Unifying Molecular Weights of Highly Linear Polyethylene Waxes through Unsymmetrical 2,4-Bis(imino)pyridylchromium Chlorides

By dealing CrCl3∙3THF with the corresponding ligands (L1–L5), an array of fluoro-substituted chromium (III) chlorides (Cr1–Cr5) bearing 2-[1-(2,4-dibenzhydryl-6-fluoro- phenylimino)ethyl]-6-[1-(arylimino)ethyl]pyridine (aryl = 2,6-Me2Ph Cr1, 2,6-Et2Ph Cr2, 2,6-iPr2Ph Cr3, 2,4,6-Me3Ph Cr4, 2,6-Et2-4-MePh Cr5) was synthesized in good yield and validated via Fourier Transform Infrared (FT-IR) spectroscopy and elemental analysis. Besides the routine characterizations, the single-crystal X-ray diffraction study revealed the solid-state structures of complexes Cr2 and Cr4 as the distorted-octahedral geometry around the chromium center. Activated by either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), all the chromium catalysts exhibited high activities toward ethylene polymerization with the MMAO-promoted polymerizations far more productive than with MAO (20.14 × 106 g (PE) mol−1 (Cr) h−1 vs. 10.03 × 106 g (PE) mol−1 (Cr) h−1). In both cases, the resultant polyethylenes were found as highly linear polyethylene waxes with low molecular weights around 1–2 kg mol−1 and narrow molecular weight distribution (MWD range: 1.68–2.25). In general, both the catalytic performance of the ortho-fluorinated chromium complexes and polymer properties have been the subject of a detailed investigation and proved to be highly dependent on the polymerization reaction parameters (including cocatalyst type and amount, reaction temperature, ethylene pressure and run time).

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Structural, Non-Covalent Interaction, and Natural Bond Orbital Studies on Bromido-Tricarbonyl Rhenium(I) Complexes Bearing Alkyl-Substituted 1,4-Diazabutadiene (DAB) Ligands

Crystals ◽

10.3390/cryst10040267 ◽

2020 ◽

Vol 10 (4) ◽

pp. 267 ◽

Cited By ~ 2

Author(s):

Reza Kia ◽

Azadeh Kalaghchi

Keyword(s):

Density Functional ◽

Natural Bond Orbital ◽

Carbonyl Groups ◽

X Ray Diffraction ◽

Functional Theory ◽

Covalent Interaction ◽

Distorted Octahedral ◽

Elemental Analyses ◽

Ft Ir ◽

Solid State Structures

The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene, 2,4-Me2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene, 2,4-Me2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene, 2,4,6-Me3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene, 2,6-ipr2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR, 1H-NMR, 13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each complex, the Re(I) centre shows a distorted octahedral shape with a facial geometry of carbonyl groups. The gas phase geometry of the complexes was identified by density functional theory. Interesting intermolecular n…π* interactions of complexes 1 and 3 were investigated by non-covalent interaction index (NCI), and natural bond orbital (NBO) analyses. The intramolecular n…σ*, σ…π*, π…σ* interactions were also studied in complexes 3 and 4.

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Reaction of 2-[(2-aminoethyl)amino]ethanol with pyridine-2-carbaldehyde and complexation of the products with CuII and CdII along with docking studies

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619008258 ◽

2019 ◽

Vol 75 (7) ◽

pp. 951-959 ◽

Cited By ~ 1

Author(s):

Zahra Mardani ◽

Mohammad Hakimi ◽

Keyvan Moeini ◽

Fabian Mohr

Keyword(s):

