MeAsC4(SiMe3)-2-Me2-3,4}(CO)3(η5-C5H5)](OTf)。Mo(AsC4Me4)(CO)3(η5-C5H5)]与活化炔（RCCR：R = CF3，CO2Me）的反应不是通过[4 + 2]环加成进行的，而是在砷处发生亲电攻击，然后在螺环配合物[Mo{As(C4Me4)CRCRCO}(CO)2(η5-C5H5)]中加入羰基配体进行金属化。
{"title":"Electrophilic As-functionalisation of σ-arsolido complexes.","authors":"Ryan M Kirk, Anthony F Hill","doi":"10.1039/d4dt01371a","DOIUrl":"https://doi.org/10.1039/d4dt01371a","url":null,"abstract":"<p><p>The σ-arsolido complex [Mo(AsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] is alkylated at arsenic by MeOTf to afford the pentamethylarsole complex [Mo(MeAsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)](OTf) while iodomethane affords a mixture of [Me<sub>2</sub>AsC<sub>4</sub>Me<sub>4</sub>]I, [MoMe(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)], [MoI(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] and the arsole complexes <i>cisoid</i>- and <i>transoid</i>-[MoI(MeAsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>2</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] and <i>transoid</i>-[Mo{C(O)Me}(MeAsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>2</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)], The arsole ligand in [Mo(MeAsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)](OTf) is readily liberated by NaI in acetone to afford free MeAsC<sub>4</sub>Me<sub>4</sub> and [MoI(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)]. In a similar manner, the reaction of [Mo(AsC<sub>4</sub>Ph<sub>4</sub>)(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] with MeI affords MeAsC<sub>4</sub>Ph<sub>4</sub> and [MoI(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)], while [Mo{AsC<sub>4</sub>(SiMe<sub>3</sub>)-2-Me<sub>2</sub>-3,4}(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] with MeOTf affords [Mo{MeAsC<sub>4</sub>(SiMe<sub>3</sub>)-2-Me<sub>2</sub>-3,4}(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)](OTf). The reaction of [Mo(AsC<sub>4</sub>Me<sub>4</sub>)(CO)<sub>3</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)] with activated alkynes (RCCR: R = CF<sub>3</sub>, CO<sub>2</sub>Me) does not proceed <i>via</i> [4 + 2] <i>cyclo</i>-addition but rather electrophilic attack at arsenic followed by metallacyclisation with incorporation of a carbonyl ligand in the spirocyclic complexes [Mo{As(C<sub>4</sub>Me<sub>4</sub>)CRCRCO}(CO)<sub>2</sub>(η<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)].</p>","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141490040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vladimir Arion, Iuliana Besleaga, Renata Raptova, Alexandru-Constantin Stoica, Miljan N.M. Milunović, Michal Zalibera, Ruoli Bai, Nora Igaz, Johannes Reynisson, Monika Kiricsi, Eva A. Enyedy, P. Rapta, Ernest Hamel
Quite recently we discovered that copper(II) complexes with isomeric morpholine-thiosemicarbazone (morph-TSCs) hybrid ligands show good cytotoxicity in cancer cells and that the molecular target responsible for this activity might be tubulin. In order to obtain better lead drug candidates, we opted to exploit the power of coordination chemistry to (i) assemble structures with globular shape to better fit the colchicine pocket and (ii) vary the metal ion. We report the synthesis and full characterization of bis-ligand cobalt(III) and iron(III) complexes with 6-morpholinomethyl-2-formylpyridine 4N-(4-hydroxy-3,5-dimethylphenyl)-3-thiosemicarbazone (HL1), 6-morpholinomethyl-2-acetylpyridine 4N-(4-hydroxy-3,5-dimethylphenyl)-3-thiosemicarbazone (HL2), and 6-morpholinomethyl-2-formylpyridine 4N-phenyl-3-thiosemicarbazone (HL3), and mono-ligand nickel(II), zinc(II) and palladium(II) complexes with HL1, namely [CoIII(HL1)(L1)](NO3)2 (1), [CoIII(HL2)(L2)](NO3)2 (2), [CoIII(HL3)(L3)](NO3)2 (3), [FeIII(L2)2]NO3 (4), [FeIII(HL3)(L3)](NO3)2 (5), [NiII(L1)]Cl (6), [Zn(L1)Cl] (7) and [PdII(HL1)Cl]Cl (8). We discuss the effect of the metal identity and metal complex stoichiometry on in vitro cytotoxicity and antitubulin activity. The high antiproliferative activity of complex 4 correlated well with inhibition of tubulin polymerization. Insights into the mechanism of antiproliferative activity were supported by experimental results and molecular docking calculations.
