Abstract  Removal of aromatic pollutants from water by using polymeric adsorbents has been of great interest. In this paper, adsorption of 2,3-dimethylphenol and 2,4,6-trimethylphenol from aqueous solution onto a poly(styrene-co-divinylbenzene) functionalized with isopropyl-aminophosphonic acid group at temperatures of 20 degrees C, was studied.

Abstract  Mycoplasma hyopneumoniae is the cause of enzootic pneumonia in pigs, a chronic respiratory disease associated with significant economic losses to swine producers worldwide. The molecular pathogenesis of infection is poorly understood due to the lack of genetic tools to allow manipulation of the organism and more generally for the Mycoplasma genus. The objective of this study was to develop a system for generating random transposon insertion mutants in M. hyopneumoniae that could prove a powerful tool in enabling the pathogenesis of infection to be unraveled. A novel delivery vector was constructed containing a hyperactive C9 mutant of the Himar1 transposase along with a mini transposon containing the tetracycline resistance cassette, tetM. M. hyopneumoniae strain 232 was electroporated with the construct and tetM-expressing transformants selected on agar containing tetracycline. Individual transformants contained single transposon insertions that were stable upon serial passages in broth medium. The insertion sites of 44 individual transformants were determined and confirmed disruption of several M. hyopneumoniae genes. A large pool of over 10 000 mutants was generated that should allow saturation of the M. hyopneumoniae strain 232 genome. This is the first time that transposon mutagenesis has been demonstrated in this important pathogen and could be generally applied for other Mycoplasma species that are intractable to genetic manipulation. The ability to generate random mutant libraries is a powerful tool in the further study of the pathogenesis of this important swine pathogen.

Abstract  INTRODUCTION: Participation in clinical trial (CT) research can help decrease health disparities in rural communities. The purpose of this study was to examine the perceptions of principal investigators (PIs) regarding CT participation barriers and recruitment efforts in rural South Carolina, USA and to assess the actual pool of potential CT participants in rural and urban South Carolina. The ultimate goal was to evaluate the fit between PIs' perceptions and the pool of eligible participants in rural South Carolina.

METHODS: An online survey was conducted with 119 CT PIs from South Carolina's five main academic medical centers located in urban areas of the state, for a response rate of 31%. Secondary data analyses were also conducted using data from government health insurance plans, including the 2009 South Carolina Medicaid, the 2009 State Health Plan (SHP) data, and census data from the 2005-2009 American Community Survey (ACS). Both parametric and non-parametric statistics were used to analyze survey and secondary data.

RESULTS: Principal investigators perceived greater recruitment barriers in rural areas than in the general population. They indicated having difficulty finding CT participants in rural areas compared to the general population (t= -2.985, p=0.004). Rural residents were significantly more likely to be perceived as lacking knowledge and understanding about CT than the general public (t= -2.105, p=0.038), having significantly lower literacy than the general public (t= -2.058, p=0.043), lacking information about available CTs (t= -2.913, p=0.005), and having limited accessibility to trial sites compared to the general population (t= -4.380, p=0.000). Patients' insurance coverage, however, was not found to be a significant barrier for CT participation (t=0.418, p=0.677). Secondary data variables were aligned with these barriers. Data revealed that rural residents have slightly lower educational attainment than urban citizens >t=5.384, p=0.000), and more people live below poverty level in rural areas (23%) than in urban areas (15%) (t=4.86, p=0.000). The secondary data analyses also showed that the majority of rural citizens covered by the SHP and Medicaid are eligible for CTs. ACS data revealed that 75% of people in rural areas meet one or more basic eligibility requirements to participate in CTs compared to 83% in urban areas.

CONCLUSIONS: Some important barriers hinder CT enrollment of rural participants, such as accessibility to trial sites, poverty, lack of knowledge about CTs, among others. Data suggested that insurance coverage, however, is not a barrier to CT participation. Although CT PIs are correct in considering these barriers in rural areas, there still exists a large pool of potentially eligible CT participants in rural South Carolina. PIs, who were recruited from urban academic medical centers, may therefore be perpetuating unhelpful rural myths about CT eligibility in rural communities. Despite their remote locations, rural citizens should take part in medical research. Greater communication between PIs and rural participants and better education of PIs on communication strategies are needed to enhance CT participation in rural South Carolina.

