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Iron based metal organic frameworks as novel catalysts were developed for ethylbenzene synthesis by alkylation of benzene with ethanol in low temperature gas phase conditions employing MIL-101 (Fe) and MIL-88 (Fe) catalysts. Both of catalysts were synthesized with solvothermal method. Catalysts characterization were performed using X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), and Field Emission Scanning Electron Microscope (FE-SEM). Nitrogen adsorption measurements were done to determining the catalyst surface area and pore volume and pore size distribution. Also the acidity of catalysts was measured using NH 3 -TPD. The catalysts activity and product selectivity for ethylbenzene production have been investigated in a specially designed flow microreactor in gas phase. Effects of temperature and space velocity at constant benzene to ethanol ratio (3:1 volumetric ratio) have been studied for catalyst performance and ethylbenzene selectivity and yield. In comparison of two synthesized catalysts, MIL-88 showed a higher performance (100% ethanol conversion, 72% benzene conversion and 76% ethylbenzene selectivity at 175 °C). The main byproduct was recognized as toluene. Long reaction time for both catalysts showed no decline in conversion and selectivity of desired product. The BET measurement and the FTIR spectra of used catalysts revealed these Fe-based metal organic frameworks are stable catalysts for alkylation of benzene by ethanol. [ABSTRACT FROM AUTHOR]

The alkylation of toluene reaction on natural clinoptilolite was carried out in a differential fixed-bed reactor. The natural zeolite was treated under the strictly defined conditions of thermal and acidic treatments of parent rocks. Hydrothermal reaction was conducted with HCl-treated clinoptilolite at 50 °C. The acidic-clinoptilolites zeolites (AC) were modified chemically by adding silicon layers on its surface at nanometric scale. Catalytic reactions using acidic modified clinoptilolites (AMC) as catalysts were carried out at 350 to 500 °C. The ratio of reactants (toluene/ ethanol) was kept 3:1 with a flow WHSV of 2 h-1. The organic products of the reactions were analyzed by gas chromatography. High-resolution electron microscopy (HRTEM) was used to observe the modified surfaces of catalysts. The effect of chemical modification of natural clinoptilolite in the alkylation of toluene was carrying out by ethanol media. The AC showed activity to the formation of ethyltoluene. The added silicon on acidic clinoptilolite samples favored the conversion of toluene to 23 mass%. Added silicon contributed to increase the formation of ethyltoluene at 75 mass%. Catalyst test results indicated the possibility of using clinoptilolite as a raw material in the preparation of catalysts for alkylation of toluene with ethanol reaction. [ABSTRACT FROM AUTHOR]

A new method for the on-site preparation of tetrafluoroethylene (TFE) and a procedure for its efficient use in pentafluoroethylation by fluoride addition were developed by using a simple two-chamber system. The on-site preparation of TFE was accomplished by dimerization of difluorocarbene derived from (trifluoromethyl)trimethylsilane (TMSCF3) under mild conditions. Other fluoroalkylation reactions, such as (aryloxy)tetrafluoroethylation and tetrafluoroethylation processes, were also achieved using a similar approach. This work not only demonstrates a convenient and safe approach for the generation and use of TFE in academic laboratories, but also provides a new strategy for pentafluoroethylation. [ABSTRACT FROM AUTHOR]

This technical note presents optimization results of hydride generation volatilization coupled with cryogenic trapping, separation by gas chromatography and detection by cold vapor atomic fluorescence spectrometer after pyrolysis. Method performance was compared with the reference ethylation method and results from a previous study. Using GUM/Eurachem guidelines, we estimated expanded relative standard uncertainty (k = 2) of both methods. Expanded relative standard uncertainty was 11.1%, 15.0% and 21.3% for hydride generation, and 15.8%, 18.2% and 19.3% for ethylation, at the highest (> 400 fM), middle (100–150 fM) and lowest (< 50 fM) methylmercury concentration levels, respectively. Sample repeatability represents the biggest single contribution to the expanded standard uncertainty in hydride generation, together with recovery in ethylation method. [ABSTRACT FROM AUTHOR]