{"title":"Are the metal identity and stoichiometry of metal complexes important for colchicine site binding and inhibition of tubulin polymerization?","authors":"Vladimir Arion, Iuliana Besleaga, Renata Raptova, Alexandru-Constantin Stoica, Miljan N.M. Milunović, Michal Zalibera, Ruoli Bai, Nora Igaz, Johannes Reynisson, Monika Kiricsi, Eva A. Enyedy, P. Rapta, Ernest Hamel","doi":"10.1039/d4dt01469c","DOIUrl":"https://doi.org/10.1039/d4dt01469c","url":null,"abstract":"Quite recently we discovered that copper(II) complexes with isomeric morpholine-thiosemicarbazone (morph-TSCs) hybrid ligands show good cytotoxicity in cancer cells and that the molecular target responsible for this activity might be tubulin. In order to obtain better lead drug candidates, we opted to exploit the power of coordination chemistry to (i) assemble structures with globular shape to better fit the colchicine pocket and (ii) vary the metal ion. We report the synthesis and full characterization of bis-ligand cobalt(III) and iron(III) complexes with 6-morpholinomethyl-2-formylpyridine 4N-(4-hydroxy-3,5-dimethylphenyl)-3-thiosemicarbazone (HL1), 6-morpholinomethyl-2-acetylpyridine 4N-(4-hydroxy-3,5-dimethylphenyl)-3-thiosemicarbazone (HL2), and 6-morpholinomethyl-2-formylpyridine 4N-phenyl-3-thiosemicarbazone (HL3), and mono-ligand nickel(II), zinc(II) and palladium(II) complexes with HL1, namely [CoIII(HL1)(L1)](NO3)2 (1), [CoIII(HL2)(L2)](NO3)2 (2), [CoIII(HL3)(L3)](NO3)2 (3), [FeIII(L2)2]NO3 (4), [FeIII(HL3)(L3)](NO3)2 (5), [NiII(L1)]Cl (6), [Zn(L1)Cl] (7) and [PdII(HL1)Cl]Cl (8). We discuss the effect of the metal identity and metal complex stoichiometry on in vitro cytotoxicity and antitubulin activity. The high antiproliferative activity of complex 4 correlated well with inhibition of tubulin polymerization. Insights into the mechanism of antiproliferative activity were supported by experimental results and molecular docking calculations.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peng Chen, Qianju Song, Can Ma, Zao Yi, Liang Bian, Shubo Cheng, Zhiqiang hao, Tangyou Sun, Pinghui Wu, Qingdong Zeng
Currently, the application field of sunlight is huge, but the absorption efficiency of solar absorbers for sunlight still needs to be improved. In this paper, we design a solar absorber structure consisting of five cycles of stacked absorber units, where a single absorber unit is a cell consisting of a three-layer SiO2-InAs-TiN film. By stacking the first layer of absorber units on the refractory metal W of the substrate, the subsequent four absorber units reduce the cycles regularly and are stacked sequentially according to our optimized value of 50 nm, and such a design enhances the SPR at the corners of each absorber unit and the Fabry-Perot resonance coupling between absorber units, ultimately achieving the perfect absorption of the absorber in the bandwidth of 2599.5 nm. It is noteworthy that there is an ultra-perfect absorption (A>99%) in the band of 2001 nm. After the finite difference time domain method in time domain (FDTD) calculation, its weighted average absorption (AM1.5) is 99.31%. At 1000 K and 1200 K, the thermal radiation efficiency is 97.35% and 97.83%, respectively. Meanwhile, the structure of the absorber is independent of polarization, and the sun's incidence angle has increased to 60°, but it still achieves an average absorption of 90.83% over the whole wavelength band (280 to 3000 nm). It is worth noting that the innovation of our work lies in the design of a multilayer recycled absorber unit structure, which can efficiently maintain the absorber's absorption bandwidth in the visible-near-infrared wavelength band, and its strong thermal radiation efficiency can also be applied in the field of thermal emitters.
