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We have discovered that squaraine NCSQ easily react with ketones in the presence of ammonium acetate to form a novel type of squaraine CCSQ It is interesting to find that NCSQs exhibit unusual solid-state fluorescence, whereas CCSQs only exhibit fluorescence in solution. The quantum yield of solid NCSQ-g is measured to be 0.36, which is the highest among solid squaraines found so far. The large spectral overlap between the emission of NCSQs and the absorption of CCSQs, and the structural similarity of these molecules make them excellent energy-transfer (ET) pairs, as exemplified by the ET pair of CCSQ-1/NCSQ-g. When a very small amount (0.05 mol%) of CCSQ-g is doped into NCSQ-g, the ET efficiency reaches up to 96%. The Stern-Volmer quenching constant Ksv is calculated to be 65 800, indicating that CCSQ-1/NCSQ-g forms an extremely efficient ET pair. This study provides a novel skeleton and a facile route to efficient ET pairs. [ABSTRACT FROM AUTHOR]

The encouraging results of preliminary toxicological studies on imidazolium-based ionic liquids provide good opportunities for the development of ionic liquids in biomedical applications. In this work, the polymerized ionic liquid poly[3-butyl-1-vinylimidazolium L-proline salt] has been synthesized as a gene vector. The interaction of poly[3-butyl-1-vinylimidazolium L-proline salt] with DNA was studied by agarose gel electrophoresis. The cell viability was determined through PI (propidium iodine) staining and flow cytometry, showing marginal toxicity toward the cells examined. The transfection efficiency was evaluated through the in vitro transfection experiment. The results indicated that the imidazolium cation had a high binding ability to DNA, and the condensed DNA in the complexes could be effectively protected against enzymatic degradation. Poly[3-butyl-1-vinylimidazolium L-proline salt] could further transfer the reporter gene into the HeLa cell and successfully mediate the gene expression without the aid of additional agent. [ABSTRACT FROM AUTHOR]

Here we disclose a Rh(III)-catalyzed chelation-assisted C(sp³)-H activation of 8-methylquinolines, which can enable intermolecular amidation using commercially available, reliable amides as the amidating reagent to provide an efficient route to quinolin-8-ylmethanamine derivatives. This amidation proceeds at room temperature in moderate to excellent yields, and features good functional group tolerance and complete mono-selectivity. [ABSTRACT FROM AUTHOR]

Hyperbranched polyglycerols 1 and 2 have been synthesized from pentaerythritol and glycidol in a one-pot process by anion ring-opening polymerization. These polymers are modified easily to sulfate or carboxylate-based polyglycerols 3–5 with the SO3–Py complex and sodium chloroacetate, respectively. Polyglycerols 3–5 have been used for the first time as additives for biomimetic crystallization of calcium carbonate. The morphologies of calcite crystals can be controlled by adjusting the functionality, the molecular weight and the secondary structure of the polymer as well as the Ca2+ concentration. Polyglyerol carboxylate 3-Na is capable of mediating the formation of uniform polycrystalline spherules with stacked multilayers. Interestingly, a successive rod–dumbbell–sphere transition can be observed directly, providing considerable insight into the mechanism of formation of calcite microspheres in the presence of 3-Na. Sulfate-based polyglycerols 5-H, 5-Na and 5-Im with different cations (e.g., H+, Na+, imidazolium, respectively) give rise to the mesocrystals with morphologies from truncated rhombohedra to rounded Chinese lantern-like particles to spherules, respectively. In this study, a structural transition from single crystal to mesocrystal to polycrystal has been carried out. [ABSTRACT FROM AUTHOR]

A new catalyst system for the synthesis of α-aryl-substituted nitriles is reported. The bicyclic triaminophosphine P(i-BuNCH[sub 2]CH[sub 2])[sub 3]N (1b) serves as an efficient and versatile ligand for the palladium-catalyzed direct α-arylation of nitriles with aryl bromides. Using ligand 1b, ethyl cyanoacetate and primary as well as secondary nitriles are efficiently coupled with a wide variety of aryl bromides possessing electron-rich, electron-poor, electron-neutral, and sterically hindered groups. [ABSTRACT FROM AUTHOR]

The cyanomethyl radical was easily generated from acetonitrile by using DTBP, which was applied to a cascade alkene addition and cyclization reaction to construct useful oxindole derivatives. This protocol features simple manipulation, cheap reagents and a broad substrate scope. In addition, nitro substituted oxindoles were also synthesized for the first time. [ABSTRACT FROM AUTHOR]

The room-temperature oxidative C-H/C-H cross-couplings between (hetero)arenes and alkenes, coumarins or quinones have been reported by using a highly electrophilic palladium species [Pd(TFA)2], generated in situ from Pd(OAc)2 and TFA, as the catalyst and cheap (NH4)2S2O8 as the oxidant under air. [ABSTRACT FROM AUTHOR]

The Cu-catalysed oxidative C--H/C--H coupling reaction of azoles has been used for the first time to develop polymerisation, which provides an efficient method for the preparation of polybenzodiimidazoles. These polymers exhibit high molecular weights, regioregularity, blue-emitting performance and thermal stability. [ABSTRACT FROM AUTHOR]

A novel class of helical nonracemic tubular coordination polymers, which can immobilize a wide range of solvents at very low concentrations, have been synthesized for the first time in the absence of chiral influences and appended groups. [ABSTRACT FROM AUTHOR]

Novel supported task-specific ionic liquids have been developed for the first time via the ionic-pair coupling of imidazolium cation of the modified polystyrene support with L-proline. The materials have shown an efficient metal scavenging ability (e.g., Cul, Pd(OAc)2, Pd°, and lrCl3) without the aid of a nonimmobilized ionic liquid, which relies on the highly synergistic effect of the coordination with the nitrogen atom and the COO- group of the L-proline moiety, electrostatic forces, and steric protection. The resulting metal-soaked supported ionic liquids can be used as efficient heterogeneous catalysts. These materials have been investigated in the Cul-catalyzed N-arylation of nitrogen-containing heterocycles and exhibit much higher catalytic activity and a more extensive structural range of aryl and heteroaryl halides than those exhibited by free L-proline in combination with Cul both in the ionic liquid ([BMIM][BF4]) and in the corresponding homogeneous reaction conditions. The Cul-soaked catalyst 4a-2 can be recycled for nine runs at least without any considerable loss of activity. To the best of our knowledge, our catalytic process is among the most efficient approaches to the N-arylation of imidazoles with aryl halides so far reported. Furthermore, the Pd-soaked material 4a-2 also shows higher catalytic activity in the solvent-free hydrogenation of styrene to ethylbenzene. This new concept is generally applicable and may easily be extended to other supported task-specific ionic liquids. [ABSTRACT FROM AUTHOR]

The article synthesizes on the switching the polymer microparticles through ultrasound and its possible reaction to nanofibers. According to the article, this switching can be considered as another breakthrough, where hybrid inorganic and organic materials can be formulated through interaction extension of metal ligand coordintation. Furthermore, there are several studies have conducted regarding the effectiveness of supramolecular gels for the said switching.

The title compound, C29H33N5, is a new chiral bis(imidazolyl)pyridine derivative with a skeleton similar to the bis­(oxazol­yl)pyridine derivatives, which have been extensively used as ligands in various asymmetric catalytic reactions. The most prominent feature of the present compound is the considerable sp2 character of N atoms of the imidazoline rings. The substituents at the N sp2 atoms can provide a means for tuning the electronic and conformational properties of the compound. [ABSTRACT FROM AUTHOR]