Synthesis and Photochromism of Novel Chromene Derivatives Bearing a Monoazacrown Ether Moiety

Ahmed, Saleh; Tanaka, Mutsuo; Ando, Hisanori; Iwamoto, Hitoshi; Kimura, Kazuhiro

doi:10.1002/ejoc.200300070

Cited by 30 publications

(18 citation statements)

References 37 publications

(14 reference statements)

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“…9-15 However, the synthesis and properties of benzochromenes containing ionophoric fragments are poorly studied: only several crown con taining benzochromenes were described. [16][17][18] The syn thesis of benzochromenes with ionophoric fragments is not only of theoretical interest but can induce the prepa ration of new optical sensors for metal cations, photo switchable extracting complexones, and metal cation car riers through membranes.…”

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confidence: 99%

Synthesis and complexation properties of photochromic benzochromenes containing aza-and diaza-18-crown-6-ether fragments

et al. 2006

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Complex formation of Mg 2+ , Ba 2+ , and Pb 2+ perchlorates with 3,3 diphenyl 3H benzo[ f ]chromenes containing aza and diaza 18 crown 6 ether or morpholine fragments was studied. The strong influence of the metal cations on the spectral characteristics of these organic ligands and on the kinetic of photochromic transformations was found. The results obtained were explained by the formation of carbonyl "capped" complexes of various struc tures.

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confidence: 99%

Synthesis and complexation properties of photochromic benzochromenes containing aza-and diaza-18-crown-6-ether fragments

et al. 2006

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“…As seen, straight ring size-dependent selectivity of the crown moieties was not observed, Li þ , Ca 2þ and, to a less extent, Na þ were preferred by both ligands. Other NP dyes containing 12-crown-4, 15-crown-5 and 18-crown-6 moieties were reported to show some size-dependent cation discrimination for Li þ vs Na þ with enlargement of the crown ring [24]. Our ligands, comprised of a 17-crown-5 (4a) and a 23-crown-7 (4b) binding site with twisted binaphthyl subunit, cannot provide ideal steric environment for complexation, therefore only part of the donor atoms can be involved in binding.…”

Section: Photochromism Of Crowned Naphthopyrans 4ab With Metal Ionsmentioning

confidence: 99%

“…(Fig. 1) Due to the easy light fatigue of spirobenzopyrans (SP) [23], our studies were extended to spironaphthoxazines (NO) [8,23] and naphthopyrans (chromens, NP) [24,25] because of their greater resistence to photodegradation. The UV light induced ring opening of the colorless NO and NP photochromes is similar to that of SP (C -O cleveage), but here quinoidal and not zwitterionic structure of the open forms is responsible for the coloration [26,27] (Fig.…”

Section: Introductionmentioning

confidence: 99%

“…In contrast, crowned NP molecules were published to resist to alkali cation-facilitated thermal isomerization, while Ca 2þ and Mg 2þ induce moderate coloration. Upon UV irradiation, however, the opening of the pyran ring of NP dyes was markedly facilitated by alkali-and alkaline earth metal cations as well [23,24]. Consequently, the crowned SP, NO and NP molecules are regarded as special chromogenic receptors of dual character.…”

Section: Introductionmentioning

confidence: 99%

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1,1'-Binaphtho(aza)crowns Carrying Photochromic Signalling Unit, I: Synthesis, Characterization and Cation Recognition Properties

Kőszegi

Grűn

Bitter

2006

Supramolecular Chemistry

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S)-1,1'-Binaphtho(monoaza)crown-5,-6 and-7 ionophores carrying photochromic indolospirobenzopyran (SP), naphthoxazine (NO) and naphthopyran (NP) signalling groups were synthesized and their cationinduced isomerisation to the colored merocyanine or quinone forms was studied by UV/Vis spectroscopy in the presence of alkali and alkaline earth metal ions. Under dark conditions the equilibrium of SP and NO dyes were remarkably shifted to the colored form by cations of high positive charge density (Li 1 and alkaline earth metal ions). The same effects were observed with crowned NPs after UV irradiation. The stability of some merocyanine-cation complexes were evaluated by calculating the kinetic parameters of the coloration process.

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“…The process is most effective if the sizes of the crown ether cavity and the metal ion are in the optimum ratio.Irradiation of the compounds 81 and 82 in the region of the long-wave absorption band of the merocyanine form leads to the formation of the initial spiro form and a released metal ion, making it possible to control the complex formation process by irradiation. reaction of the chromenes 84-86[119][120][121] involves cleavage of the C-O bond by the action of light with the formation of the open form B. At room temperature the reaction is reversible.…”

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Organic chemosensors with crown-ether groups (review)

Цуканов

Дубоносов

Breń

et al. 2008

Chem Heterocycl Comp

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Recent advances in the chemistry of organic chemosensors containing crown-ether groups are reviewed.Organic chemosensors are molecules of abiotic nature capable of interacting selectively and irreversibly with a specific substrate (ion, molecule) with corresponding changes in one or more characteristics of the system. A series of reviews have described methods for the synthesis of chemosensors [1] and their use in the determination of metal cations [2-8], anions, and molecules [4, 9, 10]. Some of them treat the various types of fluorescent chemosensors [5][6][7][8] or photoswitching compounds [11][12][13][14] selectively. In this review, based exclusively on the results of recent years, sensors containing crown-ether groups are examined. Special attention is paid to the various mechanisms of action of crown-containing chemosensors, which are classified according to their electronic and photochemical characteristics.In the general case a chemosensor molecule consists of signal and receptor parts with a bridge between them although the latter may be absent. As a rule chemosensors can be subdivided into chromogenic, fluorescent, and photoswitchable.During the interaction of a chromogenic sensor with the substrate (in particular with a metal ion) a hypsochromic or bathochromic shift of the long-wave absorption band of the initial compound is observed. If the shift of the bands is significant and takes place in the visible part of the spectrum it leads to a visually discernable change in the color of the solution. Such signal systems are usually called colorimetric or "naked-eye" chemosensors.The action of fluorescent chemosensors is based both on change of the fluorescence intensity and on shift of the emission band of the initial compounds during the formation of a complex with the substrate.Photoswitchable chemosensors are capable of reversible "switching on-switching off" of their sensor characteristics under the influence of light.Among ionophore-receptors capable of combining with positively charged ions, it is possible to include chelating agents, podands, coronands (or crown ethers), cryptands, calixarenes, cyclodextrins, etc. [15].Crown ethers, discovered by Pedersen in 1962, occupy a special position among receptors and are widely used in the design of new chemosensors based on their unique ability to combine with the cations of alkali metals, their fairly high selectivity, and their accessibility. In addition to alkali metals, crown ethers are also effective complexing reagents for the cations of alkaline-earth metal, Pb 2+ , and Tl 2+ , and when nitrogen and sulfur atoms are inserted into their structure they become sensitive to Ag + , Hg 2+ , and Cd 2+ ions. The __________________________________________________________________________________________

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Synthesis and Photochromism of Novel Chromene Derivatives Bearing a Monoazacrown Ether Moiety

Cited by 30 publications

References 37 publications

Synthesis and complexation properties of photochromic benzochromenes containing aza-and diaza-18-crown-6-ether fragments

Synthesis and complexation properties of photochromic benzochromenes containing aza-and diaza-18-crown-6-ether fragments

1,1'-Binaphtho(aza)crowns Carrying Photochromic Signalling Unit, I: Synthesis, Characterization and Cation Recognition Properties

Organic chemosensors with crown-ether groups (review)

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