Near-Infrared-Light-Induced Iron(I) Dimer-Enabled Radical Cascade Reactions of Fluoroalkyl Bromides for the Synthesis of Ring-Fused Quinazolinones.

The use of an earth-abundant and inexpensive iron complex as a catalyst, coupled with near-infrared (NIR) light as the energy source, for radical reactions with alkyl halides has been far less developed. In this study, we report NIR light-mediated iron(I) dimer-catalyzed radical cascade reactions of fluoroalkyl bromides for the synthesis of ring-fused quinazolinones bearing a difluoromethyl group. In this process, the 3-bromo-1,10-phenanthroline ligand facilitates the reactivity of [CpFe(CO)], thereby improving the efficiency of the reaction.

Additive-Free, Visible-Light-Enabled Decarboxylative Alkylation of Enamides.

Enamides are versatile precursors for synthesizing bioactive compounds. As their alkylations often require perstoichiometric amounts of oxidants, transition metals, or photocatalysts, we herein report a simple alternative for their alkylations by just using visible light to irradiate the mixture of the readily available -hydroxyphthalimide esters and enamides without an additive. The reaction involves the photoactivation of a π-π stacking EDA complex between the substrates.

Visible-Light-Induced Selective Photolysis of Phosphonium Iodide Salts for Monofluoromethylations.

The sigma (σ)-hole effect has emerged as a promising tool to construct novel architectures endowed with new properties. A simple yet effective strategy for the generation of monofluoromethyl radicals is a continuing challenge within the synthetic community. Fluoromethylphosphonium salts are easily available, air- and thermally stable, as well as simple-to-handle.

Correction to "Gold Nanorods Embedded in Polymeric Film for Killing Bacteria by Generating Reactive Oxygen Species with Light".

[This corrects the article DOI: 10.1021/acsabm.9b00343.

Visible-Light-Triggered Iodinations Facilitated by Weak Electrostatic Interaction of N-Heterocyclic Carbenes.

N-heterocyclic carbenes (NHCs) are well-known as ligands and organocatalysts, but there is no recognition for their catalytic role as a stabilizer through electrostatic interaction rather than electron donation. By utilizing the electrostatic interaction, we herein describe the success of a visible-light-triggered radical-radical cross-coupling of N-alkenoxypyridinium salts and NaI, giving a variety of α-iodo ketones. Computational studies characterize the stabilization role of NHCs.

Gold Nanorods Embedded in Polymeric Film for Killing Bacteria by Generating Reactive Oxygen Species with Light.

For the first time, anisotropic gold nanorods (AuNRs) were embedded with a photosensitizer dye (crystal violet) in polyurethane (PU) matrix to create the effective antimicrobial film, capable of killing Gram-negative bacteria on its surface when exposed to white light. The dye, when activated with white light, interacts with the AuNRs to generate reactive oxygen species (ROS), which kill bacteria. With a proper control of the aspect ratio (2.

A centrifugation-assisted visual detection of SNP in circulating tumor DNA using gold nanoparticles coupled with isothermal amplification.

Detection of single-nucleotide polymorphism (SNP) in circulating tumor DNA (ctDNA) is challenging because of the large DNA fragmentation (∼150 nt) and the strong background of normal cell free DNA (cfDNA). Here we developed a rapid centrifugation-assisted colorimetric assay using gold nanoparticles (AuNPs) coupled with isothermal amplification to detect a SNP (G to C mutation) in KRAS, p.G13D in ctDNA.

Formulation of DNA chimera templates: Effects on emission behavior of silver nanoclusters and sensing.

Single strand DNA (ssDNA) chimeras consisting of a silver nanoclusters-nucleating sequence (NC) and an aptamer are widely employed to synthesize functional silver nanoclusters (AgNCs) for sensing purpose. Despite its simplicity, this chimeric-templated AgNCs often leads to undesirable turn-off effect, which may suffer from false positive signals caused by interference. In our effort to elucidate how the relative position of NC and aptamer affects the fluorescence behavior and sensing performance, we systematically formulated these NC and aptamer regions at different position in a DNA chimera.

UV-vis spectroscopy and dynamic light scattering study of gold nanorods aggregation.

Gold nanorods (AuNRs) were used as spectroscopic sensing elements to detect specific DNA sequences with a single-base mismatch sensitivity. The assay was based on the observation that the stabilizing repulsive forces between CTA(+)-coated AuNRs can be removed by citrate ions, which causes aggregation among AuNRs; whereas nucleic acids of different structures[ i.e.

Electrochemical impedance sensing of DNA hybridization on conducting polymer film-modified diamond.

The impedimetric sensing of DNA hybridization on polyaniline/polyacrylate (PANI/PAA)-modified boron-doped diamond (BDD) electrode has been investigated. An ultrathin film of PANI-PAA copolymer was electropolymerized onto the diamond surfaces to provide carboxylic groups for tethering to DNA sensing probes. The electrochemical impedance and the intrinsic electroactivity of the polymer-diamond interface were analyzed after the hybridization reaction with target and non-target DNA.