- Green reusable Pd nanoparticles embedded in phytochemical resins for mild hydrogenations of nitroarenes
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A green chemical preparation of Pd nanoparticles (NPs) embedded in phytochemical resins using a plant extract from Pulicaria odora L. and PdCl2 under ambiant conditions is reported. Two batches of Pd NPs have been prepared: they present homogeneous sizes of respectively 2.2 nm and 3.2 nm depending on the preparation conditions. The Pd NPs were characterized by different techniques (TEM, HRTEM, XRD, XPS and BET) and have been successfully used for the reduction of nitroarenes in EtOH under H2 at atmospheric pressure at rt in the presence of only 5 mequiv. of Pd. Finally the Pd NPs embedded in resin particles were easily recovered by filtration and used at least seven times without significant loss in efficiency. The residual amount of palladium found in the reaction product is very low (0.6% of the initial amount). Therefore both preparation of the Pd NPs and their use for hydrogenations of nitroarenes are environmentally benign.
- Enneiymy, Mohamed,Le Drian, Claude,Becht, Jean-Michel
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- Palladium nanoparticles embedded in mesoporous carbons as efficient, green and reusable catalysts for mild hydrogenations of nitroarenes
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The reduction of nitroarenes is the most efficient route for the preparation of aromatic primary amines. These reductions are generally performed in the presence of heterogeneous transition metal catalysts, which are rather efficient but long and tedious to prepare. In addition, they contain very expensive metals that are in most cases difficult to reuse. Therefore, the development of efficient, easily accessible and reusable Pd catalysts obtained rapidly from safe and non-toxic starting materials was implemented in this report. Two bottom-up synthesis methods were used, the first consisted in the impregnation of a micro/mesoporous carbon support with a Pd salt solution, followed by thermal reduction (at 300, 450 or 600 °C) while the second involved a direct synthesis based on the co-assembly and pyrolysis (600 °C) of a mixture of a phenolic precursor, glyoxal, a surfactant and a Pd salt. The obtained composites possess Pd nanoparticles (NPs) of tunable sizes (ranging from 1-2 to 7.0 nm) and homogeneously distributed in the carbon framework (pores/walls). It turned out that they were successfully used for mild and environment-friendly hydrogenations of nitroarenes at room temperature under H2(1 atm) in EtOH in the presence of only 5 mequiv. of supported Pd. The determinations of the optimal characteristics of the catalysts constituted a second objective of this study. It was found that the activity of the catalysts was strongly dependent on the Pd NPs sizes,i.e., catalysts bearing small Pd NPs (1.2 nm obtained at 300 °C and 3.4 nm obtained at 450 °C) exhibited an excellent activity, while those containing larger Pd NPs (6.4 nm and 7.0 nm obtained at 600 °C, either by indirect or direct methods) were not active. Moreover, the possibility to reuse the catalysts was shown to be dependent on the surface chemistry of the Pd NPs: the smallest Pd NPs are prone to oxidation by air and their surface was gradually covered by a PdO shell decreasing their activity during reuse. A good compromise between intrinsic catalytic activity (i.e. during first use) and possibility of reuse was found in the catalyst made by impregnation followed by reduction at 450 °C since the hydrogenation could be performed in only 2 h in EtOH or even in water. The catalyst was quantitatively recovered after reaction by filtration, used at least 7 times with no loss of efficiency. Advantageously, almost Pd-free primary aromatic amines were obtained since the Pd leaching was very low (0.1% of the introduced amount). Compared to numerous reports from the literature, the catalysts described here were both easily accessible from eco-friendly precursors and very active for hydrogenations under mild and “green” reaction conditions.
- Becht, Jean-Michel,Enneiymy, Mohamed,Fioux, Philippe,Le Drian, Claude,Matei Ghimbeu, Camelia
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- Defect Engineering into Metal-Organic Frameworks for the Rapid and Sequential Installation of Functionalities
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Postsynthetic treatments are well-known and important functionalization tools of metal-organic frameworks (MOFs). Herein, we have developed a practical and rapid postsynthetic ligand exchange (PSE) strategy using a defect-controlled MOF. An increase in the number of defects amounts to MOFs with enhanced rates of ligand exchange in a shorter time frame. An almost quantitative exchange was achieved by using the most defective MOFs. This PSE strategy is a straightforward method to introduce a functionality into MOFs including bulky or catalytically relevant moieties. Furthermore, some mechanistic insights into PSE were revealed, allowing for a sequential ligand exchange and the development of multifunctional MOFs with controlled ligand ratios.
