Adjusting Ortho-Cycloalkyl Ring Size in a Cycloheptyl-Fused N,N,N-Iron Catalyst as Means to Control Catalytic Activity and Polyethylene Properties

Five examples of bis(arylimino)tetrahydrocyclohepta[b]pyridine dichloroiron(II) complex, [2-{(Ar)N=CMe}-9-{N(Ar)}C10H10N]FeCl2 (Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2Fe1, 2-(C6H11)-4,6-(CHPh2)2C6H2Fe2, 2-(C8H15)-4,6-(CHPh2)2C6H2Fe3, 2-(C12H23)-4,6-(CHPh2)2C6H2Fe4, and 2,6-(C5H9)2-4-(CHPh2)C6H2Fe5), incorporating ortho-pairings based on either benzhydryl/cycloalkyl (ring sizes ranging from 5 to 12) or cyclopentyl/cyclopentyl groups, have been prepared in reasonable yield by employing a simple one-pot template strategy. Each complex was characterized by FT-IR spectroscopy, elemental analysis, and for Fe3 and Fe5 by single crystal X-ray diffraction; pseudo-square pyramidal geometries are a feature of their coordination spheres. On treatment of Fe1–Fe5 with modified methylaluminoxane (MMAO) or methylaluminoxane (MAO), a range in catalytic activities for ethylene polymerization were observed with benzhydryl/cyclopentyl-containing Fe1/MMAO achieving the maximum level of 15.3 × 106 g PE mol−1 (Fe) h−1 at an operating temperature of 70 °C. As a key trend, the activity was found to drop as the ortho-cycloalkyl ring size increased: Fe1C5H9/CHPh2~Fe5C5H9/C5H9 > Fe2C6H11/CHPh2 > Fe3C8H15/CHPh2 > Fe4C12H23/CHPh2. Furthermore, strictly linear polyethylenes (Tm > 126 °C) were formed with molecular weights again dependent on the ortho-cycloalkyl ring size (up to 55.6 kg mol−1 for Fe1/MAO); narrow dispersities were a characteristic of all the polymers (Mw/Mn range: 2.3–4.7), highlighting the well-controlled nature of these polymerizations.

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Fusing Carbocycles of Inequivalent Ring Size to a Bis(imino)pyridine-Iron Ethylene Polymerization Catalyst: Distinctive Effects on Activity, PE Molecular Weight, and Dispersity

Research ◽

10.34133/2019/9426063 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15 ◽

Cited By ~ 4

Author(s):

Zheng Wang ◽

Gregory A. Solan ◽

Yanping Ma ◽

Qingbin Liu ◽

Tongling Liang ◽

...

Keyword(s):

Molecular Weight ◽

Ethylene Polymerization ◽

Bimodal Distribution ◽

X Ray Diffraction ◽

One Pot ◽

Molecular Weights ◽

Pyramidal Geometry ◽

Wide Range ◽

Saturated Chain ◽

Ft Ir

The 4,6-bis(arylimino)-1,2,3,7,8,9,10-heptahydrocyclohepta[b]quinoline-iron(II) chlorides (aryl = 2,6-Me2C6H3Fe1; 2,6-Et2C6H3Fe2; 2,6-i-Pr2C6H3Fe3; 2,4,6-Me3C6H2Fe4; and 2,6-Et2-4-Me2C6H2Fe5) have been prepared in good yield by a straightforward one-pot reaction of 2,3,7,8,9,10-hexahydro-1H-cyclohepta[b]quinoline-4,6-dione, FeCl2·4H2O, and the appropriate aniline in acetic acid. All ferrous complexes have been characterized by elemental analysis and FT-IR spectroscopy. In addition, the structure of Fe3 has been determined by single crystal X-ray diffraction, which showed the iron center to adopt a distorted square pyramidal geometry with the saturated sections of the fused six- and seven-membered carbocycles to be cis-configured. In combination with either MAO or MMAO, Fe1–Fe5 exhibited exceptionally high activities for ethylene polymerization (up to 15.86×106 gPE mol−1 Fe h−1 at 40°C (MMAO) and 9.60×106 gPE mol−1 Fe h−1 at 60°C (MAO)) and produced highly linear polyethylene (HLPE, Tm≥128°C) with a wide range in molecular weights; in general, the MMAO-promoted polymerizations were more active. Irrespective of the cocatalyst employed, the 2,6-Me2-substituted Fe1 and Fe4 proved the most active while the more sterically hindered 2,6-i-Pr2Fe3 the least but afforded the highest molecular weight polyethylene (Mw: 65.6–72.6 kg mol-1). Multinuclear NMR spectroscopic analysis of the polymer formed using Fe4/MMAO at 40°C showed a preference for fully saturated chain ends with a broad bimodal distribution a feature of the GPC trace (Mw/Mn=13.4). By contrast, using Fe4/MAO at 60°C a vinyl-terminated polymer of lower molecular weight (Mw=14.2 kg mol−1) was identified that exhibited a unimodal distribution (Mw/Mn=3.8). Moreover, the amount of aluminoxane cocatalyst employed, temperature, and run time were also found to be influential on the modality of the polymer.

