Lanthanide Supermolecular Transformers Induced by K⁺ and CO₂

Abstract

The transfer of configuration information from supramolecular helices is a ubiquitous phenomenon in nature. DNA and proteins often change their helical structure in response to particular external stimuli and can activate important related events through sophisticated mechanisms. Attempts to create artificial multiple-stranded helicates that can adjust the configuration under external stimuli have also met with limited success. Using a simple ligand, we now show multiple-stranded lanthanide helicates that transform efficiently. Lanthanide and ligand are successfully self-assembled into different multiple helical supermolecular clusters using different templates. Additionally, these intelligent supermolecular transformers can also be transformed by different external stimuli and realize the selective recognition and fixation of the corresponding ions and molecules.

Adaptive coordination assemblies based on a flexible tetraazacyclododecane ligand for promoting carbon dioxide fixation

“…4B(e) and (f)). Although many coordination hosts that can fix CO 2 by binding with carbonate have been reported, 95–102 the newly formed strong metal–oxygen interactions make these hosts unable to be reused. Thus, tube 1-Zn represents a rare coordination host that can catalyze CO 2 conversion like carbonic anhydrase.…”

“…Further experiments showed that after removal of CO 3 2encapsulated by cavity, the tube 1-Zn can be regenerated and reused (Figure 4B e-f). Although many coordination hosts that can fix CO 2 by binding with carbonate have been reported, [95][96][97][98][99][100][101][102] the new-formed strong metal-oxygen interactions make these hosts cannot be reused. Thus, tube 1-Zn represents a rare coordination host that can catalyze CO 2 conversion like carbonic anhydrase.…”

“…9–13 Coordination-directed self-assembly has been proven to be an effective approach toward the predictable construction of multicomponent artificial hosts, 14–77 where enhanced guest reactivity, 73,74,78–87 stabilization of metastable species, 88–90 and unusual reaction pathways 78,91–94 have been realized. While atmospheric CO 2 sequestration by selective binding of carbonate with coordination hosts has already been reported, 95–102 adaptive coordination hosts that contain multiple active metal sites and can reversibly encapsulate and release the carbonate are still rare.…”

A Discrete 3d–4f Metallacage as an Efficient Catalytic Nanoreactor for a Three-Component Aza-Darzens Reaction

“…We have been interested in the construction of novel high-nuclearity clusters and the determination of the structure–activity relationship of these lanthanide complexes. ,, To controllably prepare a supramolecular nanocage based on heterometallic complex and exploit the application of the coordination cage in catalysis, an unusual and discrete 3d–4f metallacage, [Zn 2 Er 4 (H 2 L ) 4 (NO 3 )­Cl 2 (H 2 O)]·NO 3 · x CH 3 OH· y H 2 O ( Zn 2 Er 4 ), was synthesized by the introduction of a semirigid and nonsymmetric bridging ligand (H 5 L ) with rich metal-chelating sites, which could effectively fix more lanthanide ions and coordinate with transition-metal ions via the self-adjustment of different coordination atoms. The 3d–4f Zn 2 Er 4 cage possesses a quadruple-stranded structure, and all ligands wrap around open spherical space within the core (Scheme ).…”

Exploring the Biological Properties of Zn(II) Bisthiosemicarbazone Helicates

“…Between them, helicates can be considered very promising candidates that can be precisely designed to exhibit inherent bioactivity. The term "helicate" is referred to a particular class of self-assembled metallosupramolecular compounds, in which conveniently designed ligands wrap around two or more metal ions and form a double stranded helix [21][22][23][24][25].…”