The “CHON” compatible water-soluble ligand 3,3′-(pyridine-2,6-diylbis(1H-1,2,3-triazole-4,1-diyl))bis(propan-1-ol) (PTD) has shown promise for selectively stripping actinide ions from an organic phase containing both actinide and lanthanide ions, by preferential complexation of the former. Aiming at improving its complexation properties, PTD-OMe was synthesized, bearing a methoxy group on the central pyridine ring, thus increasing its basicity and hence complexation strength. Unfortunately, solvent extraction experiments in the range of 0.1–1 mol/L nitric acid proved PTD-OMe to be less efficient than PTD. This behavior is explained by its greater pKa value (pKa = 2.54) compared to PTD (pKa = 2.1). This counteracts its improved complexation properties for Cm(III) (log β3(PTD-OMe) = 10.8 ± 0.4 versus log β3(PTD) = 9.9 ± 0.5).

Starting from the promising Minor Actinides (MA) affinity showed by the water-soluble ligands (PyTri-polyols) with the 2,6-bis[1H-1,2,3-triazol-4-yl]-pyridine chelating unit, different attempts were made to functionalize the same N 3-donor set with alkyl chains in the 1-position of triazole nuclei to obtain novel lipophilic extractants endowed with comparable MA selectivity. Solubility in organic diluents was found to be the main limitation to the development of efficient lipophilic ligands, thus resulting in less efficient extractants with respect to their hydrophilic analogues and sometimes impairing the selectivity evaluation. Interestingly, the ethyl hexyl derivative (PTEH) showed adequate extraction capability and a MA selectivity comparable to that of the hydrophilic PyTri family.

Single-component conductors based on neutral organic radicals have received a lot of attention due to the possibility that the unpaired electron can serve as a charge carrier without the need of a previous doping process. Although most of these systems are based on delocalized planar radicals, we present here a nonplanar and spin localized radical based on a tetrathiafulvalene (TTF) moiety, linked to a perchlorotriphenylmethyl (PTM) radical by a conjugated bridge, which exhibits a semiconducting behavior upon application of high pressure. The synthesis, electronic properties, and crystal structure of this neutral radical TTF-Ph-PTM derivative (1) are reported and implications of its crystalline structure on its electrical properties are discussed. On the other hand, the non-radical derivative (2), which is isostructural with the radical 1, shows an insulating behavior at all measured pressures. The different electronic structures of these two isostructural systems have a direct influence on the conducting properties, as demonstrated by band structure DFT calculations.

The iodoalkynyl group is a ditopic synthon, able to act as a halogen bond (XB) donor through the iodine atom and as an XB acceptor on the CC triple bond. With the aim of exploring the selfassembly properties via XB of calix[4]arene macrocycles containing this synthon, we synthesized and characterized a tetra(iodopropargyl)calix[4]arene (3). In the solid state, all the iodoalkynyl units of 3 are involved in intermolecular XB interactions as both donors and acceptors, resulting in a two-dimensional network of calixarene double layers. On the contrary, in the cocrystal of 3 with 4,4′-bipyridine, a bidentate XB acceptor, the iodine atoms are halogen bonded to the pyridine nitrogen atoms forming a one-dimensional ribbon of calixarenes alternated by two 4,4′-bipyridine units. These supramolecular architectures are the first example of solid-state networks of calixarene derivatives where the self-assembly is mostly driven by XBs.