Abstract  Dinuclear square planar palladium(ii) complexes, [{Pd(ii)La}2(baet)] (La(-) = β-diketonato and baet(2-) = 1,2-diacetyl-1,2-bis(3-methylbutanoyl)ethanato), were prepared and used as chiral dopants to induce chiral nematic phases. The following β-diketones were used as LaH: pentane-2,4-dione (acacH), dibenzoylmethane (dbmH), di-4-nonyloxybenzoylmethane (C9-dbmH) and 3-[4'-(4''-(octyloxy)phenylazo)phenyl]-2,4-dione (C8-azoacacH). When the enantiomers were doped in a nematic liquid crystal, they induced a chiral nematic phase with a helical twisting power (HTP) of 5-50 μm(-1). In particular, the sample doped with [{Pd(ii)(C8-azoacac)}2(baet)] exhibited a reversible change of the circular dichroism spectrum under alternate irradiation at 350 nm and 460 nm. It implied that the HTP changed reversibly in response to the cis-trans isomerization of the coordinated C8-azoacac ligand.

Abstract  Computational studies carried out at density functional theory levels are able to provide reliable chemical information about medium sized compounds as anthocyanins and their aglycons (anthocyanidins). Thus, they indicate that the most stable tautomers in aqueous solution for the main anthocyanidins (excluding pelargonidin) are deprotonated at C4' in the neutral forms, while deprotonations at C5 and C4' characterize the most stable anions in solution. QTAIM electron density analysis (overviewed in brief in the methods section) shows that Lewis structures usually employed give rise to unreliable atomic charges. Thus: (1) The positive charge spreads throughout the whole cation, and is not localized on any specific atom or set of atoms; (2) Neutral forms can be described as enolates where the negative charge is counterbalanced in a different way to that indicated by the typical resonance forms; and (3) The negative charge of anions is mainly spread among three regions of the molecule: the two deprotonated sites and the C9-O1-C2 area. The analysis of a group of complexes formed by a model of cyanin with four common metalic cations (Mg(II), Al(II), Cu(II), Zn(II)), shows: (1) the preference for tetracoordination in Zn(II) and Cu(II) complexes, (2) higher affinity for Cu(II) than for the other metals here studied, and (3) the distortion of electron density in the cyanin ligand affects the whole molecule. This distortion can be described as a continuous polarization where, even, in some cases, the atomic electron populations of those atoms of the ligand that are more directly involved in bonding to the metal increase.

Abstract  In the present study, an accomplished reaction network is developed for commercial conversion of heavy reformates to more valuable xylenes. The proposed kinetic model is based on 18 pseudo-components and 39 related reactions in which 7 different types of reactions are included. Thermodynamic principles are also applied to predict the reversibility of the reactions. To estimate the reaction rate constants, the absolute deviation between the model results and observed data are minimized applying differential evolution (DE) optimization method. To prove the accuracy of the proposed model, simulation results are compared with the plant data and an acceptable agreement is achieved. Then, the effect of operating conditions on the reactor performance is verified. The results of this work show that increasing the inlet temperature and molar flow rate up to certain values would improve the xylenes production. (C) 2014 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Abstract  Enthalpies of solution at infinite dilution of 48 organic solutes in mesitylene and 81 organic solutes in p-xylene were measured using isothermal solution calorimeter. Enthalpies of solvation for 92 organic vapors and gaseous solutes in mesitylene and for 130 gaseous compounds in p-xylene were determined from the experimental and literature data. Abraham model correlations are determined from the experimental enthalpy of solvation data. The derived correlations describe the experimental gas-to-mesitylene and gas-to-p-xylene solvation enthalpies to within average standard deviations of 1.87 kJ mol(-1) and 2.08 kJ mol(-1) respectively. Enthalpies of X-H center dot center dot center dot pi (X-O, N, and C) hydrogen bond formation of proton donor solutes (alcohols, amines, chlorinated hydrocarbons etc.) with mesitylene and p-xylene were calculated based on the Abraham solvation equation. Obtained values are in good agreement with the results determined using conventional methods. (C) 2014 Elsevier B.V. All rights reserved.

