Chiral Metallacrown Supramolecular Compartments that Template Nanochannels: Self‐Assembly and Guest Absorption

Abstract

Blue plates of 1 were grown from a water solution at 25 deg. C. A crystal of dimensions 0.34 x 0.20 x 0.11 mm was mounted on a Bruker SMART APEX CCD-based X-ray diffractometer equipped with a low temperature device and fine focus Mo-target X-ray tube (λ = 0.71073 A) operated at 1500 W power (50 kV, 30 mA). The X-ray intensities were measured at 85(1) K; the detector was placed at a distance 5.055 cm from the crystal. A total of 5190 frames were collected with a scan width of 0.5° in ω and 0.45° in phi with an exposure time of 20 s/frame. The integration of the data yielded a total of 117140 reflections to a maximum 2θ value of 56.72° of which 37759 were independent and 34737 were greater than 2σ(I). The final cell constants (Table 1) were based on the xyz centroids of 9001 reflections above 10σ(I). Analysis of the data showed negligible decay during data collection; the data were processed with SADABS and corrected for absorption. The structure was solved and refined with the Bruker SHELXTL (version 2008/3) software package, using the space group P1 with Z = 1 for the formula C 111 H 178 N 20 O 56 Cu 10 Dy 2. All non-hydrogen atoms were refined anisotropically with the hydrogen atoms placed in idealized positions. Full matrix least-squares refinement based on F 2 converged at R1 = 0.0448 and wR2 = 0.1260 [based on I > 2sigma(I)], R1 = 0.0508 and wR2 = 0.1337 for all data. Additional details are presented in Table S1 and are given as Supporting Information in a CIF file.

The crystal structures of {LnCu5}3+ (Ln = Gd, Dy and Ho) 15-metallacrown-5 complexes and a reevaluation of the isotypic EuIII analogue

“…In addition, a number of heteropolynuclear metallacrown complexes have been shown to possess single molecule magnetic (SMM) behaviour (Ostrowska et al, 2016;Wang et al, 2019), bright luminescence with high quantum yields (Nguyen et al, 2018;Martinić et al, 2017) and the ability to serve as building blocks for the generation of supramolecular assemblies and coordination polymers (Pavlishchuk et al, 2014(Pavlishchuk et al, , 2017b. The utilization of heteronuclear cationic 15-metallacrown-5 complexes as initial building blocks has also led to porous structures that are able to absorb various guest molecules (Lim et al, 2010). The selection of the initial building blocks with labile counteranions (e.g.…”

Assembly of Near‐Infrared Luminescent Lanthanide Host(Host–Guest) Complexes With a Metallacrown Sandwich Motif

“…Ln III MCs [11] have been prepared that display single-molecule magnetism [12] and selectively encapsulate anions in monomeric cavitands or dimeric compartments. [13] Chiral Ln III [15-MC-5] complexes can serve as building blocks for mesoporous solids, [14] resolved helices, [15] and noncentrosymmetric solids that display second-harmonic generation. [16] To date, Ln III MCs have been prepared only with ring metals that contain partially filled d orbitals, which could provide a quenching pathway for luminescence.…”

Design of 2D Porous Coordination Polymers Based on Metallacrown Units

“…MCs are solution stable under a wide range of conditions and can be easily isolated in the solid state. Nevertheless, only a few examples of extended frameworks or supramolecular architectures composed of MC units have been reported to date. Furthermore, none of these compounds display the permanent porosity that is typical of porous coordination polymers.…”

“…However, permanent porosity was not observed for either one of the lattices . Furthermore, there are a few examples of void‐space containing networks formed by the aggregation of MCs held together by weak interactions . As with the first example, the interactions established in these architectures do not provide sufficient structural stabilization for the lattices to exhibit significant gas uptake properties.…”

“…A detailed description of the coordination polymers based on metallacrowns has been reported recently . Compared to the compounds known to date, network 1 , with its average calculated pore diameter of 1.2 nm and 36 % of total void volume, possesses the second widest pores of all MC‐based systems, behind the mesoporous aggregate La III /Cu II 15‐MC‐5 (average pore diameter of 2.4 nm with 43 % of unit cell voids) . However, the aforementioned mesoporous material does not withstand solvent evacuation and, therefore, does not show permanent porosity due to structural collapse upon solvent removal.…”