目前，太阳光的应用领域非常广泛，但太阳能吸收器对太阳光的吸收效率仍有待提高。本文设计了一种由五个循环堆叠吸收单元组成的太阳能吸收器结构，其中单个吸收单元是由三层 SiO2-InAs-TiN 薄膜组成的单元。通过在基底的难熔金属 W 上堆叠第一层吸收单元，随后的四个吸收单元有规律地减少循环，并按照我们的优化值 50 nm 依次堆叠，这样的设计增强了每个吸收单元边角的 SPR 以及吸收单元之间的法布里-珀罗共振耦合，最终实现了吸收器在 2599.5 nm 带宽内的完美吸收。值得注意的是，2001 nm 波段的吸收率超完美（A>99%）。经过有限差分时域法（FDTD）计算，其加权平均吸收率（AM1.5）为 99.31%。在 1000 K 和 1200 K 时，热辐射效率分别为 97.35% 和 97.83%。同时，吸收器的结构与偏振无关，太阳入射角也增加到了 60°，但它在整个波段（280 纳米到 3000 纳米）的平均吸收率仍然达到了 90.83%。值得注意的是，我们工作的创新之处在于设计了一种多层循环吸收器单元结构，它能有效地保持吸收器在可见光-近红外波段的吸收带宽，其较强的热辐射效率也可应用于热辐射器领域。
{"title":"Multilayer stacked ultra-wideband perfect solar absorber and thermal emitter based on SiO2-InAs-TiN nanofilm structure","authors":"Peng Chen, Qianju Song, Can Ma, Zao Yi, Liang Bian, Shubo Cheng, Zhiqiang hao, Tangyou Sun, Pinghui Wu, Qingdong Zeng","doi":"10.1039/d4dt01626b","DOIUrl":"https://doi.org/10.1039/d4dt01626b","url":null,"abstract":"Currently, the application field of sunlight is huge, but the absorption efficiency of solar absorbers for sunlight still needs to be improved. In this paper, we design a solar absorber structure consisting of five cycles of stacked absorber units, where a single absorber unit is a cell consisting of a three-layer SiO2-InAs-TiN film. By stacking the first layer of absorber units on the refractory metal W of the substrate, the subsequent four absorber units reduce the cycles regularly and are stacked sequentially according to our optimized value of 50 nm, and such a design enhances the SPR at the corners of each absorber unit and the Fabry-Perot resonance coupling between absorber units, ultimately achieving the perfect absorption of the absorber in the bandwidth of 2599.5 nm. It is noteworthy that there is an ultra-perfect absorption (A>99%) in the band of 2001 nm. After the finite difference time domain method in time domain (FDTD) calculation, its weighted average absorption (AM1.5) is 99.31%. At 1000 K and 1200 K, the thermal radiation efficiency is 97.35% and 97.83%, respectively. Meanwhile, the structure of the absorber is independent of polarization, and the sun's incidence angle has increased to 60°, but it still achieves an average absorption of 90.83% over the whole wavelength band (280 to 3000 nm). It is worth noting that the innovation of our work lies in the design of a multilayer recycled absorber unit structure, which can efficiently maintain the absorber's absorption bandwidth in the visible-near-infrared wavelength band, and its strong thermal radiation efficiency can also be applied in the field of thermal emitters.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The use of metal catalysts to accelerate an organic transformation has proven indispensable for access to structural motifs having applications across medicinal, polymer, materials chemistry, and more. Most catalytic approaches have cast transition metals as the “leading role”; these players mediate important reactions such as C-C cross coupling and the hydrogenation of unsaturated bonds. These catalysts may require collaboration, featuring Lewis acidic or basic additives to promote a desired reaction outcome. Lewis acids can serve to accelerate reactions by way of substrate stabilization and/or activation, and as such, are valuable in optimizing catalytic transformations. A burgeoning area of chemical research which unifies these concepts has thus sought to develop transition metal complexes having ambiphilic (containing a Lewis basic and acidic unit) ligands. This approach takes advantage of metal-ligand cooperativity to increase the efficiency of a given chemical transformation, leveraging intramolecular interactions between a transition metal and an adjacent secondary ligand site. While this has shown significant potential to facilitate challenging and important transformations, there remains unexplored depth for creativity and future advancement. This Frontier highlights inter- and intramolecular combinations of transition metals and Lewis acids that together, provide a collaborative platform for chemical synthesis.
