Sherrillhess2612

A dearomative allylation of naphthyl cyanohydrins with allyl borates and allyl stannanes under palladium catalysis was developed. At the initial stage of this study, the dearomative reaction (C4 substitution of the aromatics) was competing with benzyl substitution. To circumvent this issue, the use of palladium and meta-disubstituted triarylphosphine as the catalyst in a 11 ratio was found to enhance the site selectivity, furnishing the desired dearomatized products. Further derivatizations of products were also successful.Recently, aggregation-induced emission (AIE) has attracted extensive attention. Herein we report an AIP-active "turn-off" nanosensor based on ferric-specific quenching of photoluminescence (PL) of water-soluble Au(I)-cysteine nanocomplexes. The Au(I)-cysteine nanocomplexes were AIP-active, showing a PL peak at 590 nm. Transmission electron microscopy (TEM) characterization revealed that they show the characteristic morphology of nanofibers. High-speed centrifugation characterization and zeta potential measurement indicated that they are highly water-soluble. Interestingly, their PL could be quenched specifically by ferric ions over the other common 18 metal ions. Further TEM characterizations revealed that the quenching process was accompanied by the ferric-specific dissociation of Au(I)-cysteine nanofibers. These observations have enabled the development of a water-soluble AIP-active "turn-off" nanosensor based on Au(I) nanocomplexes for selective and sensitive detection of ferric ions. This study indicates that specific quenching and disassociation of AIP-active nanocomplexes might be a promising route for development of novel luminescent nanosensors.An effectual and understandable route for the fabrication techniques of stereoscopic NO2 sensor is provided in this work. As the gas-sensing layer of the sensor, copper phthalocyanine (CuPc) grew on the top of poly(vinyl alcohol) (PVA) nanofibers (NFs). The sensitivity of the CuPc/PVA NFs stereoscopic sensors to NO2 was over 829%/ppm, while the sensitivity of the continuous CuPc films sensors was 2 orders of magnitude lower than that of the stereoscopic ones. To the responsivities at 25 ppm of NO2, the CuPc/PVA NFs stereoscopic sensors were about four times stronger than that of the continuous CuPc films sensors. For the recovery time, the CuPc/PVA NFs stereoscopic sensors were over eight times faster than the continuous CuPc films sensors. This general tactic can be used to prepare various toxic gas sensors to improve the overall performance of the devices.Ultralong organic phosphorescence strongly depends on the formation of aggregation, while it is difficult to obtain in dilute environments on account of excessive internal and external molecular motions. Herein, ultralong single molecule phosphorescence (USMP) at room temperature was achieved in the monomer state by coassembling biphenyl and naphthalene derivatives at low density with polyvinyl alcohol (PVA), where PVA provides a confined environment to stabilize the triplet state. Various factors that affect the USMP were studied, including aggregation, conformation, temperature and moisture. In these systems, the formation of aggregates through intermolecular stacking and hydrogen bonding interactions in the film or crystal phases completely suppresses the USMP. However, the fluorescence is enhanced when coassembling these compounds at high concentration with PVA, and becomes stronger in their powder state, indicating that the intersystem crossing process is blocked by the aggregation. Theoretical calculations suggest that the aggregation depresses spin-orbit coupling between the excited singlet and triplet states and enhances nonradiative quenching process. Moreover, relatively twisted conformation is more conducive to the occurrence of intersystem crossing than planar conformation. The USMP shows delicate and reversible sensitivity to the changes of temperature and moisture, rendering them with the applicability as smart organic optoelectronic materials.The application of stabilized iodonium ions in organic synthesis remains largely unexplored. Herein, a metal-free domino synthesis of Z-selective α,β-diphenylthio enones is developed from easily available benzylic secondary alcohols employing thiophenol-stabilized iodonium ion as a catalyst. This methodology was further extended to five-membered and six-membered cyclic secondary alcohols. The UV-vis experiments suggest the formation of thiol-coordinated iodine(I) intermediates. Several control experiments establish that the reaction proceeds via the oxidation of alcohol to ketone, α-thiolation of ketones followed by α,β-unsaturation, and finally the β-thiolation of α,β-unsaturated ketones to generate bis-vinyl sulfides. The in situ-generated stabilized iodonium ion is highly efficient to catalyze multiple functional group transformations in a domino manner.Lipid droplets (LDs) are closely connected to many physiological processes and abnormal LDs are related to many diseases. Herein, a family of two-photon fluorescence compounds based on the aurone skeleton were developed as efficient LDs imaging probes. They exhibit the obvious solvatochromism effect from blue to orange emission (∼140 nm shift) in various solvents. The robust probes possess low toxicity to living cells, high photobleaching resistance, and superior photostability and can light up LDs with high specificity. Furthermore, the probe DMMB (aurone skeleton with dimethylamino) was carefully applied in real-time monitoring of the morphological changes of LDs and the interactions between LDs and mitochondria under specific physiological conditions (e.g., starvation). Selleck Screening Library We have observed for the first time the dynamic change between mitochondria and LDs when mitochondrial damage is caused by a large excess of H2O2 in a short period of time.In electrochemistry, the carbazole is generally coupled to dimer but not to polymer. This work has reported that organic electropolymerization (OEP) of 4,4',4″-tri(N-carbazolyl)triphenylamine (TCTA) would form a high cross-linked carbazole polymer by its high activity/reversibility and a synchronous viscosity control. It has significantly improved the OEP film quality of both hole-transporting and electroluminescent layers in organic light-emitting diodes. As a result, the conductivity and power efficiency of the organic light-emitting diodes with TCTA are eight and four times of that without TCTA. A prototype display device with a 1.7 in. monochrome passive matrix of 58 ppi under the driving chip is successfully fabricated with accurate pixel size and uniform electroluminescence, which shows a great potential of OEP in the electroluminescent application.