Effect of an alkyl substituent and spacer length in benzene-centered tripodal diglycolamides on the sequestration of minor actinides

Three benzene-centered tripodal diglycolamide (Bz-T-DGA) ligands, where diglycolamide (DGA) moieties are tethered to the central benzene ring through a methylene spacer and having either a hydrogen atom (LI) or an isopentyl group (LII) attached to the N-atom, and DGA moieties attached via an ethylene spacer and having an isopentyl group attached to the N-atom (LIII), were studied for their complexation and extraction abilities towards trivalent actinides and lanthanides. The distribution ratio of Am(iii) and Eu(iii) with 1 mmol L-1 ligand in 5% iso-decanol/n-dodecane followed the order: LII > LIII > LI. The substitution of the H atom with the isopentyl group on the N-atom of the DGA moieties resulted in two orders of magnitude enhancement in the extraction ability of the ligand. On the other hand, increase in the spacer length between the benzene ring and the DGA moieties resulted in several fold reduction in the extraction ability of the ligand. Spectroscopic studies with Eu3+ ions in acetonitrile also confirmed the metal/ligand complex formation constant in the order: LII > LIII > LI. Luminescence decay lifetimes of Eu3+/ligand complexes confirmed the absence of water molecules and that all the primary coordination sites of the metal ion are occupied by the ligands.

Benzene-centered tripodal diglycolamides: synthesis, metal ion extraction, luminescence spectroscopy, and DFT studies

Three benzene-centered tripodal diglycolamides (Bz-T-DGAs) were synthesized and evaluated for actinide, lanthanide, and fission product ion extraction.

Synthesis and self-assembly of carbamoylmethylphosphonate acrylamide-based diblock copolymers: new valuable thermosensitive materials

We report the synthesis by RAFT polymerization of well-defined diblock copolymers bearing carbamoylmethylphosphonate moieties which proved to sorb gadolinium. These poly(diethyl-6-(acrylamido)hexylcarbamoylmethylphosphonate-b-acrylic acid) (P(CPAAm6C-b-AA)) copolymers were able to self-assemble as a function of temperature, above their cloud point value.

The first report on phosphonate-based homopolymers combining both chelating and thermosensitive properties of gadolinium: synthesis and evaluation

Original thermoresponsive poly(acrylamide) bearing valuable carbamoylmethylphosphonate moieties was prepared for gadolinium sorption.

Synthesis and f-element ligation properties of NCMPO-decorated pyridine N-oxide platforms

Syntheses of hybrid N-attached CMPO decorated pyridine N-oxide ligands, computational, spectroscopic and structural characterization of their coordination interactions with lanthanide ions and survey solvent extraction analyses are described.

Novel types of tripodal CMPO ligands: synthesis and extraction

Novel tripodal CMPO ligands having either aryl groups at the N-atom or alkyl groups at the CMPO methylene bridge were prepared in good yields. In the latter case one alkyl group per CMPO moiety was selectively introduced. Extraction studies with Am3+ and Eu3+ show that there is an influence of the electronic character of the aryl groups on the extraction. Alkylation of the CMPO methylene group gives rise to a considerable decrease of the D-values (about 100–1000 times), dependent on the bulkiness of the alkyl substituent.