Super Extended Calix[4]Pyrroles as Candidate for Binding Mercury

The binding of mercury Hg (II) by calix[4]pyrrole derivative; 2 has been much less discovered than anion complexation. The presence of hydroxyl group in the structure of meso-tetramethyl-tetrakis-[2(4-hydroxyphenyl)ethylcalix[4]pyrrole is important for further modifications in the next steps. The modification of the hydroxyl group by the substitution of ester group was carried out to produce the ester derivative for the modified calix[4]pyrrole 2. The ester group would be expected to deliver high electronic contributions in the complexation processes with the guests as well as to increase the solubility of the receptor in different organic solvents. 1H NMR and isothermal titration calorimetric studies revealed that the receptors exhibited strong interaction with mercury cation and the complexation process was driven enthalpically and entropically. Conductance measurements in acetonitrile were carried out to identify the composition of the formed complex. From Nano Isothermal Titration Calorimetric studies, the thermodynamic parameters for the complexation processes were calculated.

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Thermodynamic Parameters of Solutions of Sildenafil Citrate in Some Organic Solvents at Different Temperatures

Journal of Fundamental and Applied Sciences ◽

10.4314/jfas.v6i1.9 ◽

2015 ◽

Vol 6 (1) ◽

pp. 106 ◽

Cited By ~ 5

Author(s):

S Baluja ◽

K Bhesaniya

Keyword(s):

Thermodynamic Parameters ◽

Organic Solvents ◽

Sildenafil Citrate ◽

Different Temperatures

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Preparation of Cellulose Stearate and Cellulose Acetate Stearate in 1-Butyl-3-Methylimidazolium Chloride

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.559.105 ◽

2013 ◽

Vol 559 ◽

pp. 105-110 ◽

Cited By ~ 3

Author(s):

Elvira Tarasova ◽

Dmitri Šumigin ◽

M. Kudrjašova ◽

A. Krumme

Keyword(s):

Ionic Liquid ◽

Cellulose Acetate ◽

1H Nmr ◽

Hydroxyl Group ◽

Cellulose Esters ◽

Nmr Data

Cellulose stearates were prepared in a 1-butyl-3-metylimidazolium chloride ionic liquid. The addition of base pyridine as well as catalyst Tin octoate sufficiently increases the degree of hydroxyl group substitution. The new path for preparation of cellulose mixed esters, namely cellulose acetate stearate (CAS), is performed. The 1H NMR data confirmed the structure of obtained mono- and mix- cellulose esters.

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Feasibility Study of Chemical Treatments on Sorghum Fibres for Compatibility Enhancement in Polypropylene Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.929.70 ◽

2018 ◽

Vol 929 ◽

pp. 70-77 ◽

Cited By ~ 1

Author(s):

Ismojo ◽

Rai Pratama ◽

Ghiska Ramahdita ◽

Anne Zulfia Syahrial ◽

Mochamad Chalid

Keyword(s):

Crystallinity Index ◽

Ester Group ◽

Hydroxyl Group ◽

Compatibility Study ◽

Scanning Calorimetry ◽

Polypropylene Composites ◽

Dsc Measurements ◽

Long Time ◽

Weak Compatibility ◽

Pp Composites

Polypropylene (PP) is one of the biggest petro-polymers, which is used in very wide application nowadays. The environment problem due to materials such as plastics having very long time degradability, and critical petroleum sources have promoted some studies to empowerment of natural resources such as natural fibres for substituting or at least modifying petro-polymers. Because of biodegradability obtained from natural source, sorghum fibers are interesting to be used as filler in PP composites, despite of weak compatibility between them. Surface modification on the sorghum fibers through alkalinization prior to acetylation was aimed to improve the fiber compatibility to PP. The treatments were expected to substitute hydroxyl group in the sorghum fibers, into acetic ester group in order to increase their hydrophobicity as the fillers. Moreover, the treatments were able to unbundle single fibers into micro-fibrillated cellulose (MFC) fibres with increase in crystallinity index. Usage of this MFC fiber as filler in PP leads to improvement of the composite performances such as thermal properties. In this study, Fourier Transformation Infra-Red (FTIR) Spectroscopy, X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Field-Emission Scanning Electron Microscope (FE-SEM) were used to evaluate the performances of the Sorghum fibers after the treatments and as the filler in the Sorghum fibers/PP composites. The experimental results showed the MFC fibers as the smallest sizes in 5.0 microns and the highest crystallinity index up to 79.1 %, obtained from alkalinization with 2.5 M NaOH prior to acetylation with 17.4 M CH3COOH and the glacial (CH3CO2)2. Compatibility study of the treated Sorghum fibers on PP shows an improvement indicated by a strong interaction between the fibers and PP on morphology observation, increase in melting point of PP from 163.4°C (using virgin Shorgum fibers) into 163.6°C (using treated Sorghum fibers) in DSC measurements.

