The fluorescence enhancement of the probe molecule 1-anilino-8-naphthalenesulfonate (ANS) by a number of modified beta-cyclodextrins has been studied. Alkyl-and hydroxyalkyl-substituted beta-cyclodextrins show significantly greater enhancement of ANS fluorescence than does the parent unmodified beta...

Abstract: This paper describes the host properties of a new cucurbit[6]uril analogue, studied by fluorescence and 1H NMR spectroscopy. This host has an elongated cavity with oval-shaped portals. It is intrinsically fluorescent, and more importantly, this fluorescence is sensitive to guest encapsulat...

Addition of hydroxypropyl-beta-cyclodextrin to o-phthalaldehyde (OPA)-amino acid-thiol reaction mixtures is shown to cause significant enhancement of the fluorescence of the isoindole product for a wide range of amino acids, with the largest effects observed in the cases of glycine and lysine. The l...

The fluorescent molecules 1-anilinonaphthalene-8-sulfonate (1,8-ANS) and 2-anilinonaphthalene-6-sulfonate (2,6-ANS) are extremely sensitive to the polarity of their local environment, making them excellent probes for the study of heterogeneous systems, including cyclodextrin (CD) solutions. Both are...

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The fluorescence intensity of 7- methoxycoumarin (7MC) in aqueous solution is found to significantly decrease upon addition of various cyclodextrins. This observed phenomenon is described as fluorescence suppression, to distinguish it from fluorescence reduction via bimolecular quenching. The decrea...

Abstract: Laser flash photolyses of 2-, 3-, and 4-diazoacetylpyridines 8 give the corresponding pyridylketenes 7 formed by Wolff rearrangements, as observed by time-resolved infrared spectroscopy, with ketenyl absorptions at 2127, 2125, and 2128 cm-1, respectively. Photolysis of 2-, 3-, and 4-8 in C...

Abstract: The title ketene 2 has been generated by laser flash photolysis and observed in solution for the first time, using time-resolved infrared spectroscopy. The kinetics of the reactivity of 2 with H2O, MeOH, and Et2NH with relative reactivities of 1.0, 2.0, and 73 have been measured. These are...

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Abstract: This work describes the fluorescence enhancement of the probes 2,6- and 1,8-ANS via complexation with the macrocyclic host cucurbit[7]uril (Q7). The association of these two guests with the Q7 host has been studied using fluorescence, 1H NMR spectroscopy, and molecular modeling. In the cas...

Intercalation compounds of pyrene and 8-anilino-1-naphthalenesulfonic acid into MoS2 have been synthesized and characterized. This was achieved by using the exfoliation/re-stacking properties of LiMoS2. The degree of intercalation was found to be dependent on the amount of guest species used, the re...

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Laser flash photolysis of 9-hydroxy-9-fluorenecarboxylic acid in hexafluoro-2-propanol (HFIP) generates a transient with lambda(max) at 495 nm that reacts with nucleophiles such as methanol and bromide and is insensitive to oxygen. In the presence of 0.15 M trifluoroacetic acid, a different transien...

Abstract: A solid precipitate is formed immediately upon the mixing of aqueous salt solutions of the fluorescence probe 1-anilino-8-naphthalenesulfonate (1,8-ANS) and the cage compound cucurbituril. The resulting solid compound is highly fluorescent, with a maximum emission at ca. 478 nm. Single cry...

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Abstract: The interconversion of cyclobutene-1,2-diones (1) and 1,2-bisketenes (RC=C=O)2 (2) has been surveyed for different combinations of substituents R = H, Me, t-Bu, Ph, Me3Si, CN, Cl, Br, R1O, alkynyl, and PhS. The bisketenes 2 have been generated by flash photolysis, and the kinetics of their...

The polarity-sensitive fluorescent dye Nile Red forms association complexes with various cyclodextrins in aqueous solution. The formation of such association complexes has a significant effect on the Nile Red fluorescence, with the largest effect being observed in gamma-cyclodextrin solution. When g...

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The effect of alpha-, beta-, and gamma-cyclodextrin (CD) and their hydroxygropylated (HP) derivatives on the solubility and fluorescence of the compound curcumin has been studied. Curcumin, the main constituent of the Indian spice turmeric, is of growing interest due to its wide-ranging pharmaceutic...

We report the first use of fluorescence spectroscopy to probe the environment of the cavities that are present in open framework coordination polymers.