Extraction of technetium(vii) by calix[4]arene tetraketones and tetraesters from acidic and basic media

Synthesis, Structure, and Exctraction Ability of Tetrasubstituted Thiacalix[4]Arenes with Crown Ether Fragments on the Lower Rim

“…Aqueous solutions of picrates (4 ml), which contain excess metal hydroxide, and the solutions of the compounds under study in CH 2 Cl 2 (4 ml) were stirred for 60 min at ~20°C and kept for 90 min for phase separation. Initial concentrations of ligand in organic phase and metal hydroxide and picrate in aqueous phase corresponded to [5][6][7] …”

“…[2][3][4] Substitution of methylene bridges for sulfur atoms results in the macrocycle size increase and the formation of new receptor properties for thiacalixarene derivatives. [4][5][6][7][8][9][10][11][12][13] Potentiometric sensors based on thiacalix [4]crown ethers 2b in poly(vinyl chloride) membrane electrodes have the detection limit of cesium cations less than 10 −7 M; [16] compounds 1b with pyridylmethyl substituents in 1,3-alternate conformation [17] demonstrate the ability to switchable recognition of lithium and silver cations; 1b with methoxy and propoxy groups extract selectively potassium and rubidium cations. [18] Size of thiacalixarene platform is the key parameter [14] to control the complexation ability of derivatives 2b towards alkali metal ions.…”

Thiacalix[4]arenes with Triple Bonds at the Lower Rim: Synthesis and Structure

“…[2,15] Accordingly, several groups have investigated [15,[16][17][18] the functionalization of (thia)calixarenes 1-4 by alkyl halides using the acetone(acetonitrile)/M 2 CO 3 reaction system (M ≡ Na, K, and Cs). As a part of our research into the derivatization of lower rim of these macrocycles, [3,[19][20][21][22][23][24][25][26][27][28][29][30][31] a systematic study of the reaction of thiacalix [4]arene 3 and p-tert-butylthiacalix [4]arene 4 with propargyl bromide in the presence of alkali metal carbonates (Scheme 1) was carried out. Obtained data are summarized in the Table 1.…”

Sorbents based on calix[4]arenes for extraction of technetium(vii) from acidic and alkaline media

“…It is known that technetium(VII) is efficiently extracted from aqueous solutions in a wide pH range by polymer sorbents containing groups of macrocyclic compounds, including calix[n]arenes and thiacalix [4]arenes. 2,3,4 A whole series of complexation agents based on calix [4]arenes capable of binding diverse cations with great selectivities has been synthesized in recent years.…”

“…2,3,4 A whole series of complexation agents based on calix [4]arenes capable of binding diverse cations with great selectivities has been synthesized in recent years. 5, 6 In this connection, for the sorption of Tc VII we proposed polymer sorbents of the new type, which are rather simply prepared by the noncovalent immobilization of calix [4]arenes on the polymer Amberlite XAD 7 TM that has proved an ade quate support.…”