Fluoroalkylation reagents based on hypervalent iodine are widely used to transfer fluoroalkyl moieties to various nucleophiles. However, the transferred groups have so far been limited to simple structural motifs. We herein report a reagent featuring a secondary amine that can be converted to amide, sulfonamide, and tertiary amine derivatives in one step. The resulting reagents bear manifold functional groups, many of which would not be compatible with the original synthetic pathway. Exploiting this structural versatility and the known high reactivity toward thiols, the new-generation reagents were used in bioconjugation with an artificial retro-aldolase, containing an exposed cysteine and a reactive catalytic lysine. Whereas commercial reagents based on maleimide and iodoacetamide labeled both sites, the iodanes exclusively modified the cysteine residue. The study thus demonstrates that modular fluoroalkylation reagents can be used as tools for cysteine-selective bioconjugation. [ABSTRACT FROM AUTHOR]

A method for the copper-catalyzed pentafluoroethylation of aryl iodides using potassium (pentafluoroethyl)trimethoxyborate has been developed. The borate was found to be a convenient pentafluoroethyl source. In parallel, it was found that the solvent, as well as ligand, makes significant impact on the catalytic perfluoroalkylations. [ABSTRACT FROM AUTHOR]

S-Adenosylmethionine-dependent methyltransferases (MTs) play a decisive role in the biosynthesis of natural products and in epigenetic processes. MTs catalyze the methylation of heteroatoms and even of carbon atoms, which, in many cases, is a challenging reaction in conventional synthesis. However, C-MTs are often highly substrate-specific. Herein, we show that SgvM from Streptomyces griseoviridis features an extended substrate scope with respect to the nucleophile as well as the electrophile. Aside from its physiological substrate 4-methyl-2-oxovalerate, SgvM catalyzes the (di)methylation of pyruvate, 2-oxobutyrate, 2-oxovalerate, and phenylpyruvate at the β-carbon atom. Chiral-phase HPLC analysis revealed that the methylation of 2-oxovalerate occurs with R selectivity while the ethylation of 2-oxobutyrate with S-adenosylethionine results in the S enantiomer of 3-methyl-2-oxovalerate. Thus SgvM could be a valuable tool for asymmetric biocatalytic C-alkylation reactions. [ABSTRACT FROM AUTHOR]

An efficient Cu-catalyzed stereoselective trifluoroethylation through the decarboxylative cross-coupling of cinnamic acid derivatives with CF 3 CH 2 I is described. The ready availability of the starting materials, the high level of functional group tolerance, and excellent E selectivity make this protocol a safe and operationally convenient strategy for the efficient synthesis of trifluoroethyl derivatives. [ABSTRACT FROM AUTHOR]

The ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate [EMIM][EtOSO3] was supported on Pd-Al2O3 to yield a solid catalyst with ionic liquid layer (SCILL) material. During the hydrogenation of ethene, it was found that ethene was incorporated into the imidazolium moiety in a reaction catalyzed by the palladium surface. The formation of 1,2-diethyl-3-methylimidazolium ethylsulfate was confirmed ex situ by means of NMR spectroscopy. Moreover, the reaction itself could be monitored in situ by diffuse reflection infrared Fourier transformation (DRIFT) spectroscopy. A reaction mechanism involving surface carbene species was proposed on the basis of the analytical data. [ABSTRACT FROM AUTHOR]

[Display omitted] The immunogenicity risk of therapeutic protein aggregates has been extensively investigated over the past decades. While it is established that not all aggregates are equally immunogenic, the specific aggregate characteristics, which are most likely to induce an immune response, remain ambiguous. The aim of this study was to perform comprehensive in vitro and in vivo immunogenicity assessment of human insulin aggregates varying in size, structure and chemical modifications, while keeping other morphological characteristics constant. We found that flexible aggregates with highly altered secondary structure were most immunogenic in all setups, while compact aggregates with native-like structure were found to be immunogenic primarily in vivo. Moreover, sub-visible (1–100 µm) aggregates were found to be more immunogenic than sub-micron (0.1–1 µm) aggregates, while chemical modifications (deamidation, ethylation and covalent dimers) were not found to have any measurable impact on immunogenicity. The findings highlight the importance of utilizing aggregates varying in few characteristics for assessment of immunogenicity risk of specific morphological features and may provide a workflow for reliable particle analysis in biotherapeutics. [ABSTRACT FROM AUTHOR]