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One-pot multicomponent synthesis of furo[3,2-c]coumarins promoted by amino-functionalized Fe3O4@SiO2 nanoparticles

Zeitschrift für Naturforschung B ◽

10.1515/znb-2016-0041 ◽

2016 ◽

Vol 71 (8) ◽

pp. 849-856 ◽

Cited By ~ 10

Author(s):

Javad Safaei-Ghomi ◽

Hossein Shahbazi-Alavi ◽

Pouria Babaei

Keyword(s):

Sio2 Nanoparticles ◽

Environmentally Benign ◽

Biological Applications ◽

X Ray Diffraction ◽

Multicomponent Synthesis ◽

One Pot ◽

Diversity Oriented Synthesis ◽

X Ray ◽

Ft Ir ◽

Ft Ir Spectroscopy

AbstractAmino-functionalized Fe3O4@SiO2 nanoparticles (Fe3O4@SiO2–NH2 NPs) were prepared by treating Fe3O4@SiO2 NPs with (3-aminopropyl)-triethoxysilane. They have been characterized by powder X-ray diffraction, vibrating sample magnetometer, scanning electronic microscopy, energy dispersive X-ray, thermogravimetric analysis and FT-IR spectroscopy. A neat, atom-economical, environmentally benign one-pot multicomponent synthetic route for the synthesis of furo[3,2-c]coumarins in good yields has been devised using the Fe3O4@SiO2–NH2 NPs. The present methodology can be used for the design of libraries and diversity-oriented synthesis, and has potential for biological applications and drug discovery.

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A New FeIII Substituted Arsenotungstate [FeIII2(AsIIIW6O23)2(AsIIIO3H)2]12−: Synthesis, Structure, Characterization and Magnetic Properties

Magnetochemistry ◽

10.3390/magnetochemistry6040054 ◽

2020 ◽

Vol 6 (4) ◽

pp. 54

Author(s):

Masooma Ibrahim ◽

Yan Peng ◽

Christopher E. Anson

Keyword(s):

Magnetic Properties ◽

Fourier Transform ◽

Structure Characterization ◽

Basic Medium ◽

Antiferromagnetic Coupling ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Ft Ir ◽

Ft Ir Spectroscopy

The iron(III)-containing arsenotungstate [FeIII2(AsIIIW6O23)2(AsIIIO3H)2]12− (1) was prepared via a simple, one-pot reaction in aqueous basic medium. The compound was isolated as its sodium salt, and structurally-characterized by Single Crystal X-ray Diffraction (SCXRD), Powder X-ray Diffraction (PXRD), Fourier-Transform Infrared (FT-IR) spectroscopy, Thermogravimetric Analysis (TGA) and elemental analysis. Its magnetic properties are reported; the antiferromagnetic coupling between the two FeIII centers is unusually weak as a result of the bridging geometry imposed by the rigid arsenotungstate metalloligands.