{"title":"A Catalytic Collaboration: Pairing Transition Metals and Lewis Acids for Applications in Organic Synthesis","authors":"A. Dina Dilinaer, Gabriel Jobin, Marcus W. Drover","doi":"10.1039/d4dt01550a","DOIUrl":"https://doi.org/10.1039/d4dt01550a","url":null,"abstract":"The use of metal catalysts to accelerate an organic transformation has proven indispensable for access to structural motifs having applications across medicinal, polymer, materials chemistry, and more. Most catalytic approaches have cast transition metals as the “leading role”; these players mediate important reactions such as C-C cross coupling and the hydrogenation of unsaturated bonds. These catalysts may require collaboration, featuring Lewis acidic or basic additives to promote a desired reaction outcome. Lewis acids can serve to accelerate reactions by way of substrate stabilization and/or activation, and as such, are valuable in optimizing catalytic transformations. A burgeoning area of chemical research which unifies these concepts has thus sought to develop transition metal complexes having ambiphilic (containing a Lewis basic and acidic unit) ligands. This approach takes advantage of metal-ligand cooperativity to increase the efficiency of a given chemical transformation, leveraging intramolecular interactions between a transition metal and an adjacent secondary ligand site. While this has shown significant potential to facilitate challenging and important transformations, there remains unexplored depth for creativity and future advancement. This Frontier highlights inter- and intramolecular combinations of transition metals and Lewis acids that together, provide a collaborative platform for chemical synthesis.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Irene Bonastre-Sabater, Alberto Lopera, Álvaro Martínez-Camarena, Salvador Blasco, Antonio Doménech-Carbó, Hermas Jimenez, Begoña Verdejo, Enrique García-España, Maria Paz Clares
The Cu2+ complexes of three [1+1] azacyclophane macrocycles having the 1H-pyrazole ring as spacer and the pentaamine 1,5,8,11,15-pentaazadecane (L1) or the hexaamines 1,5,8,12,15,19-hexaazanonadecane (L2) and 1,5,9,13,17,21-hexaazaheneicosane (L3) as bridges show endo coordination of the pyrazolate bridge giving rise to discrete monomeric species. Previously reported pyrazolacyclophanes evidenced, however, exo-coordination with formation of dimeric species of 2:2, 3:2 or even 4:2 Cu2+:L stoichiometry. The complexes have been characterized in solution using potentiometric studies, UV-Vis spectroscopy, paramagnetic NMR, cyclic voltammetry and mass spectrometry. The measurements show that all three ligands have as many protonation steps in water as secondary amines are in the bridge, while they are able to form both mono- and binuclear Cu2+ species. The crystal structures of the complexes [Cu(HL1)Br]Br(1+x)(ClO4)(1-x)·yH2O (1) and [Cu2(H-1L2)Cl(ClO4)](ClO4)·H2O·C2H5OH (2) have been solved by X-ray diffraction studies. In 1 the metal ion lies at one side of the macrocyclic cavity being coordinated by one nitrogen of the pyrazolate moiety and the three consecutive nitrogen atoms of the polyamine bridge. The other nitrogen of the pyrazole ring is hydrogen-bonded to an amine group. In 2 the two metal ions are interconnected by a pyrazolate bis(monodentate) moiety and complete their coordination spheres with three amines and either a bromide or a perchlorate anion, which occupy the axial positions of distorted square pyramid geometries. Paramagnetic NMR studies of the binuclear complexes confirm the coordination pattern observed in the crystal structures. Cyclic voltamperommetry data show potentials within the adequate range to exhibit superoxide dismutase (SOD) activity. The IC50 values calculated by McCord-Fridovich enzymatic assays show that the binuclear Cu2+ complexes of L2 and L3 have SOD activities that rank amongst the highest ones so far reported
