Gold-Based Coronands as Hosts for M3+ Metal Ions: Ring Size Matters
Suelen Ferreira Sucena1, Türkan Ilgin Demirer1, Anna Baitullina1
1Institute of Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstr. 34/36, 14195 Berlin, Germany.
Molecules (Basel, Switzerland)
|July 29, 2023
Summary
This study demonstrates a novel self-assembly method for multinuclear coordination compounds using metal ion acidity and geometry. Gold-based coronands encapsulate various metal ions, forming structures whose size depends on the central ion
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Controlled synthesis of multinuclear coordination compounds is crucial.
- Ligand properties and metal ion characteristics influence aggregate formation.
- Pearson's acid-base theory and coordination preferences offer organizational principles.
Purpose of the Study:
- To explore the self-assembly of gold-based multinuclear coordination compounds.
- To investigate the templating effect of central metal ions (M3+) on coronand formation.
- To understand the relationship between central ion size and the resulting assembly structure.
Main Methods:
- One-pot reactions utilizing 2,6-dipicolinoylbis(N,N-diethylthiourea) (H2L1ethyl) ligand.
- Inclusion of gold(I) precursors ([AuCl(tht)]) and various M3+ salts (Sc, Y, La, Ln, Ga, In).
- Structural characterization of the resulting gold-based coronands hosting central metal ions.
Main Results:
- Formation of gold-based {Au3(L1ethyl)3}3+ or {Au2(L1ethyl)2}2+ coronands.
- Central M3+ ions template the formation of these coronands.
- Coronand ring size is dependent on the ionic radii of the encapsulated M3+ ions.
- Small ions like Ga3+ form [Ga{Au2(L1ethyl)2}]+ assemblies.
- Larger ions (Sc3+, In3+) yield neutral [M{Au3(L1ethyl)3}] units with nine-coordinate central ions.
Conclusions:
- Demonstrates a versatile method for constructing metal-templated multinuclear coordination compounds.
- Highlights the role of metal ion properties (acidity, size) in directing self-assembly.
- Presents novel gold-based coronands with tunable structures based on encapsulated guest ions.
More Related Videos
13:21Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
15.0K
10:31Detection and Recovery of Palladium, Gold and Cobalt Metals from the Urban Mine Using Novel Sensors/Adsorbents Designated with Nanoscale Wagon-wheel-shaped Pores
Published on: December 6, 2015
28.1K
Related Concept Videos
03:45Formation of Complex Ions
23.7K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
23.7K
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
405
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
405
01:19Complexation Equilibria: The Chelate Effect
555
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
555
02:51Metal-Ligand Bonds
21.0K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
21.0K
02:57Coordination Number and Geometry
16.1K
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
16.1K
00:56Extraction: Advanced Methods
487
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
487