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The synthesis of novel crown ethers, part ix, 3‐phenyl chromenone‐crown ethers

“…However, 7,8-dioxa derivatives have exhibited CEFS upon cation complexing while the 6,7-dioxa-chromenones gave CEQFS as they are complexed in AN. Similar behaviours were also observed from other derivatives of such chromophore structures in our earlier studies [8][9][10]. The Synthesis of Novel Crown Ethers EXPERIMANTAL The starting chemicals were from MERCK or FLUKA unless otherwise cited.…”

“…The Synthesis of Novel Crown Ethers EXPERIMANTAL The starting chemicals were from MERCK or FLUKA unless otherwise cited. Initial compounds, 1c -1d were available from our earlier studies [8][9][10][11]. IR spectra were taken as KBr pellets with a JASCO FT-IR spectrometer, model-5300.…”

“…The crown ether derivatives of the 4-H and 4-methyl-6,7-dihydroxy-and -7,8-dihydroxycoumarins displayed the binding effect of alkali cations on the fluorescence emission spectra. They exhibited good agreements on the cation radii and the macrocyclic molecule size as reported [8][9][10]. The chromophore ethers were mostly capable of displaying the effect of the cation via UV-VIS spectra due to the restriction on the π-electron flow [11].…”

“…We have recently synthesised various crown ethers with different chromophore moieties and reported their cationic interactions using steady state fluorescence spectroscopy in acetonitrile [8][9][10]. The crown ether derivatives of the 4-H and 4-methyl-6,7-dihydroxy-and -7,8-dihydroxycoumarins displayed the binding effect of alkali cations on the fluorescence emission spectra.…”

“…The present work deals with the preparation of the novel crown ethers bearing 3-phenylcromenone moieties, which were studied with fluorescence spectroscopy to investigate cation complex formation with Li + , Na + , K + , and Rb + perchlorates [8][9][10][11].…”