Abstract  The atmospheric oxidation mechanism of 1,2,4-trimethylbenzene (1,2,4-TMB) initiated by OH radicals is investigated using quantum chemistry calculations at M06-2X and ROCBS-QB3 levels. The calculations show that the initiation of the reaction is dominated by OH addition to C1, C3 and C5 to form 1,2,4-TMB-OH adducts R1, R3, and R5 with branching ratios of 0.22, 0.19, and 0.38, respectively, using ROCBS-QB3 energies. In the troposphere, the adducts react with O2 by irreversible H-abstraction to form phenolic compounds and by reversible addition to TMB-OH-O2 peroxy radicals, which will cyclize to bicyclic radicals, similar to those in benzene, toluene, and xylenes. The bicyclic radicals can further recombine with O2 to generate bicyclic peroxy and alkoxyl radicals. The bicyclic alkoxyl radicals would break the ring directly to form 1,2-dicarbonyl products and unsaturated 1,4-dicarbonyl co-products, or undergo another cyclization to form an epoxy group, followed by the ring-breakage to form 1,2-dicarbonyl products and epoxy-1,4-dicarbonyl co-products. The predicted yields of products agree reasonably with the previous experimental measurements, while considerable discrepancies also exist for the yields of nitrates, biacetyl, 4-oxo-2-pentenal, and butenedial, etc. Our mechanism also predicts a new type of epoxy-1,4-dicarbonyl compounds with a total yield of ∼0.32. The epoxy-1,4-dicarbonyl compounds have not been suggested or reported in previous studies.

Abstract  Starting from a flexible tri-carboxylic acid ligand H3L {H3L = 2,4,6-tris[(4-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene}, a 3D metal-organic framework [Zn(HL)(H2O)](n) (1) and a 2D polymeric layered solid {[(CH3)(2)NH2)](2)[Cd2L2(DMA)(2)]}(n) (2) were hydrothermally synthesized. The complexes were characterized by elemental analyses, FT-IR spectroscopy, TGA, and single-crystal X-ray diffraction. The X-ray structural analyses reveal that the complex 1 is an example of a doubly interpenetrated 3D helical MOF with mutually entwined right- and left-handed helices to form an overall racemic framework. Complex 2 is made up of fourfold interwoven 2D nets in the solid state.

Abstract  Hierarchically porous silica monoliths with well-defined interconnected macropores and uniform spherical mesopores were spontaneously prepared by combining polymerization-induced phase separation with an epoxide-mediated sol-gel route without any complicated aging and drying and high-temperature heat treatment. The precise control of pore structures can be realized by using propylene oxide (PO) as the gelation mediation agent, poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (P123) as the phase-separation inducer as well as the structure-directing agent and 1,3,5-trimethylbenzene (TMB) as the micelle-swelling agent. The as-prepared silica monolith possesses an interesting hierarchically porous structure constructed by 10 nm uniform spherical mesopores confined in a macroporous framework of well-defined 1 μm macropores, and exhibits a BET surface area as high as 848 m(2) g(-1). Heat treatment at 400-800 °C gradually decreases the BET surface area to 195 m(2) g(-1), while most of the uniform mesoporous structure remains intact.

Abstract  Aconitum vilmorinianum Komarov is a local medicinal plant used in many well-known clinical preparations to treat rheumatism and pains in Yunnan Province, China. Phytochemical examination of the roots of A. vilmorinianum led to the isolation of three novel imine-type norditerpenoid alkaloids named vilmorrianines E-G (1-3), and a new natural alkaloid N-desethyl-N-formyl-8-O-methyltalatisamine (4), together with 14 known alkaloids. Their structures were elucidated on the basis of spectroscopic evidence. Vilmorrianine E is the first known norditerpenoid alkaloid containing both an imine group and a three-membered ring formed by C8, C9, and C10.

Abstract  Oxidation of 2-methoxy-p-cresol, p-cresol, 2-bromo-p-cresol to their corresponding 4-hydroxybenzaldehydes with atmospheric molecular oxygen as oxidant and a combination of cobaltous chloride and N-hydroxyphthalimide (NHPI) as catalyst in methanol has been investigated for the first time. The results indicated that the reaction progress was related to the substituents in the structures of the substrates: the electron-donating group methoxy favors the aerobic reaction but the electron-withdrawing group Br is detrimental to the reaction. The introduction of salen-Cu(II) complexes as the third component into the cobaltous chloride/NHPI catalytic system can considerably improve the aerobic oxidation of p-cresol and 2-brom-p-cresol to the corresponding 4-hydroxybenzaldes.