{"title":"Exo- or Endo- 1H-Pyrazole Metal Coordination Modulated by Polyamine Chain length in [1+1] Condensation Azamacrocycles. Binuclear Complexes with Remarkable SOD activity","authors":"Irene Bonastre-Sabater, Alberto Lopera, Álvaro Martínez-Camarena, Salvador Blasco, Antonio Doménech-Carbó, Hermas Jimenez, Begoña Verdejo, Enrique García-España, Maria Paz Clares","doi":"10.1039/d4dt01236d","DOIUrl":"https://doi.org/10.1039/d4dt01236d","url":null,"abstract":"The Cu2+ complexes of three [1+1] azacyclophane macrocycles having the 1H-pyrazole ring as spacer and the pentaamine 1,5,8,11,15-pentaazadecane (L1) or the hexaamines 1,5,8,12,15,19-hexaazanonadecane (L2) and 1,5,9,13,17,21-hexaazaheneicosane (L3) as bridges show endo coordination of the pyrazolate bridge giving rise to discrete monomeric species. Previously reported pyrazolacyclophanes evidenced, however, exo-coordination with formation of dimeric species of 2:2, 3:2 or even 4:2 Cu2+:L stoichiometry. The complexes have been characterized in solution using potentiometric studies, UV-Vis spectroscopy, paramagnetic NMR, cyclic voltammetry and mass spectrometry. The measurements show that all three ligands have as many protonation steps in water as secondary amines are in the bridge, while they are able to form both mono- and binuclear Cu2+ species. The crystal structures of the complexes [Cu(HL1)Br]Br(1+x)(ClO4)(1-x)·yH2O (1) and [Cu2(H-1L2)Cl(ClO4)](ClO4)·H2O·C2H5OH (2) have been solved by X-ray diffraction studies. In 1 the metal ion lies at one side of the macrocyclic cavity being coordinated by one nitrogen of the pyrazolate moiety and the three consecutive nitrogen atoms of the polyamine bridge. The other nitrogen of the pyrazole ring is hydrogen-bonded to an amine group. In 2 the two metal ions are interconnected by a pyrazolate bis(monodentate) moiety and complete their coordination spheres with three amines and either a bromide or a perchlorate anion, which occupy the axial positions of distorted square pyramid geometries. Paramagnetic NMR studies of the binuclear complexes confirm the coordination pattern observed in the crystal structures. Cyclic voltamperommetry data show potentials within the adequate range to exhibit superoxide dismutase (SOD) activity. The IC50 values calculated by McCord-Fridovich enzymatic assays show that the binuclear Cu2+ complexes of L2 and L3 have SOD activities that rank amongst the highest ones so far reported","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antimicrobial peptides are promising alternatives to classical antibiotics. Their microbicidal activity can arise from different mechanisms, one of which is known as nutritional immunity and has metal micronutrients and metal-binding biomolecules as its main players. Calcitermin is an antimicrobial peptide and an effective metal-chelator. Its properties as antibacterial and anti-Candida agent have been recently studied both as free peptide and in presence of zinc and copper ions, with which it forms stable complexes. Calcitermin derivatives have also gained attractiveness thanks to the possibility of improving their properties, like metal-binding affinity and/or stability in biological fluids, through ad-hoc modifications of the native peptide sequence. In this work, the Ala-to-Ser substitutions close to the coordination site of calcitermin have been introduced to study the impact on the biological activity and metal-binding properties. Our results show that the metal coordination has a clear impact on the bioactivity of the studied compounds, to the point that also the truncated fragment of calcitermin, solely containing the main metal-binding residues, shows antimicrobial activity.
