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Three 2-cyano boron-dipyrromethene (BODIPY) based derivatives ( CB1 – CB3 ) have been synthesized and characterized. The photophysical properties of these compounds are investigated by means of UV/Vis absorption and fluorescence spectroscopy. CB1 – CB3 exhibit small Stokes shift and high fluorescence quantum yield. Noticeably, CB2 with styrene moieties at 5-position of BODIPY displays absorption alternation with maximum of 120 nm red-shift upon addition of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) as a base, giving remarkable color change which can be detected by naked eye. Meanwhile, the compound CB3 shows high selectivity toward fluoride ion via fluorescence quenching mechanism by release of the masked phenolate form of CB2 through fluoride ion induced deprotection reaction. It also exhibits fast signal response time (30 s) and excellent selectivity over other competing analytes, making it a good candidate as colorimetric sensor for fluoride sensing. [ABSTRACT FROM AUTHOR]

A new probe PQ comprising quinoline as a fluorophore and 2-picolinic group as a recognition unit is designed and synthesized with high sensitivity and selectivity toward copper ion. The probe PQ shows almost no fluorescence in HEPES buffer (20 mM, pH 7.0), but displays obvious fluorescence enhancement after the addition of Cu 2+ , this response is considered to be attributed to the Cu 2+ -promoted hydrolysis of PQ to yield a highly fluorescent product, 2-methyl-7-hydroxy-quinoline with fluorescence signal greatly amplified. The probe PQ exhibits remarkable selectivity and sensitivity toward Cu 2+ and the detection limit is as low as 0.15 μM. These results reveal that PQ has the potential to discriminate Cu 2+ over other cations in neat aqueous solution by fluorescence turn-on response. In addition, the cell imaging experiment indicated the probe PQ can be used as a possible sensor to detect Cu 2+ in living cells. [ABSTRACT FROM AUTHOR]

The given text provides information about the synthesis and characterization of various compounds. The compounds were prepared using a general procedure and purified by flash chromatography. The yield, physical properties, and spectroscopic data of each compound are provided. The compounds synthesized include N-Cyclohexyl-N-methyl-4-((3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazin-7-yl)oxy)butanamide, 6-Methyl-2H-benzo[b][1,4]oxazin-3(4H)-one, 6-Ethyl-2H-benzo[b][1,4]oxazin-3(4H)-one, 6-Propyl-2H-benzo[b][1,4]oxazin-3(4H)-one, 6-Methoxy-2H-benzo[b][1,4]oxazin-3(4H)-one, 1-Oxa-4-azaspiro[4.5]deca-6,9-diene-3,8-dione, 7-Fluoro-2H-benzo[b][1,4]oxazin-3(4H)-one, and 6-Fluoro-2H-benzo[b][1,4]oxazin-3(4H)-one. [Extracted from the article]

A simple and efficient methodology for the synthesis of triphenylamines has been demonstrated using copper catalyst with a ligand and tripotassium phosphate as the base. The effect of parameters such as catalyst precursors, ligands, bases and solvents were studied and a series of triphenylamines were obtained with moderate to excellent yields in DMF. This reaction displays great functional groups compatibility in the presence of a broad range of functional groups. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) is a kind of gaseous signal molecule in many physiological processes. In order to detect H 2 S, a novel "turn on" fluorescent probe 6,12-dihydroxyperylene-1,7-dione (DPD) was designed and synthesized. The probe DPD is fluorescence silence, while the addition of H 2 S induces an obvious green fluorescence with an obvious color change from dark blue to yellow-green. The probe shows excellent selectivity, fast response (2.5 min) and linear curve (0–90 μM) in wide effective pH range (4–10). Competition experiments are also revealed in corresponding studies and the detection limit is 3.6 μM. The response mechanism is proved to be the reduction of the probe by H 2 S, which is confirmed by 1H NMR. Furthermore, through the fluorescence turn-on signal toward H 2 S in Hela cells, probe DPD was successfully applied to monitor H 2 S in living Hela cells. Unlabelled Image • A "turn-on" probe DPD for hydrogen sulfide was developed. • DPD shows highly selective and sensitive response to hydrogen sulfide. • DPD shows rapid response and high sensitivity toward hydrogen sulfide. • The response mechanism of the probe DPD with H 2 S was confirmed to be reduction of carbonyl groups to hydroxyl groups. • DPD can monitor the exogenous cysteine in solution and living cells. [ABSTRACT FROM AUTHOR]

• A new asymmetric nonfullerene acceptor SN-O is designed via a " dual asymmetric strategy ". • SN-O exhibits a large dipole moment and upshifted LUMO and HOMO energy levels. • More ordered molecular packing with enhanced crystallinity and fibril-like nanostructures are observed for the ternary blend. • A low nonradiative energy loss of 0.202 eV is achieved, which is among the lowest values for D18-based OSCs. The open-circuit voltage (V oc) of organic solar cells (OSCs) is still far from the Shockley-Queisser limit due to the large non-radiative voltage loss (Δ V oc nonrad). Reducing energy loss (E loss) to obtain higher V oc without sacrificing J sc and FF is the key to achieve further improvement in power conversion efficiency (PCE) of OSCs. In this work, we designed and synthesized a new asymmetric nonfullerene acceptor via a dual asymmetric strategy, named as SN-O. Under the synergistic effect of alkoxy chain and nitrogen atom substitution, the LUMO and HOMO energy levels of SN-O are significantly elevated compared to Y6, allowing SN-O to display a high open-circuit voltage with a reduced nonradiative energy loss (Δ E nonrad = 0.177 eV). The alkoxy side chain of SN-O brings an intramolecular conformational locking effect and the large dipole moment of asymmetric molecules facilitate the aggregation properties in thin films. The good miscibility allows Y6 and SN-O to form alloy acceptor attributing to the similar chemical structures. The addition of SN-O as the third component into the D18:Y6 system showed a significant reduction in the nonradiative energy loss and a favorable blend film morphology, thus improves exciton dissociation, charge transport and collection. Consequently, a high PCE of 18.3% was achieved for D18:Y6:SN-O ternary system with simultaneously enhancement of V oc , J sc and FF, which is much higher than that of the binary devices. [ABSTRACT FROM AUTHOR]

We report an electrophilic cyclization of alkynyl imines to afford polysubstituted 3-haloquinolines using CuX-activated N-halosuccinimdes (NXS) as electrophiles. Control experiments demonstrated that the NXS/CuX system might be more active than single NXS and could be applied in the electrophilic cyclization of electron-deficient substrates. [ABSTRACT FROM AUTHOR]

The protocol represents the first example for coumarin synthesis from alkynoates through decarboxylative radical 5-exo annulation and ester migration. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Aminophenols as Efficient Ligand for Copper-Catalyzed Ullmann-Type Synthesis of Diaryl Ethers" by C. Qian and others, published in the periodical "Bulletin of the Korean Chemical Society" in 2013.