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Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽

10.3390/ma14071786 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1786

Author(s):

Carla Queirós ◽

Chen Sun ◽

Ana M. G. Silva ◽

Baltazar de Castro ◽

Juan Cabanillas-Gonzalez ◽

...

Keyword(s):

Water Content ◽

Coordination Polymers ◽

Metal Ion ◽

Low Cost ◽

Microwave Assisted Synthesis ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Ft Ir ◽

Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

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Hydrothermal synthesis, crystal structure and properties of a two-dimensional uranyl coordination polymer based on a flexible zwitterionic ligand

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229618002279 ◽

2018 ◽

Vol 74 (3) ◽

pp. 366-371 ◽

Cited By ~ 1

Author(s):

Wen Cui ◽

Ruyu Wang ◽

Xi Shu ◽

Yu Fan ◽

Yang Liu ◽

...

Keyword(s):

Coordination Polymer ◽

Hydrothermal Reaction ◽

Two Dimensional ◽

X Ray Diffraction ◽

Uranyl Compounds ◽

X Ray ◽

Potential Applications ◽

Ft Ir ◽

Fuel Reprocessing ◽

Ft Ir Spectroscopy

The interaction between the uranyl cation, (UO2)2+, and organic species is of interest due to the potential applications of the resulting compounds with regard to nuclear waste disposal and nuclear fuel reprocessing. The hydrothermal reaction of various uranyl compounds with flexible zwitterionic 1,1′-[1,4-phenylenebis(methylene)]bis(pyridin-1-ium-4-carboxylate) dihydrochloride (Bpmb·2HCl) in deionized water containing drops of H2SO4resulted in the formation of a novel two-dimensional uranyl coordination polymer, namely poly[tetraoxido{μ2-1,1′-[1,4-phenylenebis(methylene)]bis(pyridin-1-ium-4-carboxylate)}di-μ3-sulfato-diuranium(VI)], [(UO2)2(SO4)2(C20H16N2O4)]n, (1). Single-crystal X-ray diffraction reveals that this coordination polymer exhibits a layered arrangement and the (UO2)2+centre is coordinated by five equatorial O atoms. The structure was further characterized by FT–IR spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The polymer shows high thermal stability up to 696 K. Furthermore, the photoluminescence properties of (1) has also been studied, showing it to exhibit a typical uranyl fluorescence.

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Study on Nano- and Microcrystallites in Urines of Uric Acid Stone Patients

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.655-657.1927 ◽

2013 ◽

Vol 655-657 ◽

pp. 1927-1930 ◽

Cited By ~ 1

Author(s):

Guang Na Zhang ◽

Zhi Yue Xia ◽

Jian Ming Ouyang ◽

Li Kuan

Keyword(s):

Electron Microscopy ◽

Uric Acid ◽

X Ray Diffraction ◽

Uric Acid Stone ◽

Urine Ph ◽

Stone Formers ◽

Transmission Electron ◽

Close Relationship ◽

Ft Ir ◽

Ft Ir Spectroscopy

The presence of crystallites in urine is closely related to stones formation. In this article, the components, morphology of nano- and micro-crystallites in urines of 20 uric acid (UA) stone formers as well as their relationship with the formation of UAstones were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The main constituent of urinary crystallites was uric acid. Their particle size distribution was highly uneven, ranging from several nanometers to several tens of micrometers, and obvious aggregation was observed. These results showed that there was close relationship among stone components, urinary crystallites composition and urine pH.

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Preparation and Characterization of Cefradine/Montmorillionite Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.560-561.434 ◽

2012 ◽

Vol 560-561 ◽

pp. 434-437 ◽

Cited By ~ 1

Author(s):

Lan Wang ◽

Wen Ji Guo ◽

Yan Zhao Zhao

Keyword(s):

Gastric Fluid ◽

Simulated Gastric Fluid ◽

X Ray Diffraction ◽

Simulated Intestinal Fluid ◽

Solution Intercalation ◽

Method Of Solution ◽

Ft Ir ◽

In The Beginning ◽

Ft Ir Spectroscopy

The objective of this paper was to prepare the composite of crefradine/montmorillionite in the method of solution intercalation. The drug load and intercalation rate varied with the drug concentration. X-ray diffraction (XRD), Fourier transformed infrared (FT-IR) Spectroscopy, and thermal analysis (TG-DSC) were applied to characterize composite mentioned above. Together with drug release tests, results indicate cefradine intercalated into montmorillionite.The release profiles of cefradine/MMT in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.4) at 37°Cduring 10h are shown in Fig. 4. The amount of cefradine in the beginning 2h came up to 35% and 50%, and in the following time, cefradine released slowly. The release behaviors met the requirements of sustained release.

