Size-Induced Highly Selective Synthesis of Organometallic Rectangular Macrocycles and Heterometallic Cage Based on Half-Sandwich Rhodium Building Block

Abstract

The controlled synthesis of organometallic supramolecular macrocycles cages remains interesting and challenging work in the field of supramolecular chemistry. Here, two tetranuclear rectangular macrocycles and an octuclear cage were designed and synthesized utilizing a rigid and functionalized pillar linker, 2,6-bis(pyridin-4-yl)-1,7-dihydrobenzo [1,2-d:4,5-d′]diimidazole (BBI4PY) based on three half-sandwich rhodium building blocks bearing different sizes. X-ray crystallography in combination with 1H NMR spectroscopy elucidated that the two building blocks with shorter spacers only result in rectangular macrocycles. However, the building block of bulkier size to avoid the π-π stacking interactions between two ligands BBI4PY led to the formation of an octuclear cage complex. The latter cage contains two types of metal ions, namely Rh3+ and Cu2+, showing significant characteristics of heterogeneous metal-assembling compounds. In addition, the cage accommodates two free isopropyl ether solvent molecules, thus displaying host–guest behavior.

Heterometallic cages: synthesis and applications

“…10) to the construction of heterometallic three dimensional architectures has been widely used in recent years. 107,163,165–167 Unlike the symmetry interaction approach, the directional bonding method utilises capped metal ions, whereby the kinetically inert capping ligands direct the approach of the remaining bridging ligands or metallo–ligands to predictably form the resulting architecture. Commonly shaped structures include prisms, 165–167 and lanterns.…”

“…107,163,165–167 Unlike the symmetry interaction approach, the directional bonding method utilises capped metal ions, whereby the kinetically inert capping ligands direct the approach of the remaining bridging ligands or metallo–ligands to predictably form the resulting architecture. Commonly shaped structures include prisms, 165–167 and lanterns. 107,114,163,168 A wide range of functional heterometallic cages have been generated by exploiting the directional bonding approach and combining it with the heterometallic methods outlined in Fig.…”

“…Similar to the above example, the Ma group have also recently used a heterometallic ligand to synthesise a prismatic rhodium/copper heterometallic cage (Scheme 20). 167 In this work, heterometallic ligand L23 a and organic ligand L23 b were combined in a one pot synthesis to afford C23 . Two of the heterometallic ligands coordinated with the organic ligands via a rhodium-pyridyl bond forming a macrocyclic shape.…”

Fast and Reversible Luminescence “Turn-On” Detection of Ethanol Vapor by H-Bonded Molecular Crystal Thin Film

“…In particular, the good fluorescence of the BBI4PY molecule provides a great opportunity for various types of fluorescence detection. On the basis of this chromophore, Mandal synthesized a stable Zn-MOF, presenting the selective sensing of Fe 3+ and 2,4,6-trinitrophenol (TNP) in water with detection limits of 3.7 and 1.8 ppm, respectively. − In this work, a novel hydrogen-bonded organic framework, LYNU-10 , was synthesized successfully, through N–H···N hydrogen-bonding and π···π stacking interactions of the BBI4PY chromophore. It shows broad fluorescence emission ranging from blue to orange by detection of different concentrations of H-bonded molecular crystal nanoparticles in an ethanol solvent.…”

The Selective CO2 Adsorption and Photothermal Conversion Study of an Azo-Based Cobalt-MOF Material

“…To date, numerous MOFs have been designed for the adsorption and separation of CO 2 [ 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. Luo et al made many outstanding efforts in the field of gas adsorption [ 44 , 45 , 46 , 47 , 48 , 49 ].…”