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Metal-organic frameworks (MOFs) are promising sacrificial templates for synthesis of carbon functional materials with a relatively high concentration of stabilized metallic species. In this work coordination polymers based on trans,trans-muconic acid and transition metals (Cu, Zn, Ni, Co) were prepared and selected as the precursors for supramolecular organization of nanocomposites. The coordination polymers and metal-containing thermolysis products obtained were characterized using a number of analytical techniques including powder X-ray diffraction, elemental analysis, thermal gravimetric analysis, scanning electron microscopy and volumetric nitrogen adsorption/desorption. This study extends the application of coordination polymers as precursors for designing of carbon materials incorporating metal nanoparticles. It is shown that appropriate choice of metal-organic precursors in solid-phase thermolysis allowed to get materials with determined morphologies.

We studied HCl uptake by MgCl2 and sea salt over a relative humidity (RH) range from 0% to 34% at 278-313 K using a differential bead-filled flow tube coupled to a high-pressure chemical ionization mass spectrometer. The results showed that dry MgCl2 and sea salt are essentially inert to gaseous HCl with a probability of less than 10-6 . However, under humid conditions, HCl was found to be efficiently taken up by wet inorganic surfaces. The HCl uptake coefficient for MgCl2 and sea salt increased squarely with RH, reaching a value of 0.00123 and 0.00171, respectively, at 29% RH and 298 K. Such wetting behavior is even enhanced at elevated temperatures, with the coefficient reaching 0.00208 and 0.00239, respectively, at 313 K. Based on the study of the dependence of γHCl on the initial HCl concentration, we estimate γHCl as 0.012 at 24% RH at a typical HCl concentration in the troposphere. In addition, the observation of the remarkable enhancement in the OH uptake by the HCl-treated salts agrees with the results of our previous investigation, which suggested that water absorption on salts enhances γOH by lowering the surface pH. The proposed mechanism of HCl uptake by sea salt aerosol has implications for ozone production in the marine boundary layer.

The addition of Lewis acids change the reaction mechanism of the cycloaddition of N-vinylpyrroles with azomethine imine and C,N-diarylnitrones. The formal (3+3)-cycloaddition is observed instead of (3+2)-dipolar cycloaddition, which take place in the absence of catalysts. This unusual (3+3)-cycloaddition leads to heterocyclic compounds with pyrazolo[1,2-a]pyrrolo[1,2-d][1,2,4]triazine- and pyrrolo[2,1-d][1,2,5]oxadiazine cores, which are difficultly achievable by other methods.

Original multiscale flaked silver SERS-substrate (MFSS substrate) was applied for glycated albumin (GA) biosensing. The substrate is composed from silver flakes that have three orders of magnitude size dispersion: from 50 nm to 2 μm. The multiscale silver structure refracts the incident light and various surface plasmons are excited. Some of the internal plasmons are localized and give rise of the large local electric field. It was demonstrated that Raman scattering signal strongly depends: a) on “hot spots” formation at the edges and points of contact of silver plates, and b) on the angle of incidence. As a result the silver structure operates as an effective SERS substrate. To achieve the selectivity to glycated part, the surface of SERS-substrate was modified with 4-mercaptophenylboronic acid (4-mPBA). Various saccharides (Fru, Glc, Suc, Dex) were taken as model compounds for the glycated proteins determination. The saccharides contain cis-diol groups that form five- or six-membered ethers with boronic acid. Spectrum of SERS-substrate changes after sugar/glycated albumin treatment. Main differences in the SERS-spectra of sugar/glycated albumin treated SERS-substrate and control are referred to phenylboronic acid vibrations (999, 1021, 1072 and 1589 cm−1). Principal component analysis (PCA) and Partial Least Squares Regression (PLS-R) were used to discriminate spectra and to construct calibration curve, as well as to measure GA values in real samples of human plasma. Multiscale flaked silver SERS-substrate modified with 4-mPBA allows quantitative one-step biosensing of glycated albumin in 15 μl of human plasma.

Hitherto unknown N-allenylpyrrole-2-carbaldehydes were synthesized via the formylation of readily available N-allenylpyrroles under the action of the mild formylating complex DMF/(COCl)2. The reaction selectively proceeds in the case of pyrroles with electron-withdrawing substituents to afford the products in good to excellent yields. For pyrroles bearing electron-donating substituents, the reaction proceeds in a cascade manner to deliver unusual complex products, the structure of which was confirmed by X-ray diffraction analysis. The target N-allenylpyrrole-2-carbaldehydes represent promising synthons for organic synthesis.