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Synthesis of new bimetallic phosphate (Al/Ag3PO4) and study for its Catalytic performance in the synthesis of 1,2-dihydro-l-phenyl-3H-naphth [1,2-e]-[1,3] oxazin-3-one derivatives

Mediterranean Journal of Chemistry ◽

10.13171/mjc02108091579elhallaoui ◽

2021 ◽

Vol 11 (3) ◽

pp. 215

Author(s):

Achraf El Hallaoui ◽

Tourya Ghailane ◽

Soukaina Chehab ◽

Youssef Merroun ◽

Rachida Ghailane ◽

...

Keyword(s):

Reaction Times ◽

Catalytic Performance ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Silver Sulfate ◽

Triple Super Phosphate ◽

Aryl Aldehyde ◽

Ft Ir ◽

First Time

This work aims to prepare a new bimetallic phosphate catalyst using a new simple and effective method. This new catalyst was ready for the first time by a modification of Triple Super Phosphate (TSP) fertilizer with silver sulfate (AgSO4), followed by the impregnation of the aluminum atoms using aluminum nitrate (Al(NO3)3). The use of Al/Ag3PO4, for the first time as a heterogeneous catalyst in organic chemistry, offers a new, efficient, and green pathway for synthesizing 1,2-dihydro-l-phenyl-3H-naphth[1,2-e]-[1,3]oxazin-3-one derivatives by one-pot three-component cyclocondensation of b-naphthol, aryl aldehyde, and urea. The structure and the morphology of the prepared catalyst were characterized by spectroscopic methods such as X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), and dispersive X-ray spectrometry coupled with a scanning electron microscope (EDX-SEM). In addition, the optimization of the reaction parameters was carried out considering the effect of catalyst amount, the temperature, and the solvent. The procedure described herein allowed a comfortable preparation of oxazine derivatives with excellent yields, short reaction times, and in the absence of organic solvent.

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The Bio-fabrication of Gold Nanoparticles (AuNPs) by Green Method and Study of its Electrochemical Applications

Brilliant Engineering ◽

10.36937/ben.2020.004.004 ◽

2020 ◽

Vol 1 (4) ◽

pp. 22-25

Author(s):

Azwan Morni

Keyword(s):

Gold Nanoparticles ◽

Ir Spectroscopy ◽

Face Centered Cubic ◽

X Ray Diffraction ◽

Green Method ◽

Oh Groups ◽

X Ray ◽

Vis Spectroscopy ◽

Ft Ir ◽

Ft Ir Spectroscopy

This study reports a green method for the synthesis of gold nanoparticles (AuNPs) using the aqueous extract of Salix aegyptiaca extract. The effects of gold salt concentration, extract concentration and extract quantity were investigated on nanoparticles synthesis. Novel methods of ideally synthesizing AuNPs are thus thought that are formed at ambient temperatures, neutral pH, low costs and environmentally friendly fashion. AuNPs were characterized with different techniques such as UV–vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and TEM. FT-IR spectroscopy revealed that gold nanoparticles were functionalized with biomolecules that have primary carbonyl group, -OH groups and other stabilizing functional groups. TEM experiments showed that these nanoparticles are formed with various shapes and X-ray diffraction pattern showed high purity and face centered cubic structure of AuNPs. For electrochemical properties of AuNPs, a modified glassy carbon electrode using AuNPs (AuNPs/GCE) was investigated. The results show that electronic transmission rate between the modified electrode and [Fe (CN)6]3-/4- increased.

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