Iron Coordination to Hollow Microporous Metal-Free Disalphen Networks: Heterogeneous Iron Catalysts for CO2 Fixation to Cyclic Carbonates

This work shows that a hollow and microporous metal-free N,N′-phenylenebis(salicylideneimine) (salphen) network (H-MSN) can be engineered by Sonogashira coupling of [tetraiodo{di(Zn-salphen)}] building blocks with 1,4-diethynylbenzene in the presence of silica templates and by successive Zn and silica etching. Iron(III) ions could be incorporated into the H-MSN to form hollow and microporous Fe–disalphen networks (H-MFeSN) with enhanced microporosity and surface area. The H-MFeSN showed efficient catalytic performance and recyclability in the CO₂ conversion to cyclic carbonates.     

Gold Nanorod‐Assembled PEGylated Graphene‐Oxide Nanocomposites for Photothermal Cancer Therapy

Gold nanorod‐attached PEGylated graphene‐oxide (AuNR‐PEG‐GO) nanocomposites were tested for a photothermal platform both in vitro and in vivo. Cytotoxicity of AuNR was reduced after encapsulation with PEG‐GO along with the removal of cetyltrimethylammonium bromide (CTAB) from AuNR by HCl treatment. Cellular internalization of the CTAB‐eliminated AuNR‐PEG‐GO nanocomposites was examined using dark‐field microscopy (DFM), confocal Raman microscopy and transmission electron microscopy (TEM). To determine the photothermal effect of the AuNR‐PEG‐GO nanocomposites, A431 epidermoid carcinoma cells were irradiated with Xe‐lamp light (60 W cm^?2) for 5 min after treatment with the AuNR‐PEG‐GO nanocomposites for 24 h. Cell viability significantly decreased by ~40% when the AuNR‐PEG‐GO‐encapsulated nanocomposites were irradiated with light as compared with the cells treated with only the AuNR‐PEG‐GO nanocomposites without any illumination. In vivo tumor experiments also indicated that HCl‐treated AuNR‐PEG‐GO nanocomposites might efficiently reduce tumor volumes via photothermal processes. Our graphene and AuNR nanocomposites will be useful for an effective photothermal therapy.     

Molecular captain: A light‐sensitive linker molecule in poly(ethylene glycol)‐poly(L‐alanine)‐poly(ethylene glycol) triblock copolymer directs molecular nano‐assembly,conformation, and sol‐gel transition

We report a poly(ethylene glycol)‐poly(L ‐alanine)‐azobenzene‐poly(L ‐alanine)‐poly(ethylene glycol) (PEG‐PA‐Z‐PA‐PEG) as a temperature and light sensitive polymer. The poly(ethylene glycol)‐poly(L ‐alanine) diblock copolymers with a flexible‐rigid block structure were coupled by an azobenzene group that undergoes a reversible configurational change between “trans” and “cis” upon exposure to UV and vis light. The single azobenzene molecule embedded in the middle of a block copolymer with a flexible (shell)‐rigid (core) structure significantly affected molecular assembly, micelle size, polypeptide secondary structure, and sol‐to‐gel transition temperature of the polymer aqueous solution, depending on its exposure to UV or vis light. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Tellurium Tetrachloride as an Efficient Chlorinating Agent for Di- or Trialkyl Phosphites: Novel Synthesis of Dialkyl Chlorophosphates

Various dialkyl chlorophosphates are prepared by the reaction of TeCI₄ with di-or trialkyl phosphites in good yields.     

Reaction of Cyclic Sulfates with Phosphines

In their reactions with phosphines, cyclic sulfates 9, 10, 11, and 12 afforded corresponding olefins by way of phosphonium sulfate salts whereas sugar cyclic sulfates 21 and 22 gave anhydrosugar 23.     

Fluorinated Aromatic Diluent for High‐Performance Lithium Metal Batteries

In lithium metal batteries, electrolytes containing a high concentration of salts have demonstrated promising cyclability, but their practicality with respect to the cost of materials is yet to be proved. Here we report a fluorinated aromatic compound, namely 1,2‐difluorobenzene, for use as a diluent solvent in the electrolyte to realize the “high‐concentration effect”. The low energy level of the lowest unoccupied molecular orbital (LUMO), weak binding affinity for lithium ions, and high fluorine‐donating power of 1,2‐difluorobenzene jointly give rise to the high‐concentration effect at a bulk salt concentration near 2 m , while modifying the composition of the solid‐electrolyte‐interphase (SEI) layer to be rich in lithium fluoride (LiF). The employment of triple salts to prevent corrosion of the aluminum current collector further improves cycling performance. This study offers a design principle for achieving a local high‐concentration effect with reasonably low bulk concentrations of salts.     

Nanoformulated Single‐Stranded RNA‐Based Adjuvant with a Coordinative Amphiphile as an Effective Stabilizer: Inducing Humoral Immune Response by Activation of Antigen‐Presenting Cells

As agonists of TLR7/8, single‐stranded RNAs (ssRNAs) are safe and promising adjuvants that do not cause off‐target effects or innate immune overactivation. However, low stability prevents them from mounting sufficient immune responses. This study evaluates the adjuvant effects of ssRNA derived from the cricket paralysis virus intergenic region internal ribosome entry site, formulated as nanoparticles with a coordinative amphiphile, containing a zinc/dipicolylamine complex moiety as a coordinative phosphate binder, as a stabilizer for RNA‐based adjuvants. The nanoformulated ssRNA adjuvant was resistant to enzymatic degradation in vitro and in vivo, and that with a coordinative amphiphile bearing an oleyl group ( CA‐O ) was approximately 100 nm, promoted effective recognition, and improved activation of antigen‐presenting cells, leading to better induction of neutralizing antibodies following single immunization. Hence, CA‐O may increase the efficacy of ssRNA‐based adjuvants, proving useful to meet the urgent need for vaccines during pathogen outbreaks.