- Park, Hyojin,Kim, Seongwoo,Jung, Byunghyuck,Park, Myung Hwan,Kim, Youngjo,Kim, Min
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- Selenium-catalyzed intramolecular atom- And redox-economical transformation ofo-nitrotoluenes into anthranilic acids
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Anthranilic acids (AAs) are significant basic chemicals used in pharmaceuticals, agrochemicals, dyes, fragrances,etc. Superfluous steps are always involved in obtaining AAs. Herein, we demonstrate a straightforward strategy to transform abundanto-nitrotoluenes into biologically and pharmaceutically significant AAs without any extra reductants, oxidants and protecting groups. Various sensitive groups, such as halogens, sulfide, aldehyde, pyridines, quinolines,etc., can be tolerated in this transformation. A hundred-gram-scale operation is realized efficiently with almost quantitative selenium recycling. Further mechanistic studies and DFT calculations disclosed the proposed atom-exchange processes and the key roles of the selenium species.
- Jiang, Xuefeng,Li, Yiming,Lin, Zhenyang,Wang, Yuhong,Yang, Tilong
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- Delivery of oxaliplatin to colorectal cancer cells by folate-targeted UiO-66-NH2
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Oxaliplatin is being used in different malignancies and several side effects are reported for patients taking Oxaliplatin, including peripheral neuropathy, nausea and vomiting, diarrhea, mouth sores, low blood counts, fatigue, loss of appetite, etc. Here we have developed a targeted anticancer drug delivery system based on folate-conjugated amine-functionalized UiO-66 for the delivery of oxaliplatin (OX). UiO-66-NH2 (U) and UiO-66-NH2–FA(FU) were pre-functionalized by the incorporation of folic acid (FA) into the structure via coordination of the carboxylate group of FA. The FTIR spectra of drug-loaded U and FU showed the presence of new carboxylic and aliphatic groups of OX and FA. Powder X-ray diffraction (PXRD) patterns were matched accordingly with the reference pattern and FESEM results showed semi-spherical particles (115–128 nm). The evaluated amounts of OX in U and FU were calculated 304.5 and 293 mg/g, respectively. The initial burst release of OX was 15.7% per hour for U(OX) and 10.8% per hour for FU(OX). The final release plateau gives 62.9% and 52.3% for U(OX) and FU(OX). To evaluate the application of the prepared delivery platform, they were tested on colorectal cancer cells (CT-26) via MTT assay, cell migration assay, and spheroid model. IC50 values obtained from MTT assay were 21.38, 95.50, and 18.20 μg/mL for OX, U(OX), and FU(OX), respectively. After three days of treatment, the CT26 spheroids at two doses of 500 and 50 μg/mL of U(OX) and FU(OX) showed volume reduction. Moreover, the oxidative behavior of the prepared systems within the cell was assessed by total thiol, malondialdehyde, and superoxide dismutase activity. The results showed that FU(OX) had higher efficacy in preventing the growth of CT-26 spheroid, and was more effective than oxaliplation in cell migration inhibition, and induced higher oxidative stress and apoptosis.
- Hashemzadeh, Alireza,Amerizadeh, Forouzan,Asgharzadeh, Fereshteh,Darroudi, Majid,Avan, Amir,Hassanian, Seyed Mahdi,Landarani, Mohammad,Khazaei, Majid
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- Anthranilic acid and derivatives thereof as well as synthesis method and application thereof
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In the reaction solvent, o-methyl (hetero) aryl nitro compound is taken as a reaction raw material and is used for water. The anthranilic acid and its derivatives are synthesized by the action of a catalyst, a base and an additive. The synthetic method has the advantages of cheap and easily available raw materials, simple reaction operation, high yield and excellent functional group tolerance, and provides a simple and efficient method for synthesizing o-aminobenzoic acid which is widely used in the aspects of dyes, medicines, pesticides, spices and the like. The invention further discloses the anthranilic acid and derivatives and application thereof, and has a wide application prospect.
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Paragraph 0104-0106
(2021/09/15)
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- Tuning the release rate of volatile molecules by pore surface engineering in metal-organic frameworks
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Encapsulation and controlled release of volatile molecules such as fragrances in a designed manner is important but challenging for the flavor and fragrance industry. Here, we report the tuning release of volatile molecules by postsynthetic modification of an amine-terminated metal-organic framework (MOF) MIL-101-NH2. By amidation, we obtained three MIL-101 MOFs, the trimethylacetamide-terminated TC-MIL-101, the benzamide-terminated BC-MIL-101, and the oxalic acid monoamide-terminated OC-MIL-101. All the MOFs can efficiently encapsulate volatile molecules. Moreover, we demonstrate that the release profile of volatiles can be widely tuned to sustain the release in several days to months and even over a year using different modified MIL-101 MOFs. We show that the release profiles are correlated with the binding energies between the guest volatiles and pores in MOFs. The pore diffusion and the synergistic transport are the rate-limiting step of the guest molecules from the modified MOFs.
