Synthesis and binding properties of calix[4]arene telomers

Synthesis and binding properties of two polymeric thiacalix[4]arenes

“…From the results given in Table 1, it has been observed that oligomer 4a shows significant extraction ability toward alkali metal cations, whereas the other compounds (1-3) are ineffective for alkali metal cations in the liquid-liquid extraction systems (Fig. 1), and 4b can be a good adsorbent for alkali metal cations in the solid-liquid batchwise adsorption systems, very likely because of the structural and collective/cooperative behavior of thiacalix [4]arene moieties where the amide bridges and polymeric groups may also play an important role in this situation, which agreed with our previous results [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. Table 2 shows that MerrifieldÕs polymer 5 is ineffective for alkali metal cations in the solid-liquid systems.…”

“…The solutions were then magnetically stirred in a thermostated water-bath at 25°C for 1 h, and finally left standing for an additional 30 min. The concentration of picrate ion remaining in the aqueous phase was then determined spectrophotometrically as previously described [39][40][41][42]. Blank experiments showed that no picrate extraction occurred in the absence of calixarene.…”

“…As the applications of chemically modified calixarenes/thiacalixarenes, several researchers have attempted to prepare various extractants and chelating adsorbents for alkali/transition metal cations and anions, either by transforming into oligomeric/polymeric structures or by immobilizing them onto solid support materials [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51]. Although quite a number of reports exist on monomeric thiacalixarenes as mentioned above, those on the oligomeric/polymeric thiacalixarenes are very limited.…”

Removal of azo dyes from aqueous solutions using calix[4]arene and β-cyclodextrin

“…These mechanisms are, in general, complicated because they may involve several different interactions [45,48,49]. Some of the reported interactions include: ion-exchange, complexation, coordination/chelation, electrostatic interactions, acidebase interactions, hydrogen bonding, hydrophobic interactions, and physical adsorption.…”

The synthesis and metal cation extraction studies of novel polymer-bound calix(aza)crowns

“…The interesting properties shown by these cyclic oligomeric molecules stimulated the exploitation of useful methods towards their incorporation into polymeric matrices, which are interesting for the development of ion selective electrodes and membranes, chemical and biochemical sensors and selective extraction of ions and neutral molecules [15][16][17][18][19]. Previously, to increase the affinity of calixarenes toward metal ions and anions, two main strategies have been followed: first, different ionophoric groups including carbonyl, amide, and nitrile have been incorporated onto the calixplatform; second, the calixarene units have been fixed in a polymeric matrix [20][21][22][23][24][25][26][27][28][29]. We have also reported the synthesis of calix(aza)crowns and their corresponding oligomers along with their extraction behavior towards toxic metal cations [30].…”