Abstract  Intraerythrocytic development of the human malaria parasite Plasmodium falciparum appears as a continuous flow through growth and proliferation. To develop a greater understanding of the critical regulatory events, we utilized piggyBac insertional mutagenesis to randomly disrupt genes. Screening a collection of piggyBac mutants for slow growth, we isolated the attenuated parasite C9, which carried a single insertion disrupting the open reading frame (ORF) of PF3D7_1305500. This gene encodes a protein structurally similar to a mitogen-activated protein kinase (MAPK) phosphatase, except for two notable characteristics that alter the signature motif of the dual-specificity phosphatase domain, suggesting that it may be a low-activity phosphatase or pseudophosphatase. C9 parasites demonstrated a significantly lower growth rate with delayed entry into the S/M phase of the cell cycle, which follows the stage of maximum PF3D7_1305500 expression in intact parasites. Genetic complementation with the full-length PF3D7_1305500 rescued the wild-type phenotype of C9, validating the importance of the putative protein phosphatase PF3D7_1305500 as a regulator of pre-S-phase cell cycle progression in P. falciparum.

Abstract  The energy-efficient separation of chemical feedstocks is a major sustainability challenge. Porous extended frameworks such as zeolites or metal-organic frameworks are one potential solution to this problem. Here, we show that organic molecules, rather than frameworks, can separate other organic molecules by size and shape. A molecular organic cage is shown to separate a common aromatic feedstock (mesitylene) from its structural isomer (4-ethyltoluene) with an unprecedented perfect specificity for the latter. This specificity stems from the structure of the intrinsically porous cage molecule, which is itself synthesized from a derivative of mesitylene. In other words, crystalline organic molecules are used to separate other organic molecules. The specificity is defined by the cage structure alone, so this solid-state 'shape sorting' is, uniquely, mirrored for cage molecules in solution. The behaviour can be understood from a combination of atomistic simulations for individual cage molecules and solid-state molecular dynamics simulations.

Abstract  The enantioselective total synthesis of the bioactive marine natural products pinnaic acid and halichlorine is reported in detail. Our total synthesis features the construction of the five-membered ring and C9 and C13 stereogenic centers through a palladium-catalyzed trimethylenemethane [3+2] cyclization; the installation of the nitrogen atom through a regioselective Beckmann rearrangement of a poorly reactive ketone; the stereoselective cyclization of the spiro ring through a four-step, one-pot hydrogenation-cyclization; and efficient connection of the sterically hindered lower chain through a reduced-pressure cross olefin metathesis reaction.

Abstract  Small cell lung cancer (SCLC) is an aggressive type of lung cancer, and the detection of SCLCs at an early stage is necessary for successful therapy and for improving cancer survival rates. Fucosylation is one of the most common glycosylation-based modifications. Increased levels of fucosylation have been reported in a number of pathological conditions, including cancers. In this study, we aimed to identify and validate the aberrant and selective fucosylated glycoproteins in the sera of patients with SCLC. Fucosylated glycoproteins were enriched by the Aleuria aurantia lectin column after serum albumin and IgG depletion. In a narrowed down and comparative data analysis of both label-free proteomics and isobaric peptide-tagging chemistry iTRAQ approaches, the fucosylated glycoproteins were identified as up- or down-regulated in the sera of limited disease and extensive disease stage patients with SCLC. Verification was performed by multiple reaction monitoring-mass spectrometry to select reliable markers. Four fucosylated proteins, APCS, C9, SERPINA4, and PON1, were selected and subsequently validated by hybrid A. aurantia lectin ELISA (HLE) and Western blotting. Compared with Western blotting, the HLE analysis of these four proteins produced more optimal diagnostic values for SCLC. The PON1 protein levels were significantly reduced in the sera of patients with SCLC, whereas the fucosylation levels of PON1 were significantly increased. Fucosylated PON1 exhibited an area under curve of 0.91 for the extensive disease stage by HLE, whereas the PON1 protein levels produced an area under curve of 0.82 by Western blot. The glycan structural analysis of PON1 by MS/MS identified a biantennary fucosylated glycan modification consisting of a core + 2HexNAc + 1Fuc at increased levels in the sera of patients with SCLC. In addition, the PON1 levels were decreased in the sera of the Lewis lung carcinoma lung cancer mouse model that we examined. Our data suggest that fucosylated protein biomarkers, such as PON1, and their fucosylation levels and patterns can serve as diagnostic and prognostic serological markers for SCLC.