Crystal Packing ◽

Docking Studies ◽

Molar Ratio ◽

Distorted Octahedral Geometry ◽

X Ray Diffraction ◽

Donor Ligand ◽

X Ray ◽

H Nmr ◽

Distorted Octahedral ◽

Ft Ir

The reaction between 2-[2-(aminoethyl)amino]ethanol and pyridine-2-carbaldehyde in a 1:2 molar ratio affords a mixture containing 2-({2-[(pyridin-2-ylmethylidene)amino]ethyl}amino)ethanol (PMAE) and 2-[2-(pyridin-2-yl)oxazolidin-3-yl]-N-(pyridin-2-ylmethylidene)ethanamine (POPME). Treatment of this mixture with copper(II) chloride or cadmium(II) chloride gave trichlorido[(2-hydroxyethyl)({2-[(pyridin-2-ylmethylidene)amino]ethyl})azanium]copper(II) monohydrate, [Cu(C10H16N3O)Cl3]·H2O or [Cu(HPMAE)Cl3]·H2O, 1, and dichlorido{2-[2-(pyridin-2-yl)oxazolidin-3-yl]-N-(pyridin-2-ylmethylidene)ethanamine}cadmium(II), [CdCl2(C16H18N4O)] or [CdCl2(POPME)], 2, which were characterized by elemental analysis, FT–IR, Raman and 1H NMR spectroscopy and single-crystal X-ray diffraction. PMAE is potentially a tetradentate N3O-donor ligand but coordinates to copper here as an N2 donor. In the structure of 1, the geometry around the Cu atom is distorted square pyramidal. In 2, the Cd atom has a distorted octahedral geometry. In addition to the hydrogen bonds, there are π–π stacking interactions between the pyridine rings in the crystal packing of 1 and 2. The ability of PMAE, POPME and 1 to interact with ten selected biomolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS, Top II and B-DNA) was investigated by docking studies and compared with doxorubicin.

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Synthesis, Structure and Antioxidant Activity of Mixed Ruthenium(III) Benzoyl Pyridine Complex

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22349 ◽

2020 ◽

Vol 32 (3) ◽

pp. 641-645

Author(s):

E. Jayanthi ◽

M. Anusuya ◽

R. Anusuya ◽

K. Thenmozhi ◽

A. Nagaveni ◽

...

Keyword(s):

Antioxidant Activity ◽

Carbonyl Oxygen ◽

Distorted Octahedral Geometry ◽

Significant Activity ◽

X Ray Diffraction ◽

X Ray ◽

Pyridine Complex ◽

Pyridine Nitrogen ◽

Distorted Octahedral ◽

Ft Ir

A new ruthenium arsine complex was prepared by reacting equimolar ratio of [RuBr3(AsPh3)3] and 2-benzoyl pyridine. It was characterized by microanalysis, FT-IR and single crystal X-ray diffraction studies. X-ray diffraction data showed the distorted octahedral geometry of the complex. The pyridine nitrogen and carbonyl oxygen of the ligand coordinated with the metal center. Antioxidant activity of the complex was analyzed using different assays, which manifested significant activity. It has been found that a newly synthesized complex possessed better antioxidant activity than the ligand and precursor complex.

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Complexation to Cadmium(II) of a Tetradentate Ligand Resulting from the Condensation of 2-Pyridinecarbaldehyde with N-(2- Aminoethyl)propane-1,3-diamine

Zeitschrift für Naturforschung B ◽

10.5560/znb.2013-2294 ◽

2013 ◽

Vol 68 (3) ◽

pp. 267-271 ◽

Cited By ~ 18

Author(s):

Mohammad Hakimi ◽

Zahra Mardani ◽

Keyvan Moeini ◽

Esther Schuh ◽

Fabian Mohr

Keyword(s):

Crystal Structure ◽

Molar Ratio ◽

Distorted Octahedral Geometry ◽

X Ray Diffraction ◽

Iodide Ions ◽

H Nmr ◽

Distorted Octahedral ◽

Elemental Analyses ◽

Ft Ir ◽

Nmr Signals

The reaction of 2-pyridinecarbaldehyde with N-(2-aminoethyl)propane-1,3-diamine in a 2 : 1 molar ratio under microwave irradiation gave 2-(2-(pyridin-2-yl)-tetrahydropyrimidin-1(2H)-yl)-N- (pyridin-2-ylmethylene)ethanamine (L) as a mixture with the isomer 3-(2-(pyridin-2-yl)imidazolidin- 1-yl)-N-(pyridin-2-ylmethylene)propan-1-amine (L*). The molecules were characterized by elemental analyses and spectroscopic methods. Percentages of L and L* were evaluated through integration of selected 1H NMR signals. The cadmium iodide complex of L, [Cd(L)I2]·H2O (1), was prepared and identified by elemental analysis, FT-IR, Raman, and 1H NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal structure of 1 the cadmium atom with four coordinated nitrogen atoms and two iodide ions has a distorted octahedral geometry. A water molecule is also incorporated in the crystal network. Several hydrogen bonds including N-H···O, C-H···O, C-H···I, and O-H···I interactions are present in the crystal structure of 1.