Asymmetric meso-CF3-dipyrromethanes with amino- and nitrogen heterocyclic functions, a new family of the BODIPY dye precursors, have been synthesized in 70–90 % yield by condensation of trifluoro(pyrrolyl)ethanols with pyrroles in the presence of AlCl3. This catalyst, for the first time, was shown to be more efficient than commonly used P2O5, which was entirely inactive in the condensation of pyrroles having basic substituents (amino group and pyrazole moiety).

1,3-Dipolar cycloaddition of various nitrile oxides to substituted N-vinylpyrroles proceed with high efficiency and selectivity with the formation of single isomer of 5-pyrrolyl-substituted isoxazoline. The reaction of N-vinylpyrroles with cyclic azomethine imines occurs regioselectively affording 7-(pyrrol-1-yl)- substituted pyrazolo[1,2-a]pyrazolones as a mixture of two diastereomers.

Dibutyl ketone, cyclohexanone, acetophenone, α-tetralone, and methyl 2-thienyl ketone were converted into the corresponding 2,3-substituted pyrroles by reaction with hydroxylamine hydrochloride and 1,2-dibromoethane in the system KOH-DMSO.

1-(1-Methyl-1H-pyrrol-2-yl)prop-2-yn-1-ol has been synthesized for the first time by ethynylation of 1-methyl-1H-pyrrole-2-carbaldehyde with acetylene in the superbasic system KOH-DMSO-H2O under atmospheric pressure.

The reaction of pyrrole-2-carbonitriles with hydrazine hydrate in the presence of hydrazine dihydrochloride (ethylene glycol, 130-132°С, 1-2 h, argon atmosphere) affords the hitherto unknown 3,5-bis(1H-pyrrol-2-yl)-4H-1,2,4-triazol-4-amines in up to 86% yield.

A new family of unnatural, optically active amino acids containing the pyrrole moiety have been synthesized by condensation of 1-vinylpyrrole-2-carbaldehydes with L -lysine under mild conditions (EtOH, room temp., 2.5-3 h, 0.5 wt.-% of CF 3 CO 2 H) in up to 90 % yields. Unlike non-vinylated analogues, 1-vinylpyrrole-2-carbaldehydes react chemo-, regio-and stereospecifically with an e-amino group only to afford products of exclusively (E) configuration. The amino acids synthesized containing aromatic or condensed aromatic substitutents in the pyrrole ring fluoresce in the UV/Vis region (λ max = 350-382 nm, Stokes shifts 6150-7800 cm -1 ).

1-Vinylpyrroles are formylated by the N, N-dimethyl-formamide/oxalylchloride reagent system (CH 2 Cl 2 , r.t., 40min) to give the corresponding 1-vinylpyrrole-2-carbaldehydes inyields up to 97%.

A new highly synthetically potent series of bifunctional pyrroles, 1-vinylpyrrole-2-carbonitriles, were synthesized from readily available 1-vinylpyrrole-2-carbaldehyde oximes by two methods: (1) reaction with acetylene (KOH/DMSO, 70 °C, 10 min, yields 58–67%) and (2) reaction with acetic anhydride (90–100 °C, 5 h, yields 83–93%). Starting from 2-phenyl-1-vinylpyrrole, the one-pot synthesis of the corresponding 1-vinyl-2-carbonitrile was accomplished directly by successive treatment with a DMF/(COCl) 2 complex, NH 2 OH·HCl/NaOAc, and acetic anhydride (yield 58%).

An experimental study of the dependence of the OH uptake coefficient gamma OH over a relative humidity of 0-48% was carried out at 100 Torr and room temperature, using a differential bead-filled flow tube coupled to a high-pressure chemical ionization mass spectrometer. Various organic (paraffin wax, pyrene, glutaric acid, and soot) and inorganic (NaCl, KCl, MgCl2, CaCl2, Na2SO4, and sea salt) surfaces served as proxies for tropospheric aerosols. A virtual cylindrical flow tube approximation and a surface coating dilution technique were successfully employed in the study, which included measurements of high radical uptake with an initial probability of near unity. For inorganic salts, the effect of water vapor, enhancement or inhibition of gamma OH, was found to be dependent on the blocking of anions and changes in surface pH. Although OH uptake by NaCl, the major component of sea-salt aerosols, is weakly dependent on water vapor, it is enhanced by a factor of approximately 2 for MgCl2 and determines the net relative humidity dependence of the radical uptake on sea salt, which is enhanced by a factor of approximately 4. For the organic surfaces studied, the enhancement effect of a factor 4 was also observed only for a hydrophilic organic surface, namely, glutaric acid. Results of the uptake studies suggest that the effect of relative humidity is important and should be accounted for in atmospheric modeling of tropospheric aerosol chemistry.

