Metal-directed supramolecular assembly of metal(II) benzoates (M=Co, Ni, Cu, Zn, Mn, and Cd) with 4,4′-bipyridine: Effects of metal coordination modes and novel catalytic activities

Song, Young Joo,Kwak, Han,Lee, Young Min,Kim, Soo Hyun,Lee, Sun Hwa,Park, Byeong Kwon,Jun, Je Yeol,Yu, Seung Man,Kim, Cheal,Kim, Sung-Jin,Kim, Youngmee Elsevier 2009 Polyhedron Vol.28 No.7

<P><B>Graphical abstract</B></P><P>We have presented a systematic investigation on the coordination polymers assembled from metal benzoates and 4,4′-bpy. Since different structures provide different coordination geometry of each metal ion, it is clear that selection of appropriate metal ions can control the coordination geometry of each metal ion to form different crystal structures. Reactivity study of seven compounds for the transesterification of a variety of esters has shown that <B>4</B>-Zn and <B>5</B>-Zn are very efficient and the best among them. It can be possible to tune the catalytic activities by changing from Zn to those metals such as Cd, a kinetically inert metal, or Cu, Mn, and Co, the redox-active metals.</P><ce:figure></ce:figure> <P><B>Abstract</B></P><P>Six polymeric metal(II)-benzoate complexes of formula [Co<SUB>2</SUB>(O<SUB>2</SUB>CPh)<SUB>4</SUB>(4,4′-bpy)<SUB>2</SUB>]<I><SUB>n</SUB></I> (<B>1</B>-Co), [Ni(O<SUB>2</SUB>CPh)<SUB>4</SUB>(H<SUB>2</SUB>O)<SUB>2</SUB>(4,4′-bpy)]<I><SUB>n</SUB></I> (<B>2</B>-Ni), [Cu<SUB>2</SUB>(O<SUB>2</SUB>CPh)<SUB>4</SUB>(4,4′-bpy)]<I><SUB>n</SUB></I> (<B>3</B>-Cu), [Zn<SUB>2</SUB>(O<SUB>2</SUB>CPh)<SUB>2</SUB>(OH)<SUB>2</SUB>(4,4′-bpy)<SUB>2</SUB>]<I><SUB>n</SUB></I> (<B>4</B>-Zn), [Zn<SUB>3</SUB>(O<SUB>2</SUB>CPh)<SUB>4</SUB>(μ-OH)<SUB>2</SUB>(4,4′-bpy)<SUB>2</SUB>]<I><SUB>n</SUB></I> (<B>5</B>-Zn), and [Cd<SUB>2</SUB>(O<SUB>2</SUB>CPh)<SUB>4</SUB>(4,4′-bpy)<SUB>2</SUB>]<I><SUB>n</SUB></I> (<B>6</B>-Cd) have been synthesized and characterized (4,4′-bpy=4,4′-bipyridine). <B>1</B>-Co and <B>6</B>-Cd show ladder-type double chains, <B>2</B>-Ni does a helical structure, <B>3</B>-Cu does a one-dimensional chain containing paddle-wheel units, <B>4</B>-Zn does a zigzag chain, and <B>5</B>-Zn does two-dimensional sheets. Since different structures provide different coordination geometry of each metal ion, it is clear that selection of appropriate metal ions can control the coordination geometry of each metal ion to form different crystal structures. Reactivity study of the compounds <B>1</B>–<B>7</B> for the transesterification of a variety of esters has shown that <B>4</B>-Zn and <B>5</B>-Zn are very efficient and the best among them. The catalyst <B>6</B>-Cd containing Cd ion, well known as an inert metal ion for the ligand substitution, also catalyzed efficiently the transesterification of a variety of esters, and its reactivity is comparable to <B>4</B>-Zn and <B>5</B>-Zn. Moreover, the redox-active metal-containing polymers, <B>1</B>-Co, <B>3</B>-Cu, and <B>7</B>-Mn, have shown efficient catalytic reactivities for the transesterification reactions, while <B>2</B>-Ni has displayed a very slow conversion. The reactivities of the compounds used in this study are in the order of <B>5</B>-Zn><B>4</B>-Zn><B>6</B>-Cd><B>7</B>-Mn∼<B>3</B>-Cu><B>1</B>-Co><B>2</B>-Ni, indicating that the non-redox metal-containing compounds (<B>5</B>-Zn, <B>4</B>-Zn, and <B>6</B>-Cd) show better activity than the redox-active metal-containing compounds (<B>7</B>-Mn, <B>3</B>-Cu, <B>1</B>-Co, and <B>2</B>-Ni). These results suggest that it is possible to tune the catalytic activities by changing from Zn to those metals such as Cd, a kinetically inert metal, or Cu, Mn, and Co, the redox-active metals.</P>

