Application of Calixarenes as Macrocyclic Ligands for Uranium(VI): A Review

Table 1

The structures of noncyclic analog 1 and calixarene derivatives 2–34.

𝑛 = 6–8; R = e.g., H, CH2OH; x, y = e.g., H, alkyl
𝑛 = 2–8; R = R′, CONH(OH); X = H, R′′ or SO3M; R′, R′′ = lower hydrocarbon; M = H or monovalent metal
R𝑛 = H, halogen, acetyl, amino, phosphate, nitro, sulfate, carboxyl, carboxylic, thiocarboxylic, carbamate, thiocarbamate radical, alkyl C1–C60, alkenyl C2–C60, alkynyl C2–C60, cycloalkyl C13-C12, cycloalkyl with at least one ethylenic or acetylenic unsaturation, aryl, naphthyl, aryl(C1–C30 Alkyl), (C1–C30 Alkyl)Aryl, and R1 = R2 = R3 or R1 = R2≠ R3 or R1≠ R2 = R3 or R1≠ R3 = R2 or R1≠ R3≠ R2.