Tetrafluoroalkyl bromides are metalated with equimolar iPrMgCl·LiCl (Turbo Grignard) to form organomagnesium compounds which are stable at low temperatures and react with various electrophiles (aldehydes, ketones, CO2, cyclic sulfate and sulfamidate, N-sulfonylimines, nitrone, chlorophosphate, nonaflyl azide) to afford novel functionalized tetrafluoroethylene-containing products. Ease of operation, excellent selectivity, high nucleophilicity, and enhanced stability of the reactive species together with a broad substrate scope comprise a highly attractive nucleophilic tetrafluoroethylation protocol affording unique synthetic building blocks. [ABSTRACT FROM AUTHOR]

β-Amino alcohol and diamine ligands were prepared from isosorbide as a chiral renewable resource. The efficiencies of these ligands were evaluated for the metal-catalyzed enantioselective ethylation of aldehydes and the alkynylation of aldimines. [ABSTRACT FROM AUTHOR]

Synthesis of CF3-containing compounds is of great interest because of their broad use in the pharmaceutical and agrochemical industries. Herein, selective 2,2,2-trifluoroethylation of styrenes was catalyzed by Zr(IV)-based MOFs bearing visible-light photocatalysts in the form of Ir(III) polypyridyl complexes. When compared to the homogeneous Ir(III) catalyst, the MOF-based catalyst suppressed the dimerization of benzyl radicals, thus enhancing the selectivity of the desired hydroxytrifluoroethyl compounds. [ABSTRACT FROM AUTHOR]

Three new C19-norditerpenoid alkaloids (1-3), along with two known C19-norditerpenoid alkaloids (4-5) have been isolated from Aconitum szechenyianum. Their structures were established by extensive spectroscopic techniques and chemical methods as szechenyianine A (1), szechenyianine B (2), szechenyianine C (3), N-deethyl-3-acetylaconitine (4), and N-deethyldeoxyaconitine (5). Additionally, compounds 1-5 were tested for the inhibition of NO production on LPS-activated RAW264.7 cells with IC50 values of 36.62 ± 6.86, 3.30 ± 0.11, 7.46 ± 0.89, 8.09 ± 1.31, and 11.73 ± 1.94 μM, respectively, while the positive control drug dexamethasone showed inhibitory activity with IC50 value of 8.32 ± 1.45 μM. The structure-activity relationship of aconitine alkaloids were discussed. [ABSTRACT FROM AUTHOR]

An improved method for the preparation of pentafluoroethylating reagent pentafluoroethyl-substituted benziodoxole (BIX-C2F5) was described. Under mild conditions, BIX-C2F5 was able to react with β-ketoesters or aryl/heteroaryl boronic acids to generate pentafluoroethylated compounds in good yields. [ABSTRACT FROM AUTHOR]

The ethylation of benzene, obtained from coke oven gas, with bio-ethanol over nanosized HZSM-5 zeolite catalyst was investigated in a down-flow fixed-bed reactor. X-ray diffraction, thermogravimetric analysis, ultraviolet raman spectrophotometry, ultraviolet visible spectrophotometry, and N 2 adsorption–desorption isotherms measurements were used to characterize catalyst morphology and coke deposit over the spent catalyst. Thiophene in coking benzene promoted the formation of coke. Water contained in bio-ethanol improved the catalyst selectivity and stability, inhibited coke formation and reduced its carbonization. The water also reduced both activity and desulfurization of the catalyst. The role of water in the reaction is due to its stronger adsorption on the active sites than ethanol and thiophene in the feed. [ABSTRACT FROM AUTHOR]

This research focuses on high-value utilization of the lignin-derived phenol monomer and bioethanol from biorefining process. Supported-heteropolyacid is easily used as an efficient catalyst for the ethylation of phenol with bioethanol to obtain value-added products. Through adjusting the loading amount, different acidity amount and strength can be obtained, leading to the tunable selectivity to the phenol ethylation route and regioselectivity. [ABSTRACT FROM AUTHOR]