Abstract  The mosquito-borne alphavirus, chikungunya virus (CHIKV), has recently reemerged, producing the largest epidemic ever recorded for this virus, with up to 6.5 million cases of acute and chronic rheumatic disease. There are currently no licensed vaccines for CHIKV and current anti-inflammatory drug treatment is often inadequate. Here we describe the isolation and characterization of two human monoclonal antibodies, C9 and E8, from CHIKV infected and recovered individuals. C9 was determined to be a potent virus neutralizing antibody and a biosensor antibody binding study demonstrated it recognized residues on intact CHIKV VLPs. Shotgun mutagenesis alanine scanning of 98 percent of the residues in the E1 and E2 glycoproteins of CHIKV envelope showed that the epitope bound by C9 included amino-acid 162 in the acid-sensitive region (ASR) of the CHIKV E2 glycoprotein. The ASR is critical for the rearrangement of CHIKV E2 during fusion and viral entry into host cells, and we predict that C9 prevents these events from occurring. When used prophylactically in a CHIKV mouse model, C9 completely protected against CHIKV viremia and arthritis. We also observed that when administered therapeutically at 8 or 18 hours post-CHIKV challenge, C9 gave 100% protection in a pathogenic mouse model. Given that targeting this novel neutralizing epitope in E2 can potently protect both in vitro and in vivo, it is likely to be an important region both for future antibody and vaccine-based interventions against CHIKV.

Abstract  Aurones are an important type of flavonoids with broad biological activities and pharmacological effects, such as anti-tumor, anti-inflammatory, antioxidant, antibacterial, insect antifeedant etc. They are less common and not widely distributed in nature. The low contents in nature lead to high cost of extraction and separation. In order to extend the compounds diversity and study structure activity relationship, phenoxyacetic acid, 2,3,5-trimethylphenol, 4-chlorol-3,5-dimethylphenol, chloroacetic acid and various aromatic aldehydes are used as starting materials to synthesize three types of aurone derivatives. Their structures were characterized by melting point, H-1 NMR, C-13 NMR, ESI-MS and elemental analysis. Nine of twenty five synthetic compounds 2h similar to 2m, 5a similar to 5c were unreported in the literature. All the target compounds were evaluated for antitumor activities against Hela human cervical carcinoma cell lines by methyl thiazolyl tetrazolium (MTT) method. The results showed that compounds 2b, 5b, 2s and 2g exhibited potentially high activity against Hela human cervical carcinoma cell lines with IC50 value of 44.3, 31.1, 43.8 and 41.9 mu mol/L.

Abstract  JP-8, which is an aviation fuel, was accepted as a common military fuel towards the end of 1980s by NATO countries. JP-8 containig 99.8% kerosene is blended with various additives to make it suitable for military applications. The most important feature having a freezing point of below -40 degrees C. The purpose of this study is to investigate the possibility of using JP-8 and referance diesel fuel blends. In this study JP-8 was added to diesel fuel with volumetric ratios of % 5, % 10, % 25 ve % 50. Experiments were carried out in a single cylinder, four-stroke and direct injection diesel engine. According to the test results engine performance and exhaust emission characteristics were investigated and compared with the reference diesel fuel. Engine torque decreased and brake specific fuel consumption increased by using JP-8 blends according to the reference diesel fuel. While CO and smoke emissions increased, NOx emissions decreased with JP-8 blends when compared with diesel fuel.

Abstract  Efficient photocatalytic oxygenation of toluene occurs under visible light irradiation of 9-mesityl-10-methylacridinium (Acr(+)-Mes) in oxygen-saturated acetonitrile containing toluene and aqueous hydrochloric acid with a xenon lamp for 15 h. The oxygenated products, benzoic acid (70 %) and benzaldehyde (30 %), were formed after the photoirradiation. The photocatalytic reaction is initiated by intramolecular photoinduced electron transfer from the mesitylene moiety to the singlet excited state of the Acr(+) moiety of Acr(+)-Mes, which affords the electron-transfer state, Acr(aEuro cent)-Mes(aEuro cent+). The Mes(aEuro cent+) moiety can oxidize chloride ion (Cl-) by electron transfer to produce chlorine radical (Cl-aEuro cent), whereas the Acr(aEuro cent) moiety can reduce O-2 to O (2) (aEuro cent a') . The Cl-aEuro cent radical produced abstracts a hydrogen from toluene to afford benzyl radical in competition with the bimolecular radical coupling of Cl-aEuro cent. The benzyl radical reacts with O-2 rapidly to afford the peroxyl radical, leading to the oxygenated product, benzaldehyde. Benzaldehyde is readily further photooxygenated to yield benzoic acid with Acr(aEuro cent)-Mes(aEuro cent+). In the case of an aromatic compound with electron-donating substituents, 1,3,5-trimethoxybenzene, photocatalytic chlorination occurred efficiently under the same photoirradiation conditions to yield a monochloro-substituted compound, 2,4,6-trimethoxychlorobenzene.

