Four porphyrins equipped with imidazolium rings on the positions of their aryl groups were prepared and used as tetrakis(-heterocyclic carbene) (NHC) precursors for the synthesis of porphyrin cages assembled from eight NHC-M bonds (M = Ag or Au). The conformation of the obtained porphyrin cages in solution and their encapsulation properties strongly depend on the structure of the spacer -(CH)- ( = 0 or 1) between aryl groups and peripheral NHC ligands. In the absence of methylene groups ( = 0), porphyrin cages are rather rigid and the short porphyrin-porphyrin distance prevents the encapsulation of guest molecules like 1,4-diazabicyclo[2.2.2]octane (DABCO). By contrast, the presence of methylene functions ( = 1) between aryl groups and peripheral NHCs offers additional flexibility to the system, allowing the inner space between the two porphyrins to expand enough to encapsulate guest molecules like water molecules or DABCO. The peripheral NHC-wingtip groups also play a significant role in the encapsulation properties of the porphyrin cages.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.1c02868DOI Listing

Publication Analysis

Top Keywords

porphyrin cages
20
encapsulation properties
12
aryl groups
12
cages assembled
8
groups peripheral
8
guest molecules
8
porphyrin
5
cages
5
groups
5
synthesis characterization
4

Similar Publications

A Zn-coordinated porphyrinic artificial solid-electrolyte interphase (αSEI) layer, named [Zn]PP-4COO-(Zn), was developed to improve the reversibility of zinc metal plating/stripping in aqueous zinc-ion batteries (ZIBs). Inspired by nitrogen-terminating sites of biological molecules coordinating and transporting zinc in zinc metabolic processes, the αSEI layer was designed with zinc ions connecting porphyrinic building blocks to form two-dimensional clathrate sheets and stacking -plane sheets along the -axis to allow N cages to align and form porphyrinic N channels for zinc transport. The [Zn]PP-4COO-(Zn) αSEI layer was Zn-conductive and structurally durable during repeated stripping/plating.

View Article and Find Full Text PDF

The controllable encapsulation of host molecules (such as porphyrin, phthalocyanine, crown ether, calixarene or cucurbituril organic macrocycles, cages, metal-organic polyhedrons and enzymes) into the pores of metal-organic frameworks (MOFs) to form host-in-host (host@MOF) materials has attracted increasing research interest in various fields. These host@MOF materials combine the merits of MOFs as a host matrix and functional host molecules to exhibit synergistic functionalities for the formation of guest@host@MOF materials in sorption and separation, ion capture, catalysis, proton/ion conduction and biosensors. (This guest@host@MOF construction is reminiscent of Russian (Matrjoschka) dolls which are nested dolls of decreasing size placed one inside another.

View Article and Find Full Text PDF

Energy flow in biomolecules is a dynamic process vital for understanding health, disease, and applications in biotechnology and medicine. In crowded environments, where biomolecular functions are modulated, comprehending energy flow becomes crucial for accurately understanding cellular processes like signaling and subsequent functions. This study employs ultrafast transient absorption spectroscopy to demonstrate energy funneling from the photoexcited heme of bovine heart cytochrome to the protein exterior, in the presence of common synthetic (Dextran 40, Ficoll 70, PEG 8 and Dextran 70) and protein-based (BSA and β-LG) crowders.

View Article and Find Full Text PDF

Herein, we report enhancement in chemical stability of the imine-based porphyrinic cage PL by converting it into a robust carbamate porphyrinic cage, c-PL, through a two-step post-synthetic modification process. First, the imine bonds in PL were reduced to form an amine-based cage, r-PL, followed by carbamation using N,N'-carbonyldiimidazole (CDI) to yield c-PL. The resulting carbamate cage exhibits high stability under acidic and basic conditions (pH 1-13) and in the presence of moisture.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on creating porphyrin-based nanohoops, rings, and cages, which are difficult to synthesize but have desirable properties.
  • The authors describe a template-free method to synthesize a unique bithiophene-bridged porphyrin cyclophane, revealing its strained structure and electronic characteristics through X-ray analysis.
  • The resulting compounds exhibit interesting aromatic properties and reactivity, with the dication being globally aromatic and able to relieve strain through nucleophilic addition with chloride.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!