The diffusion of OH, HO2, and O3 in He, and of OH in air, has been investigated using a coated-wall flow tube reactor coupled to a chemical ionization mass spectrometry. The diffusion coefficients were determined from measurements of the loss of the reactive species to the flow tube wall as a function of pressure. On the basis of the experimental results, D(OH-He) = 662 +/- 33 Torr cm2 s-1, D(OH-air) = 165 +/- 20 Torr cm2 s-1, D(HO2-He) = 430 +/- 30 Torr cm2 s-1, and D(O3-He) = 410 +/- 25 Torr cm2 s-1 at 296 K. We show that the measured values for OH and HO2 are in better agreement with measured values of their polar analogues (H2O and H2O2) compared with measured values of their nonpolar analogues (O and O2). The measured value for OH in air is 25% smaller than that for O (the nonpolar analogue). The difference between the measured value for HO2 and O2 (the nonpolar analogue) in air is expected to be even larger. Also we show that calculations of the diffusion coefficients based on Lennard-Jones potentials are in excellent agreement with the measurements. This gives further confidence that these calculations can be used to estimate accurate diffusion coefficients for conditions where laboratory data currently do not exist.

A series of 2,2'-dipyrrole monomers separated by aza-spacers (N,N'-bis-(1H-pyrrol-2-ylmethylene)-benzene-1,4-diamine; N-4,N-4'-bis(1H-pyrrol-2-ylmethylene)-biphenyl-4,4'-diamine; N,N'-bis-[1-(1H-py ...

New dielectric metamaterial based on the Bragg filter comprising ten dielectric bilayers was investigated. Each bilayer is the thin films of silicone dioxide ( SiO 2 ) and another film of zirconium dioxide ( ZrO 2 ). The surface of the multilayer film is profiled. It has a form of periodic system of rectangles separated by the open gaps. We use the computer simulation as well as analytical solution to find the reflectance of the multilayer as a function of the wavelength and electromagnetic (em) field distribution. The multilayer system reveals the enhancement of em fields at the surface. The considered Bragg filter was modified by Raman-active structure made of gold nanoparticles with chemically attached 3,3-thio-bis(6- nitrobenzoic acid) - (TNB). The high Surface Enhanced Raman Scattering (SERS) signal was detected.

Single isomers of pyrrolyl-substituted isoxazoline (III) are highly efficiently and selectively obtained by 1,3-dipolar cycloaddition of various nitrile oxides (I) to a variety of substituted N-vinylpyrroles.

New dielectric metamaterial based on the Bragg filter comprising ten dielectric bilayers was investigated. Each bilayer is the thin films of silicone dioxide (SiO2) and another film of zirconium dioxide (ZrO2). The surface of the multilayer film is profiled. It has a form of periodic system of rectangles separated by the open gaps. We use the computer simulation as well as analytical solution to find the reflectance of the multilayer as a function of the wavelength and electromagnetic (em) field distribution. The multilayer system reveals the enhancement of em fields at the surface. The considered Bragg filter was modified by Raman-active structure made of gold nanoparticles with chemically attached 3,3'-thio-bis (6-nitrobenzoic acid) — (TNB). The high Surface Enhanced Raman Scattering (SERS) signal was detected.

1-Vinylpyrrole-2-carbaldehydes react with phosphorus pentachloride (benzene, 10–15 °C) to afford E-2-(2-dichloromethylpyrrol-1-yl)vinylphosphonium hexachlorophosphates in up to 85% yield, which after treatment with SO2 (benzene, rt) are converted into E-2-(2-dichloromethylpyrrol-1-yl)vinylphosphonyl dichlorides in 50–75% yields.

Using a flow-tube reactor coupled to a chemical ionization mass spectrometer, we investigated the heterogeneous loss of OH on Halocarbon wax, two types of organized organic monolayers, and several solid organic surfaces (paraffin wax, stearic acid-palmitic acid mixture, pyrene, and soot) that are representative of surfaces found in the troposphere. The heterogeneous reaction is very efficient: the reaction probability is greater than 0.1 for all the organic surfaces investigated, except for Halocarbon wax. These results indicate that OH-organic heterogeneous reactions will significantly modify the hygroscopic properties and cloud condensation nuclei (CCN) ability of organic surfaces in the troposphere, and thus may play an important role in the Earth’s radiative balance by affecting the properties of clouds. We also determined the diffusion coefficient of OH in helium to be 665 ( 35 Torr cm 2 s -1 . This value is close to that of its polar analogue, H 2O, suggesting that the diffusion coefficient of OH can be calculated accurately with H2O transport properties.