{"title":"Metal coordination governs the antimicrobial efficacy of calcitermin derivatives","authors":"Silvia Leveraro, Kinga Garstka, Paulina Śliwka, Tomasz Janek, Magdalena Rowińska-Żyrek, Maurizio Remelli, Denise Bellotti","doi":"10.1039/d4dt01514b","DOIUrl":"https://doi.org/10.1039/d4dt01514b","url":null,"abstract":"Antimicrobial peptides are promising alternatives to classical antibiotics. Their microbicidal activity can arise from different mechanisms, one of which is known as nutritional immunity and has metal micronutrients and metal-binding biomolecules as its main players. Calcitermin is an antimicrobial peptide and an effective metal-chelator. Its properties as antibacterial and anti-Candida agent have been recently studied both as free peptide and in presence of zinc and copper ions, with which it forms stable complexes. Calcitermin derivatives have also gained attractiveness thanks to the possibility of improving their properties, like metal-binding affinity and/or stability in biological fluids, through ad-hoc modifications of the native peptide sequence. In this work, the Ala-to-Ser substitutions close to the coordination site of calcitermin have been introduced to study the impact on the biological activity and metal-binding properties. Our results show that the metal coordination has a clear impact on the bioactivity of the studied compounds, to the point that also the truncated fragment of calcitermin, solely containing the main metal-binding residues, shows antimicrobial activity.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yedluri Anil Kumar, Nipa Roy, Tholkappiyan Ramachandran, Mohammed A Assiri, Sunkara Srinivasa Rao, Md Moniruzzaman, Sang Woo Joo
Due to their distinctive security characteristics, all-solid-state batteries are seen as a potential technology for the upcoming era of energy storage. The flexibility of nanomaterials shows enormous potential for the advancement of all-solid-state batteries' exceptional power and energy storage capacities. These batteries might be applied in many areas such as large-scale energy storage for power grids, as well as in the creation of foldable and flexible electronics, and portable gadgets. The most difficult aspect of creating a comprehensive nanoscale all-solid-state battery assembly is the task of decreasing the particle size of the solid electrolyte while maintaining its excellent ionic conductivity. Materials possessing nanoscale structural features and a substantial electrochemically active surface area have the potential to significantly enhance power characteristics and the cycle life. This might bring about substantial changes to existing energy storage models. The primary objective of this research is to summarize the latest advancements in utilizing nanomaterials for energy harvesting in various all-solid-state battery assemblies. This study examines the most complex solid-solid interfaces of all-solid-state batteries, as well as feasible methods for implementing nanomaterials in such interfaces. Currently, there is significant attention on the necessity to develop electrode-solid electrolyte interfaces that exhibit nanoscale particle articulation and other characteristics related to the behavior of lithium ions.
{"title":"Revolutionizing energy storage: exploring the nanoscale frontier of all-solid-state batteries.","authors":"Yedluri Anil Kumar, Nipa Roy, Tholkappiyan Ramachandran, Mohammed A Assiri, Sunkara Srinivasa Rao, Md Moniruzzaman, Sang Woo Joo","doi":"10.1039/d4dt01133c","DOIUrl":"https://doi.org/10.1039/d4dt01133c","url":null,"abstract":"<p><p>Due to their distinctive security characteristics, all-solid-state batteries are seen as a potential technology for the upcoming era of energy storage. The flexibility of nanomaterials shows enormous potential for the advancement of all-solid-state batteries' exceptional power and energy storage capacities. These batteries might be applied in many areas such as large-scale energy storage for power grids, as well as in the creation of foldable and flexible electronics, and portable gadgets. The most difficult aspect of creating a comprehensive nanoscale all-solid-state battery assembly is the task of decreasing the particle size of the solid electrolyte while maintaining its excellent ionic conductivity. Materials possessing nanoscale structural features and a substantial electrochemically active surface area have the potential to significantly enhance power characteristics and the cycle life. This might bring about substantial changes to existing energy storage models. The primary objective of this research is to summarize the latest advancements in utilizing nanomaterials for energy harvesting in various all-solid-state battery assemblies. This study examines the most complex solid-solid interfaces of all-solid-state batteries, as well as feasible methods for implementing nanomaterials in such interfaces. Currently, there is significant attention on the necessity to develop electrode-solid electrolyte interfaces that exhibit nanoscale particle articulation and other characteristics related to the behavior of lithium ions.</p>","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maurice Franke, Tobin Ens, Andreas Mix, Beate Neumann, Georg Stammler, Norbert Werner Mitzel
Flexible poly-Lewis acids (PLA) based on the tribenzotriquinacene (TBTQ) scaffold have been synthesised. Hydrosilylation of 4b,8b,12b-triallyltribenzotriquinacene and subsequent exchange of the chlorine substituents with weaker coordinating triflate groups afforded a novel triple silyl-functionalised PLA. By regioselective hydroboration of triallyl-TBTQ with various organoboranes, PLAs with different Lewis acidities were obtained. The synthesised PLAs were combined with neutral bases in host-guest experiments. DOSY NMR spectroscopy was performed to elucidate the complexation process in solution. These experiments revealed a highly dynamic interaction between the boron-functionalised PLA and triazine. However, the addition of one equivalent of tris(dimethylphosphino(methyl))phenylsilane led to the formation of a 1:1 adduct, which was confirmed by diffusion experiments.
