The selective monobromination of a highly sterically encumbered corrole: Structural and spectroscopic properties of Fe(Cl)(2-bromo-5,10,15-tris(triphenyl)phenyl corrole)

2021 ◽  
pp. A-J
Author(s):  
Jessica G. Alvarado ◽  
Daniel C. Cummins ◽  
Andrada C. Diaconescu ◽  
Maxime A. Siegler ◽  
David P. Goldberg
Keyword(s):  
Cyclic Voltammetry ◽  
Complex Analysis ◽  
Spectroscopic Properties ◽  
Chloride Complex ◽  
Iron Chloride ◽  
Mossbauer Spectrum ◽  
Chemical Transformations ◽  
Catalytic Systems ◽  
High Yields

The corrole ligand serves as a versatile tri-anionic, macrocyclic platform on which to model biological catalytic systems, as well as to effect mechanistically challenging chemical transformations. Herein we describe the synthesis, structure, and characterization of an isomerically pure corrole ligand, selectively mono-brominated at the β-carbon position adjacent to the corrole C-C bond (2-C) and produced in relatively high yields, as well as its iron chloride complex. Analysis of the iron metalated complex by cyclic voltammetry shows that the bromine being present on the ligand resulted in anodic shifts of +93 and +63 mV for first oxidation and first reduction of the complex respectively. The Mössbauer spectrum of the iron metalated complex shows negligible change relative to the non-brominated analog, indicating the presence of the halide substituent predominantly effects the orbitals of the ligand rather than the metal.

Synthese und Charakterisierung von 1,3,5-Hexahydrotriazin-Komplexen des Moo und MoVI / Synthesis and Characterization of 1,3,5-Hexahydrotriazine Complexes of Mo0 and M oVI

1995 ◽  
Vol 50 (7) ◽  
pp. 1038-1044 ◽  
Author(s):  
Hans Schumann
Keyword(s):  
Mass Spectroscopy ◽  
Spectroscopic Properties ◽  
Macrocyclic Ligands ◽  
Synthesis And Characterization ◽  
Controlled Conditions ◽  
Ligand Displacement ◽  
High Yields

Organo-substituted 1,3,5-hexahydrotriazine complexes of the type (RNCH2)3Mo(CO)3 (R = CH3, i - C3H7 and CH2C6H5) are obtained by ligand displacement from η6-C7H8Mo(CO)3 in high yields. These products have been characterized by 1H, 13C, 95Mo NMR, IR as well as mass spectroscopy and contain an electron-rich Mo(C O)3 center bonded to the 1,3,5-hexahydrotriazine 6e donor via three Mo -N bonds. Oxidation of the Mo0 complex 1,3,5-(CH3NCH2)3Mo(CO)3 with H2O2 under carefully controlled conditions allows isolation of 1,3,5-(CH3NCH2)3MoO3 containing a MoVI center. Chemical and spectroscopic properties of these complexes are compared with those of related Mo complexes with neutral macrocyclic ligands containing N3 donor sets.

Synthesis and Characterization of a Novel Ionic Liquid Based on N,N,N,N-tetramethylethylenediamine and its Application in the Synthesis of 1,8-dioxo-octahydro Xanthenes

2018 ◽  
Vol 21 (7) ◽  
pp. 526-532 ◽  
Author(s):  
Zahra Abdi Piralghar ◽  
Mohammad Mahmoodi Hashemi ◽  
Ali Ezabadi
Keyword(s):  
Ionic Liquid ◽  
Chlorosulfonic Acid ◽  
Solvent Free ◽  
Aryl Aldehydes ◽  
Acidic Ionic Liquid ◽  
Brønsted Acidic Ionic Liquid ◽  
Solvent Free Conditions ◽  
Aryl Aldehyde ◽  
High Yields

Aim and Objective: In this work, we synthesized and characterized a novel Brönsted acidic ionic liquid from the reaction of N, N, N’, N’-tetramethylethylenediamine with chlorosulfonic acid and explored its catalytic activity in 1, 8-dioxo-octahydroxanthenes synthesis. Materials and Methods: Dimedone, aryl aldehydes, and the ionic liquid as the catalyst were reacted under solvent-free conditions. The progressive of the reaction was monitored by a thin layer of chromatography (ethyl acetate/n-hexane = 1/5). All products were characterized as the basis of their spectra data and melting point by comparison with those reported in the literature. Results: The prepared ionic liquid was successfully applied in the synthesis of 1, 8-dioxooctahydroxanthenes in good to high yields on the reaction of aryl aldehyde and dimedone at 120oC under solvent-free conditions. Conclusion: This research demonstrates that the catalyst is impressive for 1, 8-dioxo-octahydroxanthenes synthesis under solvent-free conditions.

scholarly journals Rapid four-component synthesis of dihydropyrano[2,3-c]pyrazoles using nano-eggshell/Ti(IV) as a highly compatible natural based catalyst

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi Bi Fatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Reaction Times ◽  
Diffraction Field ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Work Up

AbstractNano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are mild condition, short reaction times, easy work-up, high yields, reusability of the catalyst and the absence of toxic organic solvents.