- Chen, Hongwen,Chen, Huaqiang,Zhang, Bo,Jiang, Liming,Shen, Youqing,Fu, Engang,Zhao, Dan,Zhou, Zhuxian
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supporting information
p. 1988 - 1992
(2021/03/24)
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- IDENTIFICATION AND USE OF ERK5 INHIBITORS
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The present invention covers heterocyclic compounds of general formula (I) in which T, U, Y, Z, R1 and R3 are as defined herein, methods of preparing said compounds, intermediate compounds useful for preparing said compounds, pharmaceutical compositions and combinations comprising said compounds and the use of said compounds for manufacturing pharmaceutical compositions for the treatment or prophylaxis of diseases, in particular of cancer disorders, as a sole agent or in combination with other active ingredients.
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Page/Page column 71
(2019/10/01)
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- Mechanochemical catalytic transfer hydrogenation of aromatic nitro derivatives
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Mechanochemical ball milling catalytic transfer hydrogenation (CTH) of aromatic nitro compounds using readily available and cheap ammonium formate as the hydrogen source is demonstrated as a simple, facile and clean approach for the synthesis of substituted anilines and selected pharmaceutically relevant compounds. The scope of mechanochemical CTH is broad, as the reduction conditions tolerate various functionalities, for example nitro, amino, hydroxy, carbonyl, amide, urea, amino acid and heterocyclic. The presented methodology was also successfully integrated with other types of chemical reactions previously carried out mechanochemically, such as amide bond formation by coupling amines with acyl chlorides or anhydrides and click-type coupling reactions between amines and iso(thio)cyanates. In this way, we showed that active pharmaceutical ingredients Procainamide and Paracetamol could be synthesized from the respective nitro-precursors on milligram and gram scale in excellent isolated yields.
- Portada, Tomislav,Margeti?, Davor,?trukil, Vjekoslav
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supporting information
(2018/12/11)
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- B b for alcoholysis of polyethylene method of preparation of diazonium salt waste polyester
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The invention relates to a method for preparing diazonium salt by depolymerizing waste polyester through ethylene glycol. The method is characterized by comprising the following technical steps of (1) depolymerizing the waste polyester through the ethylene glycol to obtain a product BHET (terephthalate) or PTA (p-phthalic acid); (2) nitrifying and reducing the depolymerized product; (3) performing diazotization. According to the method, the BHET or PTA is obtained by depolymerizing the waste polyester through the ethylene glycol, and the diazonium salt can be prepared by nitrification, reduction, diazotization and the like; the diazonium salt can generate reaction with a series of coupling components to prepare azo dyes, so that the waste polyester can be effectively recycled and reused.
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Paragraph 0039
(2017/01/26)
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- Chemical recycling of waste poly(ethylene terephthalate) fibers into azo disperse dyestuffs
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In this study, waste poly(ethylene terephthalate) (PET) fibers were chemically recycled into azo disperse dyestuffs. First, waste PET fibers were glycolytically degraded by excess ethylene glycol utilizing zinc acetate dehydrate as a catalyst. The glycolysis product, bis(2-hydroxyethyl) terephthalate (BHET), was purified through recrystallization and hydrolyzed into terephthalic acid (TPA). Thereafter, BHET and TPA were nitrated, reduced and azotized to obtain diazonium salts. Finally, the obtained diazonium salts were coupled with N,N-dimethylaniline to obtain azo disperse dyestuffs (dye A and dye B, respectively). The depolymerized products (BHET and TPA) and azo disperse dyestuffs (dyes A and B) were characterized by FTIR and 1H NMR spectroscopy. Nylon and polyester filaments were dyed with the synthesized azo dyestuffs with the dye bath pH ranging from 3.6 to 5.8. The performances of the dyestuffs were described by maximum absorption wavelength, K/S, L, a and b values. This journal is
- Li, Mengjuan,Huang, Yanhong,Yu, Tianshi,Chen, Shiming,Ju, Anqi,Ge, Mingqiao
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p. 46476 - 46480
(2014/12/10)
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- Towards imaging electron density inside metal-organic framework structures
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Herein, we present electron density maps of three MOFs with different guests or post-synthetic modifications produced using single crystal X-ray data from laboratory diffractometers. Analysis of the electron density maps reveals possible differences insid
- Takashima, Yohei,Long, De-Liang,Cronin, Leroy
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supporting information
p. 2271 - 2274
(2014/03/21)
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- Chemoselective ligation of sulfinic acids with aryl-nitroso compounds
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Making a comeback: The inefficient condensation of sulfinic acid and aryl nitroso compounds has been transformed into a chemoselective process that converts sulfinic acid into stable cyclic sulfonamide analogues (see scheme). This ligation proceeds rapidly under aqueous conditions in high yield, and lays the groundwork for the development of sulfinic acid detection methods in biological systems. Copyright
- Lo Conte, Mauro,Carroll, Kate S.