The impact of water-soluble and amphiphilic polymers with different structures, namely carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), was studied on the photoactivity of chlorin photosensitizers (PSs) in photodynamic therapy (PDT). It was shown that such polymers can cause a considerable increase in the PS activity, both in the process of singlet oxygen photogeneration in cell experiments, and in the model reaction of a substrate photooxidation in water. Amongst the studied polymers, CMC and PVP appeared to have the most significant influence on the photoactivity of PSs. The observed effect of the polymers on the photosensitizing activity of PSs can be attributed to the presence of chlorin-polymer interactions resulting in the porphyrin disaggregation in aqueous phase. The effect of the polymers on the photocytotoxicity of PSs is attributed to the absence of interactions between chlorin and polypeptide or lipoproteins which results in a decrease of the photoactivity of chlorins in cell culture. The PS/polymer systems appear to be a new effective dosage form of PDT drugs.

When heated with substituted allyl alcohols in acetonitrile in the presence of copper monochloride, chloral forms substituted 3,3,5-trichlorotetrahydropyrans as mixtures of diastereomers.

Chloral allyl hemiacetal undergoes cyclization in the presence of the Fe(CO)5-DMF system to form 3,3,5-trichloro-2-hydroxytetrahydropyran rather than a butyrolactone derivative.

A new highly synthetically potent series of bifunctional pyrroles, 1-vinylpyrrole-2-carbonitriles, were synthesized from readily available 1-vinylpyrrole-2-carbaldehyde oximes by two methods: (1) reaction with acetylene (KOH/DMSO, 70 °C, 10 min, yields 58–67%) and (2) reaction with acetic anhydride (90–100 °C, 5 h, yields 83–93%). Starting from 2-phenyl-1-vinylpyrrole, the one-pot synthesis of the corresponding 1-vinyl-2-carbonitrile was accomplished directly by successive treatment with a DMF/(COCl) 2 complex, NH 2 OH·HCl/NaOAc, and acetic anhydride (yield 58%).

Chloral allyl hemiacetal undergoes cyclization in the presence of the Fe(CO)5-DMF system to form 3,3,5-trichloro-2-hydroxytetrahydropyran rather than a butyrolactone derivative.

1-Vinylpyrrole-2-carbaldehydes have been selectively thiylated with ethanethiol either at the aldehyde (acid catalysis) or at the N-vinyl group (free-radical initiation) to afford 1 -vinylpyr-role-2-carbaldehyde thioacetals (88-99% yield) or 1-(2-ethylthio-ethyl)pyrrole-2-carbaldehydes (68-89% yield), respectively. Both derivatives constitute important new families of pyrrole building blocks. Exhaustive thiylation at both the aldehyde and vinyl functionalities was achieved by acid-catalyzed reaction of the ethylthioethyl derivative of pyrrole-2-carbaldehyde with ethane thiol. An unexpected reduction of the ethylthioacetal group by ethanethiol to give the ethylthiomethyl group under free-radical initiation was also observed and is discussed.

[1] We report here results of an experimental study of the OH-initiated oxidation of solid organics in the presence of O2, NOx and H2O, using two kinds of self-assembled organic monolayers (alkane and aromatic), paraffin and pyrene films as proxies for organic aerosol. We show that the OH-initiated oxidation of the alkane surfaces leads to rapid volatilization. The gas-phase products detected include HO2, H2O2, CO, CO2, HCO, CH2O, CH3CHO, CH3OH, and HCOOH. We conclude that volatilization is at least as efficient as wet deposition as a removal process for aliphatic particulates, whereas aromatic particulates show higher stability towards volatilization.

When heated with substituted allyl alcohols in acetonitrile in the presence of copper monochloride, chloral forms substituted 3,3,5-trichlorotetrahydropyrans as mixtures of diastereomers.

2-Hydroxy-3,3,5-trichlorotetrahydropyran (I), rather than the expected addition product 2,2,4-trichloro-5-hydroxypentanal, was formed as two pairs of diastereomers from the reaction of chloral with aUyl alcohol in the presence of CuCI. The structure of heteroeycle I was confirmed by tH NMR spectroscopy and by reverse synthesis: addition of chloral to allyl acetate followed by hydrolysis of the product and intramolecular cyclization of the allyl hemiacetal of chloral in the presence of CuCI: _0_ OII C13C._.~ + ~,,,,,,,~OH CuCI ~ . ~ C I