{"title":"Host-guest chemistry of tridentate Lewis acids based on tribenzotriquinacene","authors":"Maurice Franke, Tobin Ens, Andreas Mix, Beate Neumann, Georg Stammler, Norbert Werner Mitzel","doi":"10.1039/d4dt01558d","DOIUrl":"https://doi.org/10.1039/d4dt01558d","url":null,"abstract":"Flexible poly-Lewis acids (PLA) based on the tribenzotriquinacene (TBTQ) scaffold have been synthesised. Hydrosilylation of 4b,8b,12b-triallyltribenzotriquinacene and subsequent exchange of the chlorine substituents with weaker coordinating triflate groups afforded a novel triple silyl-functionalised PLA. By regioselective hydroboration of triallyl-TBTQ with various organoboranes, PLAs with different Lewis acidities were obtained. The synthesised PLAs were combined with neutral bases in host-guest experiments. DOSY NMR spectroscopy was performed to elucidate the complexation process in solution. These experiments revealed a highly dynamic interaction between the boron-functionalised PLA and triazine. However, the addition of one equivalent of tris(dimethylphosphino(methyl))phenylsilane led to the formation of a 1:1 adduct, which was confirmed by diffusion experiments.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oier Pajuelo-Corral, Inmaculada Ortiz-Gomez, Jose Angel Garcia, Antonio Rodríguez Diéguez, Iñigo J. Vitorica Yrezabal, Alfonso Salinas-Castillo, José M. Seco, Javier Cepeda
In this work, we report on five novel coordination polymers (CPs) based on the linkage of the [Cd(6apic)2] building block [where 6apic = 6-aminopicolinate] by different bipyridine-type organic spacers to form different coordination compounds with the following formulae: [Cd(µ-6apic)2]n (1), {[Cd(6apic)2(µ-bipy)]·H2O}n (2), {[Cd(6apic)2(µ-bpe)]·2H2O}n (3), [Cd(6apic)(µ-6apic)(µ-bpa)0.5]n (4) and {[Cd2(6apic)4(µ-tmbp)]·7H2O}n (5) [where bipy = 4,4´-bipyridine, bpe = 1,2-di(4-pyridyl)ethylene, bpa = 1,2-di(4-pyridyl)ethane (bpa) and tmbp = 1,3-di(4-pyridyl)propane]. Most of the synthetized compounds form infinite metal-organic rods through the linkage of the building block by the bipyridine-type linker, except in the case of compound 4 whose assembly forms a densely packed 3D architecture. All compounds were fully characterized and photoluminescent properties were studied experimentally and computationally through density functional theory (DFT) calculations. All compounds display, upon UV excitation, a similar blue emission of variable intensity depending on the linker employed for the connection of the building unit, among which compound 2 deserves to be highlighted for its room temperature phosphorescence (RTP) with an emission lifetime of 32 ms that is enlarged to 79 ms at low temperature. These good photoluminescence properties, in addition to its stability in water in a large pH range (between 2-10), motivated us to study compound 2 as a sensor for the detection of metal ions in water, showing high sensitivity for Fe3+ by means of fluorescence turn-off mechanism and unspecific turn-on response for Zn2+, respectively. Furthermore, the compound is processed as a paper-based analytical device (PAD) in which the phosphorescent emission is preserved, improving the sensing capacity toward the mentioned metal ions.