The crystal structure and phase transition temperature of [N(C 2 H 5 ) 4 ] 2 CuBr 4 are studied using X-ray diffraction and differential scanning calorimetry (DSC); measurements revealed a tetragonal structure and the two phase transition temperatures T C of 204 K and 255.5 K. The structural geometry near T C is discussed in terms of the chemical shifts for 1 H magic angle spinning (MAS) nuclear magnetic resonance (NMR) and 13 C cross-polarization (CP)/MAS NMR. The two inequivalent ethyl groups are distinguishable by the 13 C NMR spectrum. The molecular motions are discussed in terms of the spin–lattice relaxation times T 1ρ in the rotating frame for 1 H MAS NMR and 13 C CP/MAS NMR. The T 1ρ results reveal that the ethyl groups undergo tumbling motion, and furthermore that the ethyl groups are highly mobile. [ABSTRACT FROM AUTHOR]

Two types of allylic trifluoromethylated compounds were synthesized by reacting alkynes with CF3CH2I using visible-light photocatalysis. Subtle differences in the catalytic system controlled the selectivity of iodotrifluoroethylation and hydrotrifluoroethylation. The iodotrifluoroethylated products were obtained in the presence of [Ru(bpy)3]Cl2 and TMEDA in CH3CN under visible-light irradiation, whereas hydrotrifluoroethylated products were synthesized using fac-[Ir(ppy)3] and a mixture of DBU and K2CO3 in DMF. The iodotrifluoroethylation reaction worked particularly well, even at gram-scale, and the synthetic utility of iodotrifluoroethylated products was proved by their coupling reactions, providing complex CF3-containing products. [ABSTRACT FROM AUTHOR]

Cobalt/diamine-catalyzed 1,1-difluoroethylation and 2,2,2-trifluoroethylation of aryl Grignard reagents with 1,1-difluoroethyl and 2,2,2-trifluoroethyl halides were investigated. With regard to the 1,1-difluoroethylation, 1,2-bis(dimethylamino)-2-methylpropane, which has been rarely used in the cross-coupling reactions, gave the highest yield among the diamine ligands tested. In the 2,2,2-trifluoroethylation, trans -1,2-bis(dimethylamino)cyclohexane provided the desired products in satisfactory yields with not only 2,2,2-trifluoroethyl iodide but also chloride. This Co/diamine catalyst was also effective for the coupling with other partially fluorinated alkyl halides in the presence of appropriate diamine ligands. [ABSTRACT FROM AUTHOR]

The photolysis quantum yield, Qp, of 1-(2-nitrophenyl)ethyl phosphate (caged Pi) measured in the near-UV (342 nm peak with 60 nm half-bandwidth) is 0.53 and is based on results reported in 1978 (Biochemistry, 17, 1929–1935). This article amplifies methodology for determining that Qp in view of different recent estimates. Some general principles together with other examples relating to measurement of Qp values are discussed together with their relevance to biological research. [ABSTRACT FROM AUTHOR]

BACKGROUND Due to environmental concerns, there is a need to eliminate or drastically reduce the use of conventional organic solvents, as these are environmentally harmful. This paper reports on a novel one-pot synthesis of tetrabromoethylcyclohexane ( TBECH) in aqueous medium, using amino-functionalized ionic liquids, which catalyze the reaction and make it more environmentally friendly. RESULTS Compared with the traditional synthesis, tetrabromoethylcyclohexane is obtained with equivalent yield (90%), at room temperature, in a short reaction time (∼2 h compared with the previous 17 h) and with a strong reduction of the use of organic solvents; finally two isomers are obtained instead of four. Furthermore, a novel procedure to prepare the ionic liquids has been designed and two new ones have also been synthesised. The calculated environmental factors ( EFs), which measure the environmental sustainability, showed a strong reduction of the use of organic solvents for all syntheses of ionic liquids and TBECHs. CONCLUSIONS The excellent properties of amino-functionalized ionic liquids as solvents and catalysts for chemo- and diastereo-selective bromination of C  C bonds in water were confirmed with the synthesis of tetrabromoethylcyclohexane. Given the wide use of brominated compounds in the chemical industry, this procedure could be of wide interest. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Chemo- and stereoselectivity of the reaction of 1-[2-(vinyloxy)ethyl]-1 H-pyrroles with trifluoroacetic anhydride have been studied. The reaction with an equimolar amount of trifluoroacetic anhydride chemoselectively involves the free α-position of the pyrrole ring with formation of the corresponding α-trifluoroacetylpyrroles. In the reaction with 2 equiv of trifluoroacetic anhydride, acylation of both α-position of the pyrrole ring and β-position of the vinyloxy group leads to the formation of 1-(2-{[(1 E)-4,4,4-trifluoro-3-oxobut-1-en-1-yl]oxy}ethyl)-2-trifluoroacetyl derivatives with high stereoselectivity. [ABSTRACT FROM AUTHOR]

