A fluorescent calixarene-based dimeric capsule constructed a M-terpyridine interaction: cage structure, inclusion properties and drug release.

Two analogues of capsule-like fluorescent cages have been constructed by dimerization of terpyridine-containing calixarene derivatives utilizing a M-terpyridine (M = Zn and Cd) interaction. H NMR spectral studies show that the self-assembled molecular capsules ZnL1 and CdL1 have a highly symmetrical -structure. The encapsulation of the anticancer drug mercaptopurine in their cavities has been documented by NMR, ESI-TOF-MS, fluorescence switching, and molecular simulation, indicating that strong S-π and π-π interactions between drug and cage are of importance for the host-guest binding.

Catalytic Space Engineering of Porphyrin Metal-Organic Frameworks for Combined CO Capture and Conversion at a Low Concentration.

Porous porphyrin metal-organic frameworks (PMOFs) provide promising platforms for studying CO capture and conversion (C3) owing to their versatility in photoelectric, catalytic, and redox activities and porphyrin coordination chemistry. Herein, we report the C3 application of two PMOFs by engineering the coordination space through the introduction of two catalytic metalloporphyrins doped with rhodium or iridium, Rh-PMOF-1 and Ir-PMOF-1, both of which can serve as heterogeneous catalysts for the chemical fixation of CO into cyclic carbonates with yields of up to 99 %. Remarkably, the catalytic reactions can effectively proceed under low CO concentrations and high yields of 83 % and 73 % can be obtained under 5 % CO in the presence of Rh-PMOF-1 and Ir-PMOF-1, respectively.

Regio- and Enantioselective Photodimerization within the Confined Space of a Homochiral Ruthenium/Palladium Heterometallic Coordination Cage.

The photoinduced regio- and enantioselective coupling of naphthols and derivatives thereof is achieved in the confined chiral coordination space of a Ru metalloligand based cage. The racemic or enantiopure cages encapsulate naphthol guests, which then undergo a regiospecific 1,4-coupling, rather than the normal 1,1-coupling, to form 4-(2-hydroxy-1-naphthyl)-1,2-napthoquinones; moderate stereochemical control is achieved with homochiral cages. The photoreactions proceed under both aerobic and anaerobic conditions but through distinct pathways that nevertheless involve the same radical intermediates.

Chelant extraction of heavy metals from contaminated soils using new selective EDTA derivatives.

Soil washing is one of the few permanent treatment alternatives for removing metal contaminants. Ethylenediaminetetraacetic acid (EDTA) and its salts can substantially increase heavy metal removal from contaminated soils and have been extensively studied for soil washing. However, EDTA has a poor utilization ratio due to its low selectivity resulting from the competition between soil major cations and trace metal ions for chelation.

Inherently chiral calixarenes: synthesis, optical resolution, chiral recognition and asymmetric catalysis.

Inherently chiral calixarenes, whose chirality is based on the absence of a planar symmetry or an inversion center in the molecules as a whole through the asymmetric array of several achiral groups upon the three-dimensional calix-skeletons, are challenging and attractive chiral molecules, because of their potential in supramolecular chemistry. The synthesis and optical resolution of all varieties of inherently chiral calixarenes are systematically discussed and classified, and their applications in chiral recognition and asymmetric catalysis are thoroughly illustrated in this review.