Molecular Triplet Generation Enabled by Adjacent Metal Nanoparticles.

High-efficiency generation of spin-triplet states in organic molecules is of great interest in diverse areas such as photocatalysis, photodynamic therapy, and upconversion photonics. Recent studies have introduced colloidal semiconductor nanocrystals as a new class of photosensitizers that can efficiently transfer their photoexcitation energy to molecular triplets. Here, we demonstrate that metallic Ag nanoparticles can also assist in the generation of molecular triplets in polycyclic aromatic hydrocarbons (PAHs), but not through a conventional sensitization mechanism. Instead, the triplet formation is mediated by charge-separated states resulting from hole transfer from photoexcited PAHs (anthracene and pyrene) to Ag nanoparticles, which is established through the rapid formation and subsequent decay of molecular anions revealed in our transient absorption measurements. The dominance of hole transfer over electron transfer, while both are energetically allowed, could be attributed to a Marcus inverted region of charge transfer. Owing to the rapid charge separation and the rapid spin-flip in metals, the triplet formation yields are remarkably high, as confirmed by their engagement in production of singlet oxygen with a quantum efficiency reaching 58.5%. This study not only uncovers the fundamental interaction mechanisms between metallic nanoparticles and organic molecules in both charge and spin degrees of freedom but also greatly expands the scope of triplet "sensitization" using inorganic nanomaterials for a variety of emerging applications.

Atom- and step-economic 1,3-thiosulfonylation of activated allenes with thiosulfonates to access vinyl sulfones/sulfides.

A new type of organocatalyzed 1,3-thiosulfonylation has been developed to straightforwardly access highly functionalized vinyl sulfones, which features mild conditions, atom- and step-economy, practicability, conciseness, and environmental friendliness. Moreover, these valuable products can be transformed to vinyl sulfides via a base-promoted isomerization. The versatile route can efficiently and rapidly introduce SCD3 groups with excellent levels of deuterium content (>99% D) by utilizing our newly developed SCD3 reagents. Gram-scale operations and further transformations are smoothly carried out, providing promising applications for drug discovery.

Correction: Enantioselective synthesis of functionalized 1,4-dihydropyrazolo-[4',3':5,6]pyrano[2,3-b]quinolines through ferrocenyl-phosphine-catalyzed annulation of modified MBH carbonates and pyrazolones.

Correction for 'Enantioselective synthesis of functionalized 1,4-dihydropyrazolo-[4',3':5,6]pyrano[2,3-b]quinolines through ferrocenyl-phosphine-catalyzed annulation of modified MBH carbonates and pyrazolones' by Xiao Xiao et al., Chem. Commun., 2021, DOI: .

Enantioselective synthesis of functionalized 1,4-dihydropyrazolo-[4',3':5,6]pyrano[2,3-b]quinolines through ferrocenyl-phosphine-catalyzed annulation of modified MBH carbonates and pyrazolones.

An enantioselective synthesis of highly functionalized 1,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-b]quinolines from modified MBH carbonates and pyrazolones via a chiral phosphine-mediated alkylation/annulation sequence has been realized. The chiral dihydropyrano[2,3-c]pyrazoles bearing bio-active condensed heterocycles were facilely formed in good chemical yields and with high to excellent enantioselectivity by utilizing low catalyst loading.

Synthesis of Au-Fe3O4 heterostructured nanoparticles for in vivo computed tomography and magnetic resonance dual model imaging.

Water-soluble Au-Fe3O4 heterostructured nanoparticles with high biocompatibility were synthesized and applied as a dual modality contrast agent. These nanoparticles present strong CT/MRI contrast enhancement in a rabbit model. Low concentrations of Au-Fe3O4 were found to obtain a similar effect to high concentrations of a commercial iodine agent in the CT image.

Synthesis of Pt@Fe2O3 nanorods as MRI probes for in vivo application.

Magnetic Fe(2)O(3) nanorods with low cell toxicity were successfully synthesized via a wet-chemical method. In vivo studies with a rabbit model show that the nanorods exhibit excellent T(2) signal enhancement. This work demonstrates that magnetic nanorods may provide a new type of MR enhancement agent for use in biomedical applications.