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Liquid crystalline polyureas with oligo(ethylene glycol) sequences

e-Polymers ◽

10.1515/epoly.2010.10.1.1425 ◽

2010 ◽

Vol 10 (1) ◽

Author(s):

Shahram Mehdipour-Ataei ◽

Leila Akbarian-Feizi

Keyword(s):

Liquid Crystalline ◽

Spectroscopic Method ◽

Polymerization Reaction ◽

X Ray Diffraction ◽

Subsequent Reaction ◽

Scanning Calorimetry ◽

Polar Solvents ◽

X Ray ◽

H Nmr ◽

Ft Ir

AbstractA diamine monomer containing ester, amide and ether functional groups was prepared and its polymerization reaction with different diisocyanates to give main chain poly(ester amide ether urea)s was investigated. The monomer was synthesized via reaction of terephthaloyl chloride with 4-hydroxybenzoic acid and subsequent reaction of the resulted diacid with 1,8-diamino-3,6-dioxaoctane. The polymers were characterized by FT-IR and 1H-NMR spectroscopic method and elemental analysis. The resulting polymers exhibited excellent solubility in polar solvents. Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited semi-crystalline patterns. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were in the range of 88-112 °C. The temperatures for 10% weight loss (T10) from their thermogravimetric analysis (TGA) curves were found to be in the range of 297-312 °C in air. Also the prepared polyureas showed liquid crystalline character.

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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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Some Novel Manganese(III) Mixed Ligand Complexes and its Decolourization Studies

Oriental Journal Of Chemistry ◽

10.13005/ojc/340625 ◽

2018 ◽

Vol 34 (6) ◽

pp. 2867-2871

Author(s):

Deepika Jaiswal ◽

Sudha Yadava

Keyword(s):

Mass Spectrometry ◽

Mixed Ligand ◽

Mixed Ligand Complexes ◽

Distorted Octahedral Geometry ◽

Ligand Field ◽

Distorted Octahedral ◽

Ft Ir ◽

Ethylenediamine Ligand ◽

Red Dye ◽

Ligand Field Parameters

Some novel mixed ligand complexes of Mn(III) with glycine ligand namely [Mn(gly)2 Cl(en)], [Mn(gly)2 Br(en)], [Mn(gly)2 N3 (en)] and [Mn(gly)2 NCS(en)] have been synthesized starting from Mn(gly)2 Cl, Mn(gly)2 Br, Mn(gly)2N3 and Mn(gly)2 NCS respectively. These newly synthesized complexes have been characterized by UV/Vis, FT-IR and Mass spectrometry. The spectroscopic data suggest distorted octahedral geometry for all these mixed ligand complexes. The λmax values of these complexes for 5T2g → 5Eg transitions are 482 nm for [Mn(gly)2N3(en)], 488 for [Mn(gly)2NCS(en)], 486 for [Mn(gly)2 Br(en)] and 484 for [Mn(gly)2Cl(en)], all these transitions are red shifted in comparison to their parent complexes. The ligand field parameters such as 10 Dq, B and β have also been calculated and suggest covalent metal ligand bonding. One peculiar finding is that the FT-IR spectra shows frequencies for both free and coordinated NH2 group in all complexes indicating that the ethylenediamine ligand present here is non bridging in nature. The mass spectrometry results show molecular ion peaks at m/z 300, 345, 307 and 323 for [Mn(gly)2Cl(en)], [Mn(gly)2Br(en)], [Mn(gly)2N3(en)] and [Mn(gly)2NCS(en)] respectively. The coordination of ethylenediamine to Mn(III) enhances its efficiency towards decolourization methyl red dye.

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Fabrication of the Hierarchical HZSM-5 Membrane with Tunable Mesoporosity for Catalytic Cracking of n-Dodecane

Catalysts ◽

10.3390/catal9020155 ◽

2019 ◽

Vol 9 (2) ◽

pp. 155 ◽

Cited By ~ 8

Author(s):

Zhenheng Diao ◽

Lushi Cheng ◽

Xu Hou ◽

Di Rong ◽

Yanli Lu ◽

...