Synthesis and characterization of novel functionalized perarylated polysiloxane for proton exchange membrane fuel cells

MRS Advances ◽  
2019 ◽  
Vol 4 (64) ◽  
pp. 3579-3585
Author(s):  
Guillermo M. González Guerra ◽  
Alejandro Alatorre-Ordaz ◽  
Gerardo González Garcia ◽  
Jesus S. Jaime-Ferrer
Keyword(s):  
Cyclic Voltammetry ◽  
Fuel Cells ◽  
Proton Exchange Membrane ◽  
Area Under The Curve ◽  
Chlorosulfonic Acid ◽  
Proton Exchange ◽  
Synthesis And Characterization ◽  
A Value ◽  
Exchange Membrane

ABSTRACTThis work presents the synthesis and characterization of a pearylated polysiloxane material (PAP) from a polycondensation reaction, followed by functionalization with HClSO3 by an electrophilic substitution reaction. According to the characterization techniques applied, a sulfonated pearylated polysiloxane was also obtained, (SPAP). The purpose of this sulfonated material is to obtain an ionomer able to be applied in hydrogen fuel cells of the proton exchange membrane kind (PEMFC). The reaction to produce the polysiloxane precursor was carried out with the commercial reagents: PhSiCl3, Ph2SiCl2 and Ph3SiCl in anhydrous THF at 75 °C and the SPAP material was obtained by sulfonation of the precursor with chlorosulfonic acid. PAP and SPAP were characterized by 1H, NMR for liquids, 29Si NMR for solids, IR-ATR, SEM, and cyclic voltammetry. The NMR 29Si spectra show that PAP and PAPS contain crosslinking regions due to PhSiCl3, growing chain zones due to Ph2SiCl2 and polymer termination zones due to Ph3SiCl, obtaining a mixture of siloxanes. The analysis by cyclic voltammetry indicates that by integrating the area under the curve of the adsorption peaks of H2, a value of 0.062 mC/cm2 is obtained, a value close to the commercial ionomer of Nafion®.

Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds

Holzforschung ◽  
2012 ◽  
Vol 66 (3) ◽  
Author(s):  
Takumi Shiraishi ◽  
Toshiyuki Takano ◽  
Hiroshi Kamitakahara ◽  
Fumiaki Nakatsubo
Keyword(s):  
Electron Transfer ◽  
Cyclic Voltammetry ◽  
Carbonyl Compounds ◽  
Model Compounds ◽  
Lignin Model Compounds ◽  
Bulk Electrolysis ◽  
Lignin Model ◽  
Dimeric Compound ◽  
High Yields ◽  
Short Time

Abstract The direct anodic oxidation of non-phenolic lignin model compounds was investigated to understand their basic behaviors. The results of cyclic voltammetry (CV) studies of monomeric model, such as 1-(4-ethoxy-3-methoxyphenyl)ethanol, are interpreted as the oxidation for Cα-carbonylation did not proceed in the reaction without a catalyst, but a base promotes this reaction. Indeed, the bulk electrolyses of the monomeric lignin model compounds with 2,6-lutidine afforded the corresponding Cα-carbonyl compounds in high yields (60–80%). It is suggested that deprotonation at Cα-H in the ECEC mechanism (E=electron transfer and C=chemical step) is important for Cα-carbonylation. In the uncatalyzed bulk electrolysis of a β-O-4 model dimeric compound, 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, the corresponding Cα-carbonyl compound was not detected but as a result of Cα-Cβcleavage 4-O-ethylvanillin was found in 40% yield. In the electrolysis reaction in the presence of 2,6-lutidine (as a sterically hindered light base), the reaction stopped for a short time unexpectedly. These results indicate the different electrochemical behavior of simple monomeric model compounds and dimeric β-O-4 models. The conclusion is that direct electrooxidation is unsuitable for Cα-carbonylation of lignin.

Cyclic Voltammetry Characterization of Microparticle Monolayers

2014 ◽  
Vol 133 ◽  
pp. 241-246 ◽  
Author(s):  
Magdalena Nosek ◽  
Piotr Batys ◽  
Michał Skoczek ◽  
Paweł Weroński
Keyword(s):  
Cyclic Voltammetry

Synthesis and Characterization of a Methanofullerene-4-Fluoro-α-Cyanostilbene Dyad as a Potential Acceptor for Organic Solar Cells

2015 ◽  
Vol 1784 ◽  
Author(s):  
Venkata Neti
Keyword(s):  
Mass Spectrometry ◽  
Cyclic Voltammetry ◽  
Solar Cells ◽  
Organic Solar Cells ◽  
Synthesis And Characterization ◽  
Lumo Energy ◽  
Homo Lumo ◽  
Aryl Ester

ABSTRACTA series of fluorine appended highly conjugated fullerenes were prepared containing fluoro-α-cyanostilbene and aryl ester units. These modified PCBM dyads are fully characterized by NMR, Mass spectrometry, UV-vis, and cyclic voltammetry (Figures 1-4). It was found that the presence of fluoro-α-cyanostilbenes and esters affects the cyclic voltammetry and absorption in the UV-Vis region. The PCBA modified fullerenes significantly influences the HOMO-LUMO energy and wide absorption compared to PCBM.

Bulinga izpausmes skolā: kriminoloģiskās problēmas

2021 ◽  
pp. 258-268
Author(s):  
Aldona Kipāne
Keyword(s):  
Theoretical Analysis ◽  
Research Methods ◽  
Complex Analysis ◽  
Health And Safety ◽  
Document Analysis ◽  
Violent Behaviour ◽  
Long Time ◽  
Empirical Research Methods ◽  
Insight Into

The article gives an insight into criminological problems of bullying in school phenomena. Although the term “bullying” is a modern word, such behaviour has been known for a long time. Bullying is a manifestation of violent behaviour, which threatens the victim's health and safety. The aim of this article is to describe and analyse bullying as a form of expression of violence, showing the criminological aspects of this phenomenon. To achieve the aim of the article the following tasks are defined: to provide the theoretical and practical framework of the research phenomenon, to study and evaluate certain elements of the criminological characterization of the bullying: the description of a victim and a perpetrator, the evaluation of factors and directions of prevention. Theoretical analysis methods such as deconstruction, descriptive and complex analysis, and empirical research methods – document analysis, comparison and compilation were employed in this study.

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