Weak Coordination Bond of Chloromethane: A Unique Way to Activate Metal Node Within an Unstable Metal–Organic Framework DUT-34

Bae Jinhee,Lee Chang Yeon,Jeong Nak Cheon 대한화학회 2021 Bulletin of the Korean Chemical Society Vol.42 No.4

Activation of metal nodes in metal–organic frameworks (MOFs) has been viewed as an essential step prior to their use for various potential applications. So far, a thermal method has been most commonly employed for the activation despite its negative influence on the structural integrity of MOFs. Meanwhile, DUT-34 has been considered as an ideal platform for the above applications due to its open-metal sites (OMSs) at the Cu node. However, the activation of DUT-34 has not been successful because of its fragile characteristics. In this article, we report the coordination-chemistry-controlled activation, namely chemical route activation, using chloromethanes. By monitoring the coordination exchangeability of chloromethanes, we demonstrate that the chloromethanes can weakly coordinate at the OMSs. Further, we demonstrate that this coordination exchange is a safe activation method to retain the framework structure of DUT-34, based on the observation that the DUT-34 placed in TCM remained intact over 2 months.

Terminology of metal-organic frameworks and coordination polymers (IUPAC Recommendations 2013)

Batten, Stuart R.,Champness, Neil R.,Chen, Xiao-Ming,Garcia-Martinez, Javier,Kitagawa, Susumu,Ö,hrströ,m, Lars,O’Keeffe, Michael,Paik Suh, Myunghyun,Reedijk, Jan De Gruyter 2013 Pure and applied chemistry. Vol.85 No.8

<P>A set of terms, definitions, and recommendations is provided for use in the classification of coordination polymers, networks, and metal–organic frameworks (MOFs). A hierarchical terminology is recommended in which the most general term is coordination polymer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains potential voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended.</P>

Rational coordination regulation in carbon-based single-metal-atom catalysts for electrocatalytic oxygen reduction reaction

Cui Xun,Gao Likun,Lu Cheng-Hsin,Ma Rui,Yang Yingkui,Lin Zhiqun 나노기술연구협의회 2022 Nano Convergence Vol.9 No.34

Single-metal-atom catalysts (SMACs) have garnered extensive attention for various electrocatalytic applications, owing to their maximum atom-utilization efficiency, tunable electronic structure, and remarkable catalytic performance. In particular, carbon-based SMACs exhibit optimal electrocatalytic activity for the oxygen reduction reaction (ORR) which is of paramount importance for several sustainable energy conversion and generation technologies, such as fuel cells and metal-air batteries. Despite continuous endeavors in developing various advanced carbon-based SMACs for electrocatalytic ORR, the rational regulation of coordination structure and thus the electronic structure of carbon-based SMACs remains challenging. In this review, we critically examine the role of coordination structure, including local coordination structure (i.e., metal atomic centers and the first coordination shell) and extended local coordination structure (i.e., the second and higher coordination shells), on the rational design of carbon-based SMACs for high-efficiency electrocatalytic ORR. Insights into the relevance between coordination structures and their intrinsic ORR activities are emphatically exemplified and discussed. Finally, we also propose the major challenges and future perspectives in the rational design of advanced carbon-based SMACs for electrocatalytic ORR. This review aims to emphasize the significance of coordination structure and deepen the insightful understanding of structure-performance relationships.

Construction of crystal structures of metal(II)–benzoates (M=Mn, Ni, Co, Cu, Zn, and Cd) and 1,2-bis(4-pyridyl)ethane: Effects of metal coordination modes and their catalytic activities

Kim, Soo Hyun,Park, Byeong Kwon,Song, Young Joo,Yu, Seung Man,Koo, Hyo Geun,Kim, Eun Young,Poong, Jung In,Lee, Ju Hoon,Kim, Cheal,Kim, Sung-Jin,Kim, Youngmee Elsevier 2009 Inorganica chimica acta Vol.362 No.11

