Showing papers in "Organic Letters in 2008"

TL;DR: Control experiments support a radical-based mechanism and suggest radical processes may be partially involved in the reported transition-metal-catalyzed arylation reactions employing t-butoxide bases and haloarenes under elevated temperatures or under microwave irradiation.

TL;DR: A coumarin-based fluorescent chemodosimeter with a salicylaldehyde functionality as a binding site has been developed for selective detection of cyanide anions over other anions in water at biological pH.

TL;DR: A novel distyryl-substituted boradiazaindacene (BODIPY) dye displays interesting properties as a sensitizer in DSSC systems, opening the way to further exploration of structure-efficiency correlation within this class of dyes.

TL;DR: A visible near-infrared chemosensor for mercury ions was successfully devised and characterized and its high selectivity towards mercury ions over the other competitive species makes the "naked-eye" detection of mercury ions possible.

TL;DR: Catalytic amounts of aromatic carboxylic acid MesCO H enabled efficient ruthenium-catalyzed direct arylations in apolar solvents with unparalleled broad scope via a concerted deprotonation-metalation mechanism.

TL;DR: Stille coupling of regioisomerically pure dibromonaphthalene bisimides (NBI) with various stannylated thiophene-based monomers yields (very) high molecular weight donor-acceptor conjugated polymers.

TL;DR: A fluorescent probe, HKOCl-1, has been successfully developed for the detection of hypochlorous acid on the basis of a specific reaction with p-methoxyphenol and might be used as an efficient tool for probing the roles HOCl plays in biological systems.

TL;DR: Two new tetraphenylethylene (TPE) compounds 1 and 2 bearing adenine and thymine moieties were found to be fluorescence "turn on" chemosensors for Ag(+) and Hg(2+) by making use of the AIE feature of TPE motif and the specific binding ofadenine/thymine with Ag(+)/Hg( 2+).

TL;DR: The palladium-catalyzed oxidative vinylation of indole-3-carboxylic acids with alkenes effectively proceeds via directed C-H functionalization and decarboxylation to produce the corresponding 2-vinylated indoles.

TL;DR: A novel "naked-eye" and ratiometric fluorescent zinc sensor (AQZ) of carboxamidoquinoline with an alkoxyethylamino chain as receptor was designed and synthesized and shows good water solubility and high selectivity for sensing.

TL;DR: 4-(1H-phenanthro[9,10-d]imidazol-2-yl)benzaldehyde 1 was rationally designed as a novel ratiometric fluorescent probe for cysteine and homocysteine, notably, the probe displayed a very large (125 nm) hypsochromic shift in emission due to switching off intramolecular charge transfer.

TL;DR: N-heterocyclic carbenes were demonstrated to be efficient catalysts for the Staudinger reaction of ketenes with N-tosyl, N-benzyloxycarbonyl, or N-tert-butoxy Carbonyl imines, and two possible catalytic pathways, initiated by the addition of NHC to ketenes or imines were discussed.

TL;DR: Inexpensive copper catalysts enabled modular one-pot multicomponent syntheses of fully decorated triazoles through a sustainable "click" reaction/direct arylation sequence.

TL;DR: A Hg(2+)-selective rhodamine 6G derivative bearing thiolactone moiety was synthesized, and its crystal structure with HG(2+) is presented to explain the binding mode.

TL;DR: A novel boradiazaindacene derivative to detect cyanide ions in solution at micromolar concentrations is developed and displays a large decrease in emission intensity and a reversible color change from red to blue on contact with cyanide ion.

TL;DR: In this paper, a rhodium-catalyzed chelation-assisted C-H activation of alpha, β-unsaturated ketoximes and the reaction with alkynes to afford highly substituted pyridine derivatives is described.

TL;DR: Generated in nine steps from a glucose analogue, DIMAC reacted with azide-labeled proteins and cells similarly to cyclooctynes, however, its superior polarity and water solubility reduced nonspecific binding, thereby improving the sensitivity of azide detection.

TL;DR: In this article, the ortho arylation of anilides to form biphenyls via a twofold C−H functionalization/C−C bond-forming process is described.

TL;DR: A new fluorescent turn-on probe for the selective sensing and bioimaging of thiols is reported and excellent immunity to interference from nitrogen and oxygen nucleophiles is demonstrated.

TL;DR: Using propiolic acid as a difunctional alkyne and using the consecutive reactions of the Sonogashira reaction and the decarboxylative coupling, unsymmetrically substituted diaryl alkynes were obtained in moderate to good yield.

TL;DR: Cultivation of an obligate marine Streptomyces strain has furnished the marinopyrroles A and B, densely halogenated, axially chiral metabolites that contain an uncommon bispyrrole structure that possess potent antibiotic activities against methicillin-resistant Staphylococcus aureus.

TL;DR: This method features the use of a novel catalytic system consisting of 10 mol % of Pd(II), 50 mol% of Cu(I), and 2 equiv of Bu4NBr that produced variously substituted benzothiazoles in high yields with good functional group tolerance.

TL;DR: A magnetically separable palladium catalyst was simply synthesized through a wet impregnation incorporating palladium nanoparticles and superparamagnetic Fe3O4 nanoparticles in KBH4 solution, which is a highly efficient catalyst for the carbonylative Sonogashira coupling reaction of aryl iodides with terminal alkynes under phosphine-free conditions.

TL;DR: A novel distyryl-substituted boradiazaindacene (bodipy) dye with an emission peak moving hypsochromically from 730 to 680 nm on Zn(II) ion binding seems to be promising as one of the very few water-soluble fluorescent chemosensors emitting in the near IR region.

TL;DR: A series of new fluorescent probes bearing tren-spaced rhodamine B and dansyl groups have been synthesized and compound 1 shows the best FRET efficiency throughdansyl emission to rhodamines absorption for the Cu2+ ion.

TL;DR: It has been demonstrated that FD7 can be used as a fluorescent probe for monitoring Cr(3+) in living cells by means of confocal laser scanning microscopy experiments.

TL;DR: A variety of substituted benzotriazoles have been prepared by the [3 + 2] cycloaddition of azides to benzynes under mild conditions, affording a rapid and easy entry to substituted, functionalized benzotRIazoles under mild circumstances.

TL;DR: Nanosized platinum particles dispersed on platelet-type CNF efficiently catalyze the reduction of functionalized nitroarenes to the corresponding substituted anilines in high turnover numbers with other functional groups remaining intact.

TL;DR: A protocol for forming a highly active PD(0) catalyst from Pd(OAc) 2, water, and biaryldialkylphosphine ligands has been developed and exhibits excellent reactivity and efficiency in the coupling of a variety of amides and anilines with aryl chlorides.

TL;DR: A coumarin-based colorimetric chemosensor 1 exhibits good sensitivity and selectivity for the copper cation over other cations both in aqueous solution and on paper-made test kits.