Nuclearity control in calix[4]arene-based zinc(ii) coordination complexes

Abstract

Three zinc based coordination complexes were selectively generated in the crystalline phase using new flexible molecular “tweezers” calix[4]arene derivative ligand decorated with two appended carboxylic moieties and benzyl spacers ((3-4H))....

Porous nickel and cobalt hexanuclear ring-like clusters built from two different kind of calixarene ligands – new molecular traps for small volatile molecules

“…One of the Co 2+ cations is also bearing a free water molecule. Metallic triangles are formed within the [3(M3DMF(OH2)2)] 2+ entities, involving two short (3.0102(36) and 3.0233(21)Å) and one long (3.8144(30)Å) Co-Co distances (see Table2), a µ3-coordinated water molecule, as already observed for trinuclear based compounds,52,53 is present in the middle of the non-isosceles triangle, with Co-O distances in the 2.044(3)-2.100(3) Å range.…”

“…52 This was also recently confirmed using another pincer like analogue, presenting benzoate ligand leading also to a trinuclear Zn(II) coordination compound. 53 In this work, using a calixarene based ligand ((2-4H), figure 1) presenting a shorter spacer than (4-4H), two isomorphous polynuclear complexes have been obtained. But in contrast to what have been already observed using this approach, hexanuclear ring-like coordination species have been obtained and structurally characterized using X-ray diffraction on single crystals.…”

“…In this compound, both (2-2H) 2and 3 4are cone shaped which is in accordance with the previously reported data for their related coordination compounds. 52,53 Neutral hexanuclear ring-shaped clusters result from the bridging of trinuclear [3(M3DMF(OH2)2)] 2+ entities by (2-2H) 2units and present inversion symmetry centre located between the trimetallic nodes, leading to the formation of internal spherical cavity with a diameter of ca 8.2Å, an external diameter of ca 26Å. The obtained compound displays a disc shape as shown in figure 2 a-b, with a thickness of ca 10Å, and finally a ring like shape with a pore of 8.2Å, in the middle of the disc.…”

A versatile enrichment of functionalized calixarene as a facile sensor for amino acids

“…As a result, the L-isomers of the amino acid ester hydrochlorides formed better chiral selector complexes than did the D-isomers. [88] Recently, Yang and colleagues created an electrochemical chiral interface based on chiral calix [4] arene and cetyltrimethylammonium bromide self-assembly (23) to detect tryptophan isomers. The CCA-CTAB self-assembly was aided by the lone pair of oxygen atoms in calixarene and the positive charge of the ammonium group in CTAB.…”

“…From the time of this discovery these have expanded from their origins to cover synthetic organic chemistry (receptor design), [22] coordination chemistry (metal-ligand complexes), [23] physical chemistry (experimental and computational calculations), [24] and biochemistry (substrate binding and recognition), [25] and this field has seen exceptional development. In last decade, interest in the field of supramolecular chemistry has increased dramatically.…”