<P><B>Graphical abstract</B></P><P>The coordination polymers assembled from metal–benzoates and 1,2-bis(4-pyridyl)ethane (bpa) showed two kinds of structures: parallelogram-like two-dimensional sheets for Co, Ni, and Cd, and one-dimensional chains for Mn, Cu, and Zn. The compounds <B>1</B>–<B>6</B> catalyzed the transesterification of a variety of esters.</P><ce:figure></ce:figure> <P><B>Abstract</B></P><P>Five polymeric metal(II)–benzoate complexes of formula [Mn(O<SUB>2</SUB>CPh)<SUB>2</SUB>(CH<SUB>3</SUB>OH)<SUB>2</SUB>(bpa)]<SUB>n</SUB> (<B>1</B>-Mn), [Co(O<SUB>2</SUB>CPh)<SUB>2</SUB>(H<SUB>2</SUB>O)(bpa)<SUB>1.5</SUB>]<I><SUB>n</SUB></I> (<B>2</B>-Co), [Ni(O<SUB>2</SUB>CPh)<SUB>2</SUB>(H<SUB>2</SUB>O)(bpa)<SUB>1.5</SUB>]<I><SUB>n</SUB></I> (<B>3</B>-Ni), [Cu(O<SUB>2</SUB>CPh)<SUB>2</SUB>(CH<SUB>3</SUB>OH)<SUB>2</SUB>(bpa)]<I><SUB>n</SUB></I> (<B>4</B>-Cu), and [Cd(O<SUB>2</SUB>CPh)<SUB>2</SUB>(bpa)<SUB>1.5</SUB>]<I><SUB>n</SUB></I> (<B>6</B>-Cd) have been synthesized and characterized (bpa=1,2-bis(4-pyridyl)ethane). They showed two kinds of structures: parallelogram-like two-dimensional sheets for Co, Ni, and Cd, and one-dimensional chains for Mn, Cu, and Zn. Since similar structures provide similar coordination geometries, the structures depend on the coordination geometries of metal ions. The compounds <B>1</B>-Mn, <B>2</B>-Co, <B>4</B>-Cu, <B>5</B>-Zn, and <B>6</B>-Cd have catalyzed efficiently the transesterification of a variety of esters, while <B>3</B>-Ni has displayed a very slow conversion. The reactivity of catalyst <B>6</B>-Cd containing Cd ion, well known as an inert metal ion for the ligand substitution, was found to be comparable to that of <B>5</B>-Zn. The reactivities of the compounds used in this study are in the order of <B>5</B>-Zn><B>6</B>-Cd><B>1</B>-Mn><B>4</B>-Cu><B>2</B>-Co≫<B>3</B>-Ni, indicating that the non-redox metal-containing compounds (<B>5</B>-Zn and <B>6</B>-Cd) show better activity than the redox-active metal-containing compounds (<B>1</B>-Mn, <B>4</B>-Cu, <B>2</B>-Co, and <B>3</B>-Ni).</P>

Metal-polyphenol Complexes as Versatile Building Blocks for Functional Biomaterials

김정아,이기문,남윤성 한국생물공학회 2021 Biotechnology and Bioprocess Engineering Vol.26 No.5

Natural metal-organic complexes have gained much attention due to their self-assembly behaviors and photochemical properties. They perform various biological processes, including catalysis, anti-oxidation, molecular transport, and structural organization. Recently, the bioinspired metal-phenolic complexes have been widely adopted as molecular scaffolds and redox-active molecules for the fabrication of functional materials. This review focuses on recent studies on the applications of metalpolyphenol complexes as bioinspired materials to build functional biomaterials possessing unique physical and chemical properties. Metal-phenolic coordination provides a simple fabrication route to complex and hierarchical structures as found in metal-ligand complexes in nature, leading to assembled supramolecular materials and robust interfaces of metal species with polyphenols. Furthermore, the metal-polyphenol chemistry features the versatile biochemical and structural functions of metal species through complexation with polyphenols as biocompatible ligands. This article is concluded with a discussion on the redox properties of metal-phenolic coordination potentially useful for biomedical applications.

Anion-dependent soft metal complexes with an O₂S₃-macrocycle: From monomer and dimer to polymer with <i>endo</i>-, <i>exo</i>-, and endo/exocyclic coordination modes

Kim, Yoonji,Ju, Huiyeong,Jung, Jong Hwa,Lee, Jai Young,Lee, Shim Sung Elsevier 2019 Inorganic chemistry communications Vol.100 No.-