Keyword(s):

Catalytic Cracking ◽

Inductively Coupled Plasma ◽

Catalytic Performance ◽

X Ray Diffraction ◽

Inductively Coupled ◽

Swelling Agent ◽

Ft Ir ◽

Temperature Programmed ◽

Adsorption Desorption

Hierarchical HZSM-5 membranes were prepared on the inner wall of stainless steel tubes, using amphiphilic organosilane (TPOAC) and mesitylene (TMB) as a meso-porogen and a swelling agent, respectively. The mesoporosity of the HZSM-5 membranes were tailored via formulating the TPOAC/Tetraethylorthosilicate (TPOAC/TEOS) ratio and TMB/TPOAC ratio, in synthesis gel, and the prepared membranes were systematically characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), N2 adsorption–desorption, N2 permeation, inductively coupled plasma (ICP), in situ fourier transform infrared (FT-IR), ammonia temperature-programmed desorption (NH3-TPD), etc. It was found that the increase of the TPOAC/TEOS ratio promoted a specific surface area and diffusivity of the HZSM-5 membranes, as well as decreased acidity; the increase of the TMB/TPOAC ratios led to an enlargement of the mesopore size and diffusivity of the membranes, but with constant acid properties. The catalytic performance of the prepared HZSM-5 membranes was tested using the catalytic cracking of supercritical n-dodecane (500 °C, 4 MPa) as a model reaction. The hierarchical membrane with the TPOAC/TEOS ratio of 0.1 and TMB/TPOAC ratio of 2, exhibited superior catalytic performances with the highest activity of up to 13% improvement and the lowest deactivation rate (nearly a half), compared with the microporous HZSM-5 membrane, due to the benefits of suitable acidity, together with enhanced diffusivity of n-dodecane and cracking products.

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The Synthesis and Crystallization of Poly(vinylidene fluoride) in Supercritical CO2

e-Polymers ◽

10.1515/epoly.2006.6.1.979 ◽

2006 ◽

Vol 6 (1) ◽

Author(s):

Zhendong Shi ◽

Zhen Zheng ◽

Xiaoli Su ◽

Xinling Wang

Keyword(s):

Vinylidene Fluoride ◽

Degree Of Crystallinity ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Molecular Weights ◽

Good Solubility ◽

Poly Vinylidene Fluoride ◽

Ft Ir ◽

Application Fields ◽

Crystallization Mode

AbstractA series of poly(vinylidene fluoride)s (PVDFs) is synthesized in supercritical carbon dioxide (sc-CO2). The influences of polymerization pressure, molecular weight distribution and H-H defect concentration on the crystallization of PVDF have been studied in combination with differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXRD) and Fourier transform infrared spectroscopy (FT-IR) measurements. The result shows that the morphology, molecular weights, polydispersity and head-to-head (H-H) defect concentrations of the PVDFs are affected by the reaction pressure and good solubility generated from sc-CO2. Especially, the sc-CO2 polymerization has greatly improved the crystallization mode of the obtained PVDFs such as the complete degree of crystallinity, crystallinity and the crystal phase. This will create more comprehensive application fields for PVDF.

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Synthesis, Characterization, and Ethylene Oligomerization and Polymerization by 2-Quinoxalinyl-6-iminopyridine Chromium Chlorides

Australian Journal of Chemistry ◽

10.1071/ch08016 ◽

2008 ◽

Vol 61 (5) ◽

pp. 397 ◽

Cited By ~ 21

Author(s):

Saliu A. Amolegbe ◽

Maliha Asma ◽

Min Zhang ◽

Gang Li ◽

Wen-Hua Sun

Keyword(s):

High Selectivity ◽

Ethylene Oligomerization ◽

Distorted Octahedral Geometry ◽

Electronic Effects ◽

X Ray Diffraction ◽

Reaction Conditions ◽

Co Catalyst ◽

X Ray ◽

Catalytic Activities ◽

Distorted Octahedral

A series of chromium(iii) complexes ligated by N^N^N tridentate 2-quinoxalinyl-6-iminopyridine were synthesized and characterized by elemental analysis and infrared spectroscopy. Single-crystal X-ray diffraction analysis for the structure of complex C3 reveals a distorted octahedral geometry. When methylaluminoxane was employed as the co-catalyst, the chromium complexes showed high activities for ethylene oligomerization and polymerization. The distribution of oligomers obtained followed Schulz–Flory rules with high selectivity for α-olefins. Both steric and electronic effects of coordinated ligands affected the catalytic activities as well as the properties of the catalytic products. The parameters of the reaction conditions were also investigated to explore the optimum catalytic potentials of these complexes.

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