Abstract  INTRODUCTION: Systemic sclerosis (SSc) has complex pathogenesis and likely multifactorial causes. Environmental exposures have been suggested to play a role in SSc pathogenesis, including occupational exposure to pollutants and chemicals as well as use of drugs leading to modulation of immune response. Thus, this case-control study aimed to assess: the relationship between SSc and occupational exposure; and the risk of SSc related to occupational exposure in male and female patients.

METHODS: From 2005 to 2008, 100 patients with a definite diagnosis of SSc were included in the study; 3 age, gender, and smoking habits matched controls were selected for each patient. A committee of experts evaluated blindly occupational exposure to crystalline silica, white spirit, organic solvents, ketones, welding fumes, epoxy resins, and pesticides; an occupational exposure score was calculated for all subjects. Our findings were compared with previous data in the literature.

RESULTS: Increased ORs for SSc were found for: crystalline silica (p<0.0001), white spirit (p<0.0001), aromatic solvents (p=0.0002), chlorinated solvents (p=0.014), trichlorethylene (p=0.044), ketones (p=0.002) and welding fumes (p=0.021). Elevated risk associated with high final cumulative score in SSc was observed for: crystalline silica, white spirit, chlorinated solvents, trichlorethylene, aromatic solvents, any type of solvents, ketones and welding fumes. A marked association between SSc and occupational exposure was further found for: 1) crystalline silica, chlorinated solvents, trichloroethylene, white spirit, ketones and welding fumes in male patients; and 2) white spirit, aromatic solvents, any type of solvent and ketones in female patients. Finally, we did not find an association between SSc and: 1) the use of drugs that have been speculated to play a role in SSc onset (anorexigens, pentazocine, bromocriptine, l-tryptophan); 2) implants - that are prosthesis, silicone implants, and contact lenses; and 3) dyeing hair. In the literature, SSc has been associated with occupational exposure to silica and solvents, while the association between SSc and specific organic solvents and welding fumes has been anecdotally reported.

CONCLUSION: The following occupational factors have an impact in the development of SSc: crystalline silica, white spirit, aromatic solvents, chlorinated solvents, trichlorethylene, ketones and welding fumes. The risk of SSc appears to be markedly associated with high cumulative exposure. Finally, the association between SSc and occupational exposure may be variable according to gender.

Abstract  The reaction of three types of carbon nanofibers (CNFs; platelet: CNF-P, tubular: CNF-T, herringbone: CNF-H) with Ir4(CO)12 in mesitylene at 165 °C provided the corresponding CNF-supported iridium nanoparticles, Ir/CNFs (Ir content=2.3-2.6 wt.%). Transmission electron microscopy (TEM) studies of these Ir/CNF samples revealed that size-controlled Ir nanoparticles (average particle size of 1.1-1.5 nm) existed on the CNFs. Among the three Ir/CNF samples, Ir/CNF-T showed an excellent catalytic activity and chemoselectivity towards hydrogenation of functionalized nitroarenes and imines; the corresponding aniline derivatives were obtained with high turnover numbers at ambient temperature under 10 tm of H2 , and the catalyst is reusable. Ir/CNF-T was also effective for the reductive N-alkylation of anilines with carbonyl compounds.

Abstract  Desilication method has been developed to prepare hierarchical zeolites. However, the hierarchical Beta prepared by desilication generally exhibited much poorer catalytic activity than parent one in some acidcatalyzed reactions mainly due to the great loss of acidity. Here, we report that subsequent acid treatment after desilication can greatly recover the acidity of zeolite Beta. As a result, the hierarchical Beta with acid treatment exhibited enhanced catalytic performance in the benzylation of benzene or mesitylene with relatively large molecular size. Additionally, the local structural change in zeolite Beta before and after post treatment was deeply studied by the NMR technique. The results indicated that during the desilication partial tetrahedral coordination Al was transformed into the distorted tetrahedral and pentahedral coordination Al and subsequent acid treatment led to the increase of the proportion of tetrahedral coordination Al. Thus, the number of total Bronsted acid sites in zeolite Beta was decreased after the desilication and subsequent acid treatment may increase the number of total and accessible Bronsted acid sites. These results suggested that acid treatment is helpful for improving the catalytic performance of the desilicated Beta in some acid-catalytic reactions, especially toward large molecules. (C) 2014 Elsevier Inc. All rights reserved.