<P><B>Abstract</B></P> <P>Five soft metal complexes (<B>1</B>–<B>5</B>) of a 16-membered O<SUB>2</SUB>S<SUB>3</SUB>-macrocycle (<B>L</B>) with different topologies and coordination modes, including discrete to infinite forms, and <I>endo</I>-, <I>exo</I>-, and endo/exo-coordination, were prepared and structurally characterized. Both mercury(II) complexes, [Hg(<B>L</B>)(NO<SUB>3</SUB>)<SUB>2</SUB>] (<B>1</B>) and [Hg(<B>L</B>)(DMF)<SUB>2</SUB>](ClO<SUB>4</SUB>)<SUB>2</SUB>·DMF (<B>2</B>), with nitrate and perchlorate anions, respectively, show a typical endocyclic structure. Two nitrate ions in <B>1</B> occupy the coordination sites, while two DMF molecules participate to the coordination sphere in <B>2</B> remaining two perchlorate ions uncoordinated. It is found that the anion-exchange of <B>2</B> in the solid state induced the conversion to <B>1</B> which involves the rearrangement of the coordination sphere. In silver(I) complexations, nitrate afforded a cyclic dimer complex [Ag<SUB>2</SUB>(<B>L</B>)<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>2</SUB>] (<B>3</B>). While hexafluorophosphate gave a 1-D zigzag coordination polymer {[Ag(<B>L</B>)]PF<SUB>6</SUB>}<SUB> <I>n</I> </SUB> (<B>4</B>). Interestingly, triflate led to the isolation of a tetranuclear bis(macrocycle) complex, {[<SUP> <I>endo</I> </SUP>Ag(<B>L</B>)(CF<SUB>3</SUB>SO<SUB>3</SUB>)]<SUB>2</SUB>[<I>μ</I>-<SUP> <I>exo</I> </SUP>Ag<SUB>2</SUB>(CF<SUB>3</SUB>SO<SUB>3</SUB>)<SUB>2</SUB>]} (<B>5</B>), which are dominated by the coordination modes (<SUP> <I>endo</I> </SUP>Ag and <SUP> <I>exo</I> </SUP>Ag) of <B>L</B> toward two types of silver(I) centers. For instance, two endocyclic complex units, <SUP> <I>endo</I> </SUP>Ag<SUB>2</SUB>(<B>L</B>)<SUB>2</SUB>(CF<SUB>3</SUB>SO<SUB>3</SUB>)<SUB>2</SUB>, are linked by exocyclic metallacycle, [<I>μ</I>-<SUP> <I>exo</I> </SUP>Ag<SUB>2</SUB>(CF<SUB>3</SUB>SO<SUB>3</SUB>)<SUB>2</SUB>], to give a 4:2 (metal-to-ligand) stoichiometry. From the results, it is obviously clear that the role of anions mostly is responsible to such structural diversity based on the <I>exo</I>-coordination mode.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Silver(I) and mercury(II) complexes of O<SUB>2</SUB>S<SUB>3</SUB>-macrocycle were prepared. </LI> <LI> Mercury(II) perchlorate complex was converted to nitrate form via anion-exchange. </LI> <LI> A tetranuclear bis(macrocycle) silver(I) triflate complex was isolated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Kinetically controlled chiral metal‐coordinated supramolecular polymerization accompanying helical inversion or morphological transformation

임설아,정성호,정종화 대한화학회 2023 Bulletin of the Korean Chemical Society Vol.44 No.4

Here, we describe the recent progress on metal-coordinated supramolecular structures with unique characteristics and controlled helicity based on coordi- nation geometry and dynamic intermolecular binding events. The current major research area is the self-assembly of a metal-containing molecule into nanomaterials. It generated a large number of supramolecular polymers, which have various structures and functions. Although the dynamic coordination complexation reactions between various metal ions and ligands are spontane- ous, we successfully achieved unique morphological transformations with heli- cal inversion of metal-containing supramolecular polymers via the kinetic control of dynamic coordination complexation reactions. Our findings have a significant impact on the development of novel and advanced supramolecular materials, and dynamic coordination bonds in the molecular design of metal- containing complexes for modulating self-assembly pathways, which may be relevant for the fabrication of supramolecular materials with interesting proper- ties. Our contributions may be useful to the understanding of chiral assembly processes in biological systems.

Coordination Control of Multiple Electrical Excited Synchronous Motors and Its Application in High-Power Metal-Rolling Systems

Jing Shang,Xiaohong Nian,Yong Liu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

This study focuses on the coordination control problem of multiple electrical excited synchronous motor systems. A robust coordination controller is designed on the basis of cross coupling and an interval matrix. The proposed control strategy can deal with load uncertainty. In addition, the proposed control strategy is applied to a high-power metal-rolling system. Simulation and experiment results demonstrate that the proposed control strategy achieves good dynamic and static performance. It also shows better coordination performance than traditional proportional–integral controllers.

Coordination Control of Multiple Electrical Excited Synchronous Motors and Its Application in High-Power Metal-Rolling Systems

Shang, Jing,Nian, Xiaohong,Liu, Yong The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

This study focuses on the coordination control problem of multiple electrical excited synchronous motor systems. A robust coordination controller is designed on the basis of cross coupling and an interval matrix. The proposed control strategy can deal with load uncertainty. In addition, the proposed control strategy is applied to a high-power metal-rolling system. Simulation and experiment results demonstrate that the proposed control strategy achieves good dynamic and static performance. It also shows better coordination performance than traditional proportional-integral controllers.