{"title":"A Family of Cd(II) Coordination Polymers Constructed from 6-aminopicolinate and Bipyridil co-Linkers: Study of their Growth in Paper and Photoluminescent Sensing of Fe3+ and Zn2+ ions","authors":"Oier Pajuelo-Corral, Inmaculada Ortiz-Gomez, Jose Angel Garcia, Antonio Rodríguez Diéguez, Iñigo J. Vitorica Yrezabal, Alfonso Salinas-Castillo, José M. Seco, Javier Cepeda","doi":"10.1039/d4dt00410h","DOIUrl":"https://doi.org/10.1039/d4dt00410h","url":null,"abstract":"In this work, we report on five novel coordination polymers (CPs) based on the linkage of the [Cd(6apic)2] building block [where 6apic = 6-aminopicolinate] by different bipyridine-type organic spacers to form different coordination compounds with the following formulae: [Cd(µ-6apic)2]n (1), {[Cd(6apic)2(µ-bipy)]·H2O}n (2), {[Cd(6apic)2(µ-bpe)]·2H2O}n (3), [Cd(6apic)(µ-6apic)(µ-bpa)0.5]n (4) and {[Cd2(6apic)4(µ-tmbp)]·7H2O}n (5) [where bipy = 4,4´-bipyridine, bpe = 1,2-di(4-pyridyl)ethylene, bpa = 1,2-di(4-pyridyl)ethane (bpa) and tmbp = 1,3-di(4-pyridyl)propane]. Most of the synthetized compounds form infinite metal-organic rods through the linkage of the building block by the bipyridine-type linker, except in the case of compound 4 whose assembly forms a densely packed 3D architecture. All compounds were fully characterized and photoluminescent properties were studied experimentally and computationally through density functional theory (DFT) calculations. All compounds display, upon UV excitation, a similar blue emission of variable intensity depending on the linker employed for the connection of the building unit, among which compound 2 deserves to be highlighted for its room temperature phosphorescence (RTP) with an emission lifetime of 32 ms that is enlarged to 79 ms at low temperature. These good photoluminescence properties, in addition to its stability in water in a large pH range (between 2-10), motivated us to study compound 2 as a sensor for the detection of metal ions in water, showing high sensitivity for Fe3+ by means of fluorescence turn-off mechanism and unspecific turn-on response for Zn2+, respectively. Furthermore, the compound is processed as a paper-based analytical device (PAD) in which the phosphorescent emission is preserved, improving the sensing capacity toward the mentioned metal ions.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141462914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guillem Aromi, Manuel Imperato, Alessio Nicolini, Jordi Ribas-Ariño, Michał Antkowiak, Olivier Roubeau, Andrea Cornia, Valentin Novikov, LEONI ALEJANDRA ALEJANDRA BARRIOS MORENO
Two new paramagnetic supramolecular helicates with formula (X@[Ni2L3])3+ (X = Cl, or Br; L = a bis-pyrazolylpyridine ligand) have been prepared and are described. Helicates of this metal are very rare with virtually no prior examples of them acting as host of anionic species. The persistence in solution of the new assemblies has been demonstrated unambiguously by mass spectrometry and paramagnetic NMR. This has allowed to establish the preference of the coordination [Ni2] host for Cl− over Br−, in agreement DFT calculations. These results show the promise of the use of metallohelicates as suitable systems for the selective encapsulation of specific anions in solution.
{"title":"Guest selectivity of [Ni2] supramolecular helicates","authors":"Guillem Aromi, Manuel Imperato, Alessio Nicolini, Jordi Ribas-Ariño, Michał Antkowiak, Olivier Roubeau, Andrea Cornia, Valentin Novikov, LEONI ALEJANDRA ALEJANDRA BARRIOS MORENO","doi":"10.1039/d4dt01611d","DOIUrl":"https://doi.org/10.1039/d4dt01611d","url":null,"abstract":"Two new paramagnetic supramolecular helicates with formula (X@[Ni2L3])3+ (X = Cl, or Br; L = a bis-pyrazolylpyridine ligand) have been prepared and are described. Helicates of this metal are very rare with virtually no prior examples of them acting as host of anionic species. The persistence in solution of the new assemblies has been demonstrated unambiguously by mass spectrometry and paramagnetic NMR. This has allowed to establish the preference of the coordination [Ni2] host for Cl− over Br−, in agreement DFT calculations. These results show the promise of the use of metallohelicates as suitable systems for the selective encapsulation of specific anions in solution.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141463104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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