Three-component condensation of diethyl 2-oxobutanedioate sodium salt with aromatic aldehydes and tetrazol-5-amine monohydrate afforded the corresponding diethyl 6-aryl-3,6-dihydrotetrazolo[1,5- a]pyrimidine-4,5-dicarboxylates. [ABSTRACT FROM AUTHOR]

Three-component condensation of N, N-diethyl-3-oxobutanamide with aromatic aldehydes and thiourea afforded the corresponding 6-aryl- N, N-diethyl-4-methyl-2-sulfanylidene-1,2,3,6-tetrahydropyrimidine-5-carboxamides. [ABSTRACT FROM AUTHOR]

Background: Adaptive response has been well studied by employing physical and chemical agents in normal test systems, whereas in diseased conditions very little data are available. Aim of the study: To know the presence or absence of adaptive response in diseased condition, alkylating agents such as EMS or MMS have been employed in diabetic mouse. Material and methods: To induce diabetes, mice were injected with 180 mg/kg body weight of Stz. Diabetic mice were treated with conditioning (100 mg/kg body weight of EMS or 40 mg/kg body weight of MMS), challenging (300 mg/kg body weight of EMS or 160 mg/kg body weight of MMS) and combined doses of EMS or MMS with 8 h time lag. Parallelly controls were maintained. Mice were sacrificed at 24 or 48 or 72 h RTs. Bone marrow was extracted and slides were prepared by a routine air dry technique by Evans et al. (1964) to analyze the chromosomal aberrations. Results: The results show that both the alkylating agents induced exclusively chromatid type of aberrations in both diabetic and non diabetic mice, but it is to be underlined that MMS is a more potent inducer of aberrations than EMS. Eventhough, combined treatment of EMS or MMS induced significantly less chromosomal breaks compared to challenging treatment (p< 0.05) in diabetic mice, EMS induced 40% reduction of breaks, compared to 51.74% by MMS at 24 h RT. This is true to other tested RTs. Conclusion: (1) Methylating agents are a more effective inducer of adaptive response than ethylating agents in diabetic mouse. (2) Further, it is interesting to note that the percentage reduction of chromosomal breaks in diabetics is comparatively much less than in non diabetic mouse, inferring that there is variation in adaptive response between diseased and non diseased condition. [ABSTRACT FROM AUTHOR]

We report a highly stereocontrolled total synthesis of one of the possible stereoisomers of laurenidificin. Highlights of the synthesis include the formation of the 2,6-dioxabicyclo[3.3.0]octane framework by a stereospecific bromolactonization-a-bromination-ring contraction sequence, followed by a stereoselective propargylation, an insertion of the Z-enyne side chain by a hydroindation/cross coupling reaction, and ethylation at C13 with an organocuprate reagent. While the synthetic compound was not identical to the natural product, the absolute stereochemistry of the natural product was proposed on the basis of NMR analyses. Moreover, a formal total synthesis of (+)-aplysiallene was achieved by extending the ring contraction strategy. [ABSTRACT FROM AUTHOR]

Using alkyl 4,5-bis(diethoxyphosphorylmethyl)furan-3-carboxylate as examples, we have demonstrated the possibility of synthesis of a phosphorylated analog of aglycone of the glycoside regulator of cellulose and callose synthesis, bis(phosphorylated) furoyl derivatives of natural amino acids, and phosphorus-containing derivatives of N-furyl- N′-hydroxyethylurea; these compounds are of interest for pharmacology. [ABSTRACT FROM AUTHOR]

