6533b851fe1ef96bd12a9616

RESEARCH PRODUCT

Tetra-CMPO-derivatives of calix[4]arenes fixed in the 1,3-alternate conformation

Frederic BrisachVolker BöhmerAlessandro CasnatiFrançoise Arnaud-neuJaouad HaddaouiCrenguta DordeaMichael Bolte

subject

LanthanidebiologyInorganic chemistryGeneral ChemistryCrystal structurebiology.organism_classificationChloridechemistry.chemical_compoundchemistryCalixarenePolymer chemistrymedicineTetraTitrationMethanolMethylenemedicine.drug

description

Calix[4]arene derivatives fixed in the 1,3-alternate conformation and substituted at one side by four carbamoylmethylphosphine oxide (CMPO) residues were synthesised. Two CMPO groups are directly attached to the wide rim, while the second pair is bound to the narrow rim via a tri- or tetramethylene spacer. Similar compounds, in which two CMPO groups at the wide rim are combined with two picolinamide groups or two ionisable carboxylic groups at the narrow rim, were also prepared. Some of these calixarene derivatives were studied as extractants for lanthanides (La3+, Eu3+, Yb3+) and thorium (Th4+) from acidic solution into methylene chloride. For selected samples, stability constants in methanol were determined by spectrophotometric titrations. Three compounds (1b′, 13, 17) in the 1,3-alternate conformation and one intermediate in the cone conformation (18) were confirmed by a crystal structure.

https://doi.org/10.1080/10610271003678511