The coordination chemistry of -butylcalix[8]arene with transition and lanthanide metal ions.

A survey of the literature and the Cambridge Structural Database reveals thirty nine -butylcalix[8]arene-supported transition (3d, limited to V-Cu) and lanthanide metal complexes ranging in nuclearity from one to eighteen, twenty of which are homometallic and nineteen of which are heterometallic. We provide a review of the coordination chemistry of these complexes, including our own work in the area. We also provide our thoughts and perspectives on the common structural themes observed, identify gaps in knowledge and evaluate how that may inform and direct future synthetic efforts.

Stellated cuboctahedron of Fe.

The solvothermal reaction of FeCl ⋅ 4HO and HTBC[4] in a basic dmf/EtOH solution affords an [Fe ] Keplerate conforming to a stellated cuboctahedron. Magnetic and heat capacity measurements reveal spin frustration effects arising from the high symmetry. A crossover between inverse and direct magnetocaloric effects is observed at ~10 K for applied-field changes lower than 3 T.

A bis-calix[4]arene-supported [CuII16] cage.

Reaction of 2,2'-bis--Bu-calix[4]arene (HL) with Cu(NO)·3HO and -methyldiethanolamine (Me-deaH) in a basic dmf/MeOH mixture affords [CuII16(L)(Me-dea)(μ-NO)(μ-OH)(dmf)(MeOH)(HO)](HL)·16dmf·4HO (4), following slow evaporation of the mother liquor. The central core of the metallic skeleton describes a tetracapped square prism, [Cu], in which the four capping metal ions are the Cu ions housed in the calix[4]arene polyphenolic pockets. The [CuII8] square prism is held together "internally" by a combination of hydroxide and nitrate anions, with the -methyldiethanolamine co-ligands forming dimeric [CuII2] units which edge-cap above and below the upper and lower square faces of the prism.

Correction: The coordination chemistry of -butylcalix[4]arene with paramagnetic transition and lanthanide metal ions: an Edinburgh Perspective.

Correction for 'The coordination chemistry of -butylcalix[4]arene with paramagnetic transition and lanthanide metal ions: an Edinburgh Perspective' by Lucinda R. B. Wilson , , 2022, DOI: 10.

The coordination chemistry of -butylcalix[4]arene with paramagnetic transition and lanthanide metal ions: an Edinburgh Perspective.

The calix[4]arene scaffold is an extremely versatile supramolecular platform that has found widespread use across many research areas due to its synthetic versatility, controllable conformation, and the presence of cavities or clefts for tailorable guest binding. The tetraphenolic lower-rim of -butylcalix[4]arene in the cone conformation is ideal for binding a variety of paramagnetic transition and lanthanide metals, and in this Perspective we review our endeavours in using such complexes as metalloligands in the synthesis of polymetallic clusters that have fascinating structural and magnetic properties. By varying reactants, stoichiometries and reaction or crystallisation conditions it is possible to access an incredible range of clusters, all of which show consistent trends in coordination preferences and assembly behaviours.

Oxidation state variation in bis-calix[4]arene supported decametallic Mn clusters.

The reaction of MnCl·4HO, HL (2,2'-bis--Bu-calix[4]arene) and NEt in a dmf/MeOH solvent mixture results in the formation of a mixed valent decametallic cluster of formula [MnII6MnIII4(L)(μ-OH)(μ-OH)(MeOH)(dmf)(MeCN)]·MeCN (3). Complex 3 crystallises in the monoclinic space group 2/ with the asymmetric unit comprising half of the compound. Structure solution reveals that the bis-calix[4]arene ligands are arranged such that one TBC[4] moiety in each has undergone inversion in order to accommodate a [MnIII4MnII6] metallic skeleton that describes three vertex-sharing [MnIII2MnII2] butterflies.

[(VO)MII5] (M = Ni, Co) Anderson wheels.

Heterometallic Anderson wheels of formula [(VO)MII5(hmp)Cl](ClO)·2MeOH (M = Ni, 1; Co, 2) have been synthesised from the solvothermal reaction of M(ClO)·6HO and VCl with hmpH (2-(hydroxymethyl)pyridine). The metallic skeleton describes a centred hexagon, with the two vanadyl ions sitting on opposing sides of the outer ring. Magnetic susceptibility and magnetisation measurements indicate the presence of both ferromagnetic and antiferromagnetic exchange interactions.