The mechanism of the photodecomposition of the long lived radical [(CF 3 ) 2 CF] 2 C C 2 F 5 is explored by UV and ESR spectroscopy and quantum chemical calculations. The kinetics of the photodecomposition of [(CF 3 ) 2 CF] 2 C C 2 F 5 are investigated in a matrix of glassy and liquid hexafluoropropylene trimer at 77 and 300 K, respectively. The mechanism of [(CF 3 ) 2 CF] 2 C C 2 F 5 photodecomposition does not depend on the phase state of the matrix but differs from the thermal decomposition of the radical. Under UV light with λ < 300 nm, the CF 2 CF 3 bond of the perfluoro-ethyl group of [(CF 3 ) 2 CF] 2 C C 2 F 5 is broken. Thermal decomposition of the radical above 373 K occurs by breaking a CF CF 3 bond in the perfluoro-isopropyl group. The experimental results are consistent with the calculated bond dissociation energies and UV–vis excitation spectra of the radical. Additional calculated C C BDEs for a number of fluorocarbon radicals show that radicals can be designed with very low C C BDEs for the generation of CF 3 radicals. [ABSTRACT FROM AUTHOR]

Alkylation of isopropylidene- and cyclohexylidenepropanedinitrile with phenacyl bromides gave 2,2-bis(2-aryl-2-oxoethyl)propanedinitriles. Direct alkylation of propanedinitrile with phenacyl bromides afforded only 2-(2-aryl-2-oxoethyl)propanedinitriles. [ABSTRACT FROM AUTHOR]

Novel tridentate ligands were prepared from (+)-camphoric acid, using simple synthetic sequences. The synthesized ligands were used in enantioselective ethylations of benzaldehydes, showing enantioselectivities up to 92%, at room temperature. Extending the reaction to other aromatic aldehydes, very good results (almost quantitative yields and ee up to 97%, for m -anisaldehyde) were obtained. Structural features such as no substitution in the salicylaldehyde moiety of the Schiff base and an ethyl group in the nitrogen at the C1 position of the cyclopentane ring seem to be essential for obtaining high enantioselectivities. [ABSTRACT FROM AUTHOR]

A general and efficient one-pot aminoethylation of substituted indoles/pyrroles was accomplished for the synthesis of various tryptamine derivatives employing a combination of alkynes and sulfonyl azides as readily accessible aminoethylating agents. The reaction features a successful integration of copper-catalyzed alkyne and azide cycloaddition to N-sulfonyl-1,2,3-triazole, rhodium-catalyzed selective insertion of α-iminocarbenes onto the C3H bond of indoles, and reduction of the resultant enamides to tryptamine derivatives employing either NaCNBH3 or palladium catalyst, in one-pot. The reaction also showed excellent functional-group tolerance and allowed the synthesis of various substituted tryptamines in good to excellent yield. This transformation constitutes a one-pot formal regioselective functionalization of terminal alkynes. Utility of the synthesized tryptamine was further demonstrated in the synthesis of dihydro-β-carboline and tryptoline. [ABSTRACT FROM AUTHOR]

A novel and mild fluorination/cyclization reaction of activated alkenes under metal-free conditions has been developed. Fluorinated radicals were produced from halogenated hydrocarbons by simple rongalit, meanwhile, no metal and extra base are needed. This method provides a general and rapid route to construct fluorinated 2-oxindoles in aqueous solution. [ABSTRACT FROM AUTHOR]

A direct and efficient approach for the trifluoromethylation and pentafluoroethylation of 1,1-diaryl-2,2-difluoroethenes with TMSCF 3 and TMSCF 2 CF 3 in the presence of TBAF was developed. The reactions proceeded smoothly under mild reaction conditions to give the corresponding monotrifluoromethylated, bistrifluoromethylated, monopentafluoroethylated and bispentafluoroethylated products in fair to good yields, respectively, without the addition of metal catalyst. [ABSTRACT FROM AUTHOR]

The visible-light-induced photoredoxdifunctionalization reactionsof styrenes with 1,1,1-trifluoro-2-iodoethane under an oxygen atmospherein the presence of water give γ-trifluoromethyl alcohols. Inthis radical reaction, the oxygen atom in the product originates frommolecular oxygen, and water is shown to be important to promote thereaction. [ABSTRACT FROM AUTHOR]

