140862-52-8Relevant articles and documents
Calixarene-based porous 3D polymers and copolymers with high capacity and binding energy for CO2, CH4and Xe capture
Bezuidenhout, Charl X.,Bracco, Silvia,Comotti, Angiolina,Pedrini, Alessandro,Perego, Jacopo,Sozzani, Piero
supporting information, p. 27353 - 27360 (2021/12/24)
The supramolecular capacity of calixarenes towards guests is largely consolidated; in contrast, the synthesis of porous calixarene-based frameworks by covalent bond formation is still a challenge. Our target was to yield 3D polymers and copolymers based on calixarenes for selective gas-capture, endowed with easy pore accessibility and specific sites, and builtviaa straightforward synthetic route. The covalent calixarene frameworks (CXFs) were prepared by the Yamamoto coupling reaction starting from tetrabromo calixarene propoxy- and methoxy-monomers of three stable calixarene (partial cone, effective cone, and 1,3-alternate) conformers and complete post-synthetic deprotection to achieve polar phenolic calixarene derivatives. Moreover, the copolymer of calixarene-based monomers with tetrabromo-tetraphenylmethane exhibited remarkable surface area up to about 3000 m2g?1. Smart architectures endowed with hierarchical porosity from micro- to meso-porosity showed notable sponge-like swellability by CO2, which was captured effectively at room temperature, even in competition with N2, yielding CO2removal in column breakthrough experiments. Indeed, CXFs displayed excellent CO2and CH4energy binding of 35 and 24 kJ mol?1, respectively. Ultramicropore sites were highlighted by Xe capture andin situdetection after a xenon diffusion time of a few milliseconds, by laser-assisted hyperpolarized129Xe NMR, revealing the accessibility of calixarene capsules and the available space. This synthetic route demonstrated the possibility to modulate at will the pore capacity and selectivity, displaying porous frameworks with two distinct pore families, wherein calixarene moieties play the role of small and selective sites. A contractile behavior of the frameworks was observed upon deprotection which produced more polar sites, due to the formation of hydrogen bond networks.
Cyanocalix[4]arenes: Synthesis, crystal structures and reactivity studies
Applewhite, Malcolm J.,Haynes, Delia A.,Arnott, Gareth E.
, p. 475 - 484 (2016/04/19)
Herein, we describe an improved method to synthesise mono-, di- and tetra-cyanocalix[4]arene and report their crystal structure determinations. We also report our attempts to further functionalise the cyanocalix[4]arenes into dithiadiazolyl-calix[4]arenes
Synthesis and investigation of catalytic affinities of water-soluble amphiphilic calix[n]arene surfactants in the coupling reaction of some heteroaromatic compounds
Sayin, Serkan,Yilmaz, Mustafa
, p. 6528 - 6535 (2016/09/23)
Six water-soluble calix[n]arene-based Br?nsted acid-type catalysts with amphiphilic groups were successfully synthesized by incorporating sulfonic acid moieties. Their structures were characterized using FTIR,1H NMR,13C NMR, APT-NMR, and elemental analysis techniques. Moreover, their catalytic capabilities were evaluated in the coupling reaction of 2-methylfuran and/or N-methylindole with some sec-alcohols in aqueous media. The association of their surfactant abilities, and the effects of water amount used and reaction durations on the catalytic activities of these amphiphilic calix[n]arene derivatives were also investigated. Observations indicated that these amphiphilic calix[n]arene catalysts exhibited high catalytic activities in the coupling reactions of 2-methylfuran and N-methylindole with some alcohols in water.
