Synthesis and characterization of bisphenol-A copolyethers and copolyesters carrying calix[4]arene units in the main chains and their binding properties towards silver cations

Abstract

SUMMARY: A modified interfacial polycondensation between bisphenol-A and 1,3-dimethoxy lower-rim substituted calix [4]arene derivatives with dibromomethane in the presence of tetrabutylammonium hydrogen sulfate as phase transfer catalyst (PTC) leads to copolyethers with variable M -w values depending on the reaction temperature and the amount of PTC. The calix [4]arene content in the polymer chains depends on the phenolic monomer ratios. The polycondensation reaction of the same comonomers with terephthaloyl chloride but in the absence of the above PTC affords the corresponding copolyester. The soluble fraction of this polymeric material in CHCl 3 showed M -w of ca. 21 000 and a variable calix[4]arene content depending on the phenolic monomer ratio as well. The binding properties of the copolyethers toward silver ions are ten-fold higher than those of a model tetraalkoxy calix [4]arene derivative. It is suggested that this increased receptor ability is due to the change of the original cone conformation of the macrocyclic monomer into the partialcone conformation by incorporation in the polymer.

Selective complexation and extraction of Ag(i) and Zn(ii) versus Pb(ii) by polymer beads modified by attachment of a bipyridyl–calixarene-based chelate

“…25,26 As they offer a wide range of structural and functional modulations, the calixarene platforms [27][28][29][30][31][32] are subjected to intense investigations in particular for the building of highly organized metal chelators, with objectives of separation, purification, waste depollution. [33][34][35][36][37][38][39] Some of them have been introduced into polymeric systems, as building-blocks, [40][41][42][43][44][45][46][47] or as appended chelating arms. For the latter, recent examples deal with covalent attachment of various calix [4]arene podands for preconcentration/separation of various metal ions.…”

“…48 Inorganic or organic supports have been employed, such as TiO 2 , 49 silicagels or polysiloxanes, [50][51][52][53][54][55][56][57] Merrifield resin, [58][59][60][61][62][63][64][65][66] amino polymers derivatives, [67][68][69][70][71] polyesters, 72,73 Amberlite-XAD, 50,74 Wang benzaldehyde resin, 75 dextran, chitosan or cellulose. [76][77][78][79] More precisely, some of these contributions are related to the complexation/extraction of silver(I), alone or in mixtures of metal ions, 40,41,46,47,77 silver(I) and lead(II), 47 lead(II) and zinc(II). 42,43,45,50,54,55,57,59,61,[66]…”

Complexation of silver and co-recovered metals with novel aza-crown ether macrocycles by electrospray ionization mass spectrometry

“…The binding properties of the ligands play critical roles in the ability to target specific metals of interest, and thus there are many strategies for designing compounds with the appropriate selectivity, such as for silver, a metal that has numerous practical uses. Several ongoing studies are investigating the complexation properties of silver with ligands containing nitrogen, sulfur and oxygen heteroatoms, such as heterocyclic amines, 17,18 calixarene derivatives and other macrocycles, [19][20][21][22][23][24] thiolates, 25 and unsaturated polymers. 26 Also, new ligands are being developed for aqueous extraction 27 of silver and for speciation and removal of silver from natural waters.…”

Synthesis of fully lower‐rim, carbonate‐bridged calix[8]arenes and their curing behavior

“…Their inclusion properties can be modified by lower‐rim (hydroxyl groups) modification by esterification, etherification, conversion to amines or thiols, and so forth 7–12. They have acquired unique applications in analysis probes,13 membranes,14 decontaminating agents for wastewater,15 dendrimers,16 high‐performance polymers,17 curing agents,18, 19 and so forth 20. Lower‐rim bridging (linkage between hydroxy groups) has enabled the introduction of another macrocyclophane into the parent calixarenes 21–23.…”