Synthesis, crystal structure, vibrational study and magnetic properties of the compound (CHN) CuCl are reported. The latter crystallizes in the monoclinic system (space group P2, Z = 4) with the following unit cell dimensions: a = 7.569(5) Å b = 14.174(5) Å, c = 13.193(2) Å and β = 105.53(3). Besides, its structure was solved using 5754 independent reflections down to R = 0.0475. The atomic arrangement can be described by alternating organic and inorganic layers stacked in the [ $\bar {1}$01] direction, made up of tetrahedral of tetrachlorocuprate CuCl $_{4}^{2-}$ sandwiched between two organic layers. In crystal structure, the inorganic layer, built up by independent monomeric [CuCl], is connected to the organic ones through hydrogen bonding in order to build a three-dimensional network. The magnetic behavior of (CHN) CuCl samples was investigated as a function of temperature and applied field. At hightemperature paramagnetic behavior, and at low temperature, evidence for weak ferromagnetism, reinforced by a hysteresis loop at 2 K is observed. The magnetic behavior of (CHN) CuCl is attributed to Cu (II) due to the presence of an active Jahn-Teller effect in the d electronic system, which give rise to short-range weak ferromagnetism. [ABSTRACT FROM AUTHOR]

ABSTRACT Branched polyethyleneimine (bPEI) was used to modify the surface of Fe3O4 nanoparticles coated with silica layer, and then, it was treated with ethyl iodide to prepare Fe3O4@SiO2@Ethylated-bPEI. In the next step, the yolk-shell structure was gained by selectively etching the SiO2 middle layer. Finally, copper(I) was introduced to the yolk-shell Fe3O4@Ethylated-bPEI and the activity of the catalyst was evaluated for atom transfer radical polymerization (ATRP) of styrene, led to obtain the well-defined polymer with relatively low polydispersity. The toxicity of the residual copper in the polymer product was a limiting issue for applicability of ATRP reactions especially for biological purposes. In this report, the copper content in the polymer was reduced to the excellent value of 1.1 ppm. Moreover, the magnetic isolation, recyclability, and remove the need for an external ligand were other advantages of the synthesized catalyst which makes it suitable for employing in ATRP reactions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42337. [ABSTRACT FROM AUTHOR]

The evaluation of the photorelease of a carboxylic acid drug, using butyric acid as a representative model, was carried out by using 7-amino-4-chloromethyl-2-oxo-2H-naphtho[1,2-b]pyran, an aminobenzocoumarin, and its mono- and di-methylated or ethylated derivatives. This study was intended to improve the release of butyric acid from benzocoumarins by the addition of an amino group to the heterocycle by applying the knowledge of second-generation coumarinylmethyl-based photoremovable protecting groups. Photolysis studies were performed on the resultant ester cages by irradiation in a photochemical reactor at 254, 300, 350 and 419 nm, using methanol/HEPES buffer 80 : 20 solutions as solvent. The data obtained showed that these new fluorescent aminobenzocoumarins are superior to all the previously tested benzocoumarins with the same or different ring fusions. The photophysics of the compounds was characterised by both steady state and time-resolved methods. [ABSTRACT FROM AUTHOR]

Successful benzylic C(sp3)H trifluoromethylation, pentafluoroethylation, and heptafluoropropylation of six-membered heteroaromatic compounds were achieved as the first examples of a practical benzylic C(sp3)H perfluoroalkylation. In these reactions, BF2C nF2 n+1 ( n=1-3) functioned as both a Lewis acid to activate the benzylic position and a C nF2 n+1 ( n=1-3) source. The perfluoroalkylation proceeded at both terminal and internal positions of the alkyl chains. Perfluoroalkylated products were obtained in moderate to excellent yields, even on gram scale, and in a sequential procedure without isolation of the intermediates. By using this method, trifluoromethylation of a bioactive compound, as well as introduction of a CF3 group into a bioactive molecular skeleton, proceeded regioselectively. [ABSTRACT FROM AUTHOR]

A novel route for the environmentallyfriendly synthesis of diethyltoluene diamine (DETDA) was developed by the ethylation of 2,4-toluenediamine (2,4-TDA) over acidic zeolites using ethene and ethanol asthe alkylation reagents. Different types of zeolites and reactionconditions were examined. Monoethyl toluene diamine (ETDA) was firstgenerated and then DETDA was formed by ethylation of ETDA. Triethyltoluene diamine (TETDA) was the excessive ethylation product. Theacidic zeolites were characterized by NH3temperature-programmeddesorption, pyridine adsorption Fourier transform infrared spectroscopy,argon/nitrogen physisorption and scanning/transmission electron microscopy.The acidity, especially the Brønsted acid sites on the externalsurface of zeolites, plays a more important role in the ethylationthan the pore channel does. A small crystal size exposing more acidsites on the external surface is beneficial for the producing of DETDA.The treatment with NaOH generating meso- and macropores and increasingexternal surface area can also improve the catalytic activity of ZSM-5. [ABSTRACT FROM AUTHOR]

