Subcomponent Self-Assembly and Guest-Binding Properties of Face-Capped Fe₄L₄ ⁸⁺ Capsules

Abstract

A general method for preparing Fe(4)L(4) face-capped tetrahedral cages through subcomponent self-assembly was developed and has been demonstrated using four different C(3)-symmetric triamines, 2-formylpyridine, and iron(II). Three of the triamines were shown also to form Fe(2)L(3) helicates when the appropriate stoichiometry of subcomponents was used. Two of the cages were observed to have nearly identical Fe-Fe distances in the solid state, which enabled their ligands to be coincorporated into a collection of mixed cages. Only one of the cages combined a sufficiently large cavity with the sufficiently small pores required for guest binding, taking up a wide variety of guest species in size- and shape-selective fashion.

Anion receptor chemistry: highlights from 2008 and 2009

“…However, the authors noted that up to the addition of 1 equivalent of cyanide this system could also be used to accurately determine micromolar concentrations of CN À . 59 and a report on a series of M 4 L 6 cages of the form 96 in which the exterior framework of the cage is exchangeable. 60 In the latter, the cage is constructed by the generation of the ligands in situ as shown in Scheme 10.…”

Self-assembled metal–organic polyhedra: An overview of various applications

“…Discrete metal ion cages prepared by the reaction of metal ions and carboxylic/substituted carboxylic, Schiff-base, and pyridine ligands usually have a small activation energy barrier that can be crossed at room temperature. Pd(II)-bispyridyl cages are mostly synthesized by heating A c c e p t e d M a n u s c r i p t 6 precursor units over room temperature in a suitable solvent (DMSO-d 6 ) for 0.5 h to 24 h. Sub-component self-assembly of Fe(II) salt, aldehydes, and amines in deuterated solvents for 1 day at 50°C leads to Fe-imine complexes [56][57][58][59] . However, discrete metal-imine structures reported by Duan and co-workers are synthesized by diffusing methanol in a ligand solution with metal ions in N,N-dimethylformamide (DMF) [60,61].…”

Indistinguishability and distinguishability between amide and ester moieties in the construction and properties of M6L8 octahedral nanocages

“…leads to the formation of mixed cage [Pd 6 (L 1 ) n (L 2 ) 8−n ](NO 3 ) 12 (3, n = 0-8) comprising a statistical ligand distribution. [38][39][40] ESI-MS data of each product will be explained later in detail. These results indicate that both the donating ability and the spacer length of L 1 and L 2 are indistinguishable for the purpose of the construction of discrete coordination nanocages.…”