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 M̄w 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 CHCl3 showed M̄w of ca. 21000 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 partial-cone conformation by incorporation in the polymer. © Wiley-VCH Verlag GmbH, 1999.
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
DONDONI, Alessandro;MARRA, Alberto;
1999
Abstract
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 M̄w 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 CHCl3 showed M̄w of ca. 21000 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 partial-cone conformation by incorporation in the polymer. © Wiley-VCH Verlag GmbH, 1999.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
