Triacetic acid lactone as a bioprivileged molecule in organic synthesis

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Carbon monoxide as a selective reducing agent in organic chemistry

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High ability of a blue phase polymer based on a diacetylene alcohol derivative

The effect of prolonged UV irradiation and high temperature on a blue phase polymer film prepared by the Langmuir–Schaefer method based on 11-hydroxyundeca-6,8-diyn-1-yl N-(4-methoxyphenyl)carbamate was evaluated. The high stability of the polymer under extreme external influences was revealed. The transition of a monolayer to a bilayer with increasing surface pressure during the Langmuir layer formation was confirmed by atomic force microscopy.     

Push-pull molecules bearing a hydrazonocyclopentadiene acceptor moiety: from the synthesis to organic photovoltaic applications

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Pyridinium bromide as a new mediator for electrochemical transformations involving CH-acids

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Causes of the double maximum conductivity of nanocomposite polymer electrolytes for lithium power sources

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A linear supramolecular polymer based on host-guest recognition and metal-ligand coordination

A linear main-chain supramolecular polymer was constructed in aqueous solution via γ-CD host recognition with coumarin unit as well as metalligand coordination between terpyridine unit and Zn²⁺. Besides, the self-assembly behavior and morphological property of this supramolecular polymer system were characterized by DLS and TEM experiments.     

Recent advances in organic pressure-responsive luminescent materials

Organic luminescent materials are very sensitive to external stimuli,such as pressure,temperature,and electric field.The luminescent properties of some organic luminescent materials significantly change under high pressure.Some materials may show luminescence discoloration,whereas some may exhibit luminescence enhancement.These properties have many potential applications in anticounterfeiting,force sensor,data recording and storage,and luminescent devices,thereby greatly attracting the attention of scientists.In this review,the progress of research on these materials at high pressure in recent years is summarized.     

Inverse electron demand Diels–Alder reaction as a novel method for functionalization of natural chlorins

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Metal-organic frameworks as materials for applications in sensors

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1,1′-Carbonyldiimidazole as a cyclodehydrating agent for the Castagnoli–Cushman reaction of dicarboxylic acids and imines

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Acid-base isomerization of hybrid molecules based on fullerene C60 and spiropyrans

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Chiral copper-catalyzed enantioselective Michael difluoromethylation of arylidene meldrum's acids with (difluoromethyl)zinc reagents

The catalytic enantioselective difluoromethylation of arylidene Meldrum's acids with (difluoromethyl)zinc reagent, easily prepared through zinc/iodide exchange reaction of difluoroiodomethane and diethylzinc with co-solvent such as pyridines, by a chiral phosphoramidite-Cu catalyst is shown to provide highly enantioselective sp [3]-difluoromethyl Michael addition product in good yields and high levels of enantioselectivity.     

Recyclization of glaucine as a new route to litebamine derivatives

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Water at surfaces and interfaces: From molecules to ice and bulk liquid

The structure and growth of water films on surfaces is reviewed, starting from single molecules to two-dimensional wetting layers, and liquid interfaces. This progression follows the increase in temperature and vapor pressure from a few degrees Kelvin in ultra-high vacuum, where Scanning Tunneling and Atomic Force Microscopies (STM and AFM) provide crystallographic information at the molecular level, to ambient conditions where surface sensitive spectroscopic techniques provide electronic structure information. We show how single molecules bind to metal and non-metal surfaces, their diffusion and aggregation. We examine how water molecules can be manipulated by the STM tip via excitation of vibrational and electronic modes, which trigger molecular diffusion and dissociation. We review also the adsorption and structure of water on non-metal substrates including mica, alkali halides, and others under ambient humid conditions. We finally discuss recent progress in the exploration of the molecular level structure of solid-liquid interfaces, which impact our fundamental understanding of corrosion and electrochemical processes.     

Chiral terpene auxiliaries IV: new monoterpene PHOX ligands and their application in the catalytic asymmetric transfer hydrogenation of ketones

New PHOX ligands, derived in three steps from (1R,2S,3R,5R)-3-amino-apopinan-2-ol 1 and (1R,2R,3S,5R)-3-amino-pinan-2-ol 2 were applied as chiral ligands for the formation of ruthenium catalysts. The catalysts were used in asymmetric transfer hydrogenations of prochiral ketones producing the corresponding alcohols in moderate to high yields and enantioselectivity.     

Chiral ethylene-bridged flavinium salts: the stereoselectivity of flavin-10a-hydroperoxide formation and the effect of substitution on the photochemical properties

A series of chiral non-racemic N¹,N¹⁰-ethylene bridged flavinium salts 4 was prepared using enantiomerically pure 2-substituted 2-aminoethanols (R?=?isopropyl, phenyl, benzyl, 4-methoxybenzyl, 4-benzyloxybenzyl) derived from amino acids as the sole source of chirality. The flavinium salts were shown to form 10a-hydroperoxy- and 10a-methoxy-adducts with moderate to high diastereoselectivity depending on the ethylene bridge substituent originating from the starting amino acid. High diastereoselectivities (dr values from 80:20 to >95:5) were observed for flavinium salts bearing benzyl substituents attached to the ethylene bridge. The benzyl group preferred the face-to-face (syn) orientation relative to the flavinium unit; thereby effectively preventing nucleophilic attack from one side. This conformation was found to be the most stable according to the DFT calculations. Consequently, the presence of benzyl groups causes intermolecular fluorescence quenching resulting in a significant decrease in the fluorescence quantum yield from 11% for 4a bearing an isopropyl substituent to 0.3% for 4c containing a benzyl group and to a value lower than 0.1% for the benzyloxybenzyl derivative 4e.     

Sulfated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

The utility of a series of sulfated cyclodextrins as water-soluble chiral NMR solvating agents for cationic substrates is described. Sulfated α-, β- and γ-cyclodextrin with degrees of substitution of 12, 13 and 14, respectively, a sulfated β-cyclodextrin with a degree of substitution of 9 and a sulfobutyl ether β-cyclodextrin with a degree of substitution of 6.3 are examined. Results with 33 water-soluble cationic organic salts are reported. Chiral differentiation with the sulfated cyclodextrins is compared to prior results obtained with anionic carboxymethylated and phosphated cyclodextrins. The highly sulfated cyclodextrins are often more effective at causing enantiomeric differentiation in ¹H NMR spectra than the sulfobutyl ether, carboxymethylated and phosphated cyclodextrins, and are recommended as the first choice of a chiral solvating agent for the analysis of chiral cationic organic salts in aqueous solution.