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N-Confused porphyrins: complexation and 1H NMR studies

New Journal of Chemistry ◽

10.1039/c7nj01814b ◽

2017 ◽

Vol 41 (16) ◽

pp. 7932-7937 ◽

Cited By ~ 9

Author(s):

Ilya A. Khodov ◽

Olga V. Maltceva ◽

Vladimir V. Klochkov ◽

Oscar I. Koifman ◽

Nugzar Zh. Mamardashvili

Keyword(s):

Organic Solvents ◽

1H Nmr ◽

Nmr Studies ◽

H Nmr ◽

Vis Spectroscopy

The complexation of 2-aza-21-carba-tetraphenylporphyrin and 2-aza-2-methyl-5,10,15,20-tetraphenyl-21-carbaporphyrin with nickel and zinc acetates in organic solvents has been investigated by UV-Vis spectroscopy and 1H NMR.

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Interactions of single and multi-layer graphene oxides with water, methane, organic solvents and HCl studied by 1H NMR

Carbon ◽

10.1016/j.carbon.2013.01.063 ◽

2013 ◽

Vol 57 ◽

pp. 191-201 ◽

Cited By ~ 16

Author(s):

Vladimir M. Gun’ko ◽

Vladimir V. Turov ◽

Raymond L.D. Whitby ◽

Gennadiy P. Prykhod’ko ◽

Alexander V. Turov ◽

...

Keyword(s):

Organic Solvents ◽

1H Nmr ◽

Graphene Oxides ◽

Layer Graphene

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Syntheses, structures, and1H,13C{1H} and119Sn{1H} NMR chemical shifts of a family of trimethyltin alkoxide, amide, halide and cyclopentadienyl compounds

Dalton Transactions ◽

10.1039/c5dt01980j ◽

2015 ◽

Vol 44 (36) ◽

pp. 16156-16163 ◽

Cited By ~ 6

Author(s):

Alejandro G. Lichtscheidl ◽

Michael T. Janicke ◽

Brian L. Scott ◽

Andrew T. Nelson ◽

Jaqueline L. Kiplinger

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Organic Solvents ◽

1H Nmr ◽

Chemical Shifts ◽

Nmr Chemical Shifts ◽

Full Characterization ◽

Nuclear Magnetic

The synthesis and full characterization by Nuclear Magnetic Resonance (1H,13C{1H} and119Sn{1H}) of eleven Me3SnX complexes in six common organic solvents is presented.

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Photo-Crosslinking of Copolymeric Methacrylates Bearing Stilbene Chromophores

Zeitschrift für Naturforschung B ◽

10.5560/znb.2012-0199 ◽

2012 ◽

Vol 67 (11) ◽

pp. 1132-1136

Author(s):

Angelika Jahnke ◽

Herbert Meier

Keyword(s):

Light Scattering ◽

Methyl Methacrylate ◽

Radical Polymerization ◽

Organic Solvents ◽

Imaging Techniques ◽

Ester Group ◽

Cast Films ◽

The Cross ◽

Group Yield

Radical polymerization of methyl methacrylate (2) as major component and the methacrylates 1a or 1b, which contain an (E)-stilbene unit fixed by a tether to the ester group, yield easily soluble copolymers 3a, b. Whereas the dominant photoreactions in solution are (E)⇄Z) isomerizations and intra-chain [2π +2π] cycloadditions, cast films of 3a, b give an inter-chain photo-crosslinking on irradiation. Compared to homopolymers, the copolymers are not only better soluble and more easily processible, their films show less undesired light scattering. The cross-linked material is completely insoluble in organic solvents. Thus, it represents the basis for negative photoresists and the corresponding imaging techniques.

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Determination of Phenolic Hydroxyl Group Content of Milled Wood Lignins (MWL's) from Different Botanical Origins Using Selective Aminolysis, FTIR,1H-NMR, and UV Spectroscopy

Holzforschung ◽

10.1515/hfsg.1992.46.5.425 ◽

1992 ◽

Vol 46 (5) ◽

pp. 425-432 ◽

Cited By ~ 80

Author(s):

O. Faix ◽

C. Grünwald ◽

O. Beinhoff

Keyword(s):

1H Nmr ◽

Uv Spectroscopy ◽

Phenolic Hydroxyl ◽

Hydroxyl Group ◽

Group Content

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Isohexide hydroxy esters: synthesis and application of a new class of biobased AB-type building blocks

RSC Advances ◽

10.1039/c4ra07896a ◽

2014 ◽

Vol 4 (89) ◽

pp. 47937-47950 ◽

Cited By ~ 17

Author(s):

Shanmugam Thiyagarajan ◽

Jing Wu ◽

Rutger J. I. Knoop ◽

Jacco van Haveren ◽

Martin Lutz ◽

...

Keyword(s):

Methyl Ester ◽

Building Blocks ◽

Ester Group ◽

Hydroxyl Group ◽

Secondary Hydroxyl ◽

New Class ◽

New Family ◽

Hydroxy Esters

Here we present the synthesis of a new family of sugar derived 1,4:3,6-dianhydrohexitol based AB-type monomers, containing one methyl ester group and a secondary hydroxyl group in all four possible stereo isomers (RR, RS, SR, SS).

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