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supporting information; scheme or table
p. 6502 - 6505
(2012/08/07)
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- BICYCLIC PYRIMIDINE DERIVATIVES AS CALCIUM CHANNEL BLOCKERS
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Methods and compounds effective in ameliorating conditions characterized by unwanted calcium channel activity, particularly unwanted T-type calcium channel activity are disclosed. Specifically, a series of compounds containing thienopyrimidine or oxoquinazoline derivatives are disclosed of the general formula (1) or formula (2) where X is a linker and Y is an aromatic moiety or N(R5)(R6).
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- Naaladase inhibitors for treating retinal disorders and glaucoma
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The present invention relates to pharmaceutical compositions and methods for treating a retinal disorder or glaucoma using NAALADase inhibitors.
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- Naaladase inhibitors for treating amyotrophic lateral sclerosis
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The present invention relates to pharmaceutical compositions and methods for treating amyotrophic lateral sclerosis using NAALADase inhibitors.
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- Benzenedicarboxylic acid derivatives
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New benzenedicarboxylic acid derivative compounds; pharmaceutical compositions, diagnostic methods, and diagnstic kits that include those compounds; and methods of using those compounds for inhibiting NAALADase enzyme activity, detecting diseases where NAALADase levels are altered, effecting neuronal activity, effecting TGF-β activity, inhibiting angiogenesis, and treating glutamate abnormalities, neutopathy, pain, compulsive disorders, prostate diseases, cancers, and glaucoma.
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- Disazo dyestuffs
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Disazo dyestuffs have been found which, in the form of the free acid, correspond to the formula (I) STR1 represents H or an optionally substituted aliphatic or aromatic radical and R1 to R6 and A have the meaning given in the description, which are outstandingly suitable for inkjet printing.
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- Synthesis and Electrochemistry of Pyrimidoquinazoline-5,10-diones. Design of Hydrolytically Stable High Potential Quinones and New Reductive Alkylation Systems
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The synthesis of pyrimidoquinazoline-5,10-diones 1 and pyrimidoquinazoline-5,10-diones 2 was carried out in conjunction with the design of both hydrolytically stable high potential quinones and new purine-like reductive alkylators.These systems consist of a benzoquinone ring bearing two fused pyrimidin-4(3H)-one rings.The fused pyrimidinone rings serve to protect 1 and 2 from hydrolysis as well as to raise quinone redox potentials by stabilizing the hydroquinones with internal hydrogen bonds (65 mV increase per hydrogen bond).Synthesis of 1 and 2 involved pyrimidinone ring annelation to a 2,5-diamino-3-nitroterephthalic acid derivative and to a 2,4-diamino-1,5-dicarboxy-3-nitrobenzene derivative, respectively.The synthetic studies provided insights into the electronic effects of nitro and amino groups on the annelation process.
- Skibo, Edward B.,Gilchrist, James H.
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p. 4209 - 4218
(2007/10/02)
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- Bisazo brown reactive dye
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A brown reactive dye represented by a free acid of the formula, STR1 wherein R is a hydrogen atom or a C1 to C4 alkyl group, X is --SO2 CH2 CH2 Cl, --SO2 CH=CH2, --SO2 CH2 CH2 OSO3 H or --SO2 CH2 CH2 OPO3 H2, rings A, B and C are each a benzene or naphthalene ring which may have other substituent, m is 0 to 3 and n is 0 to 1. This dye is suitable for dyeing cellulose fibers brown to afford dyeings superior in fastnesses, acid stability, build-up property and level dyeing property.
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- Pyrazoloquinazolin-9-ones: A New Series of Antiallergic Agents
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A new series of antiallergic agents, pyrazoloquinazolin-9-ones, was synthesized and evaluated for inhibitory effects in the rat reaginic passive cutaneous anaphylaxis (PCA) screen.Several analogues were found to be more potent than cromolyn sodium intravenously.Structure-activity relationships are discussed.One of the compounds, 4,9-dihydro-5-methoxy-9-oxopyrazoloquinazoline-2-carboxylic acid (36), was found to be approximately 250 times more potent than cromolyn sodium intravenously.
- Sircar, Jagadish C.,Capiris, Thomas,Kesten, Stephen J.,Herzig, David J.
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p. 735 - 742
(2007/10/02)
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- Azo dyestuffs
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Azo dyestuffs, which in the acid form, are represented by the formula: wherein A is an aromatic radical, M is a 1,4-benzene radical which may be substituted, E is the residue of a coupling component which is free from azo groups, At least one of A and M containing a phosphonic acid group, and the metal complexes of those having a metallisable group are reactive dyes suitable for use in the process of German OLS No. 2324809.
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