A homopolymer strategy was developed to synthesize temperature and pH/CO 2 stimulus-responsive homopolymers. A new class of acrylamide monomers bearing oligo(ethylene glycol) unit and N,N -diethylaminoethyl group were designed and prepared through Aza-Michael addition reaction followed by amidation with acryloyl chloride using amino group as a linkage to connect oligo(ethylene glycol), N,N -diethylaminoethyl, and polymerizable double bond groups together. Subsequently, the corresponding homopolymers containing oligo(ethylene glycol) unit and N,N -diethylaminoethyl group in each repeated unit were prepared via RAFT polymerization with controlled molecular weights and relatively narrow molecular weight distributions. The lower critical solution temperature (LCST) of homopolymer was examined to be influenced by molecular weight, salt concentration, and pH value of aqueous solution. The LCSTs of homopolymers could be tuned in a wide temperature window by changing pH value of aqueous solution and it increased with the decrease of pH value. Particularly, CO 2 gas as a unique pH stimulus can also reversibly adjust the solubility of homopolymer without the addition of acids or bases. [ABSTRACT FROM AUTHOR]

Four new well-defined CuI complexes bearing a C2F5 ligand have been prepared and fully characterized: [(Ph3P)2CuC2F5] ( 2), [(bpy)CuC2F5] ( 3), [(Ph3P)Cu(phen)C2F5] ( 4), and [(IPr*)CuC2F5] ( 5). X-ray structures of all four have been determined, showing that the C2F5-ligated Cu atom can be di- ( 5), tri- ( 2 and 3), and tetracoordinate ( 4). The mixed phen-PPh3 complex 4 is a highly efficient fluoroalkylating agent for a broad variety of acid chlorides. This high-yielding transformation represents the first general method for the synthesis of RCOC2F5 from the corresponding RCOCl. [ABSTRACT FROM AUTHOR]

Novel neutral guest molecules, G1–G7, are studied for their host–guest complexation with per-ethylated pillar[5]arene (EtP[5]A). Among them, G1 and G7, dibenzyl tetramethylene bis-carbamate derivatives, are found to afford a novel stable pseudo[2]rotaxane with EtP[5]A, respectively, and G7⊂EtP[5]A shows photoresponsive properties. [ABSTRACT FROM AUTHOR]

A new evaporable electron acceptor material for organic photovoltaics based on N-ethyl barbituric acid bithiophene (EBB) has been demonstrated. Bilayer devices fabricated with this non-fullerene acceptor and boron subphthalocyanine chloride (SubPc) donor produce power conversion efficiencies as high as 2.6% with an extremely large open-circuit voltage approaching 1.4 V. [ABSTRACT FROM AUTHOR]

A novel highly C3 selective metal free trifluoroethylation of indoles using 2,2,2-trifuoroethyl(mesityl)-iodonium triflate was developed. The methodology enables the introduction of a trifluoroethyl group in a fast and efficient reaction under mild conditions with high functional group tolerance. Beyond the synthetic developments, quantum chemical calculations provide a deeper understanding of the transformation. [ABSTRACT FROM AUTHOR]

A new class of quinazoline-based enantiomerically pure aziridine diols 4a – d were prepared from the aziridination of mesityl oxide 3 with in situ generated 3-acetoxyaminoquinazolinone ( S )- 2b followed by NaBH 4 reduction. Aziridine diols 4a – d were purified by means of column chromatography on silica gel and their stereochemistries were assigned by X-ray crystallography and NMR analysis. These aziridine diols 4 were evaluated as chiral ligands in the asymmetric addition of diethylzinc to aryl aldehydes, and ligand ( S , R , R )- 4a yielded ( R )-1-phenylpropanol derivatives with up to 92% ee, while the diastereomer ( S , S , R )- 4c gave the opposite enantiomers ( S )-1-phenylpropanol derivatives with up to 86% ee. The results demonstrate that switching the configuration of the aziridine alcohol moiety in ligand gives a remarkable reversal of enantioselectivity in the asymmetric addition of diethylzinc to aryl aldehydes. [ABSTRACT FROM AUTHOR]