Synthesis and Characterization of New Non-aromatic Texaphyrin-type Expanded Porphyrins

Author(s):  
SYLVIE MEYER ◽  
MICHAEL C. HOEHNER ◽  
VINCENT LYNCH ◽  
JONATHAN L. SESSLER

The synthesis and X-ray diffraction-based characterization of a texaphyrin-type non-aromatic expanded porphyrin, 13,18,22,27-tetraethyl-14,17,23,26-tetramethyl-20-p-nitrophenyl-3,10,28,29,30,31-hexaazahexacyclo[23.2.1.04,9.112,15.116,19.121,24]untriaconta-2, 4, 5, 7, 10,12,14,16,18,-20,22,24(30),25,27-tetradecaene (1), is reported. This Schiff base macrocycle was prepared in good yield via the 1:1 HCl -catalyzed condensation of a tetrapyrrole dialdehyde precursor, (di(5-formyl-4,4'-diethyl-3,3'-dimethyl-2,2'-bipyrrole)-p-nitrophenylmethine), with 1,2-phenylenediamine. Compound 1 was assigned as being a 26 π-electron non-aromatic benzannulene on the basis of both proton NMR and single-crystal X-ray diffraction analyses. The latter studies, in particular, revealed a non-planar macrocyclic structure co-crystallized with a molecule of water. By varying either the diamine used in the cyclization step and/or the substituent in the meso-position of the tetrapyrrolic precursor, a range of other systems analogous to 1 could be obtained. The resulting systems were found to present good stability both in the solid state and in solution.

2010 ◽  
Vol 44-47 ◽  
pp. 2299-2306
Author(s):  
H.M.Noor Ul Huda Khan Asghar ◽  
M. Asghar ◽  
M.S. Awan

Polycrystalline spintronic material (Cd0.55Hg0.45Te) was synthesized by conventional solid state reaction. The samples ( = 5 mm and T = 1.5 mm) were prepared by uni-axial pressing. Samples were melted at 800°C for 3-2 hours. For chemical analyses, surface morphology and structural analyses, scanning electron microscopy (SEM) equipped with EDX system and X-ray diffraction studies were performed. XRD confirmed the cubic crystal structure. The Lattice constant of (Cd0.55Hg0.45Te) as determined by XRD was 0.6464 nm. The Miller indices (hkl) have been found by using crystallography method. The observed planes were (200), (210) and (331). The EDX analyses showed the typically compositions: Te 24.8% Cd 14.8% Al 5% and O2 46.4 % & C 9% (3 hours treatment) and Te 28.1% Cd 16% Al 4.1% and O2 39.3 %, Si 0.360% & C 12.1% (2 hours treatment) however we could not find any representative peak for Hg in all of the EDX analyses.


2010 ◽  
Vol 13 (1-2) ◽  
pp. 17
Author(s):  
K.V.R. Murthy ◽  
K. Suresh ◽  
B. Nageswara Rao ◽  
B. Walter Ratna Kumar ◽  
Ch. Atchyutha Rao ◽  
...  

<p>The present paper reports the Photoluminescence (PL) of the Sr<sub>2</sub>CeO<sub>4</sub> phosphor, singly doped with Erbium rare-earth ion with different concentrations (0.01, 0.1, 0.2, 0.5 and 1%).The phosphor samples were synthesized using the standard solid state reaction technique. The effect of Er dopant on the structural, morphological, and Photoluminescent properties of the samples are studied with X-ray diffraction (XRD), PL and SEM analysis. The PL emission of undoped Sr<sub>2</sub>CeO<sub>4</sub> phosphor was observed at 470 nm with high intensity followed by the primary Er emissions with good intensity at 525, 530, 549, 557 and 565 nm.</p>


2011 ◽  
Vol 66 (9) ◽  
pp. 947-952
Author(s):  
Meiling Xu ◽  
Yong Nie ◽  
Jinling Miao ◽  
Zhenwei Zhang ◽  
Bin Peng ◽  
...  

The reactions of the dithiolato-o-carborane salt (Et3NH)2(S2C2B10H10) (2) with alkyl halides BrCH2CH=CH2, BrCH2CH2CH2Cl and C6H5CH2Cl, afford the o-carboranyl-bisthioether derivatives 3a - c, which have been characterized by IR and NMR (1H, 13C, 11B) spectroscopy, mass spectrometry, and single-crystal X-ray diffraction (3c). The photoluminescent properties of the known compound 3c has been investigated. It exhibits a violet (chloroform solution) or blue (solid state) emission when excited with UV light.


2002 ◽  
Vol 67 (6) ◽  
pp. 808-812 ◽  
Author(s):  
Sundargopal Ghosh ◽  
Alicia M. Beatty ◽  
Thomas P. Fehlner

The rhenaborane Cp*ReH3B3H8, which is generated by the reaction of Cp*ReH6 with BH3·THF, has been characterized spectroscopically in solution and by a single-crystal X-ray diffraction study in the solid state as a hydrogen-rich arachno-metallatetraborane.


2021 ◽  
Vol 9 ◽  
Author(s):  
Campbell F. R. Mackenzie ◽  
Lucie Delforce ◽  
D. Rota Martir ◽  
David B. Cordes ◽  
Alexandra M. Z. Slawin ◽  
...  

[2.2]Paracyclophane scaffolds have seen limited use as building blocks in supramolecular chemistry. Here, we report the synthesis and characterization of a 1D coordination polymer consisting of silver(I) ions bound to a [2.2]paracyclophane scaffold functionalized with two 4-pyridyl units. The structure of the polymer has been determined from single crystal X-ray diffraction analysis and reveals two different silver coordination motifs that alternate along the 1D coordination polymer. The coordination polymer exhibits strong blue and sky-blue fluorescence in solution and in the crystalline solid state, respectively.


Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 323 ◽  
Author(s):  
Mahmoudi ◽  
Seth ◽  
Zubkov ◽  
López-Torres ◽  
Bacchi ◽  
...  

Herein, we describe the synthesis and single crystal X-ray diffraction characterization of several Pb(II) complexes using Schiff base hydrazido-based ligands and different counterions (NO3−, I– and ClO4). In the three complexes reported in this work, the lead(II) metal exhibits a high coordination number (n > 8) and thus it is apparently not involved in tetrel bonding interactions. Moreover, the aromatic ligands participate in noncovalent interactions that play an important role in the formation of several supramolecular assemblies in the solid state of the three Pb(II) complexes. These assemblies have been analyzed by means of Hirshfeld surface analysis and DFT calculations.


2014 ◽  
Vol 802 ◽  
pp. 285-290 ◽  
Author(s):  
Mônica C. de Andrade ◽  
Geysa N. Carneiro ◽  
Elizabeth L. Moreira ◽  
Jorge C. Araújo ◽  
Valéria C.A. Moraes

Solid-state reactions were used to synthesize pure and doped barium titanate powder. Barium titanate formation with tetragonal perovskite structure was detected by X-ray diffraction and occurred at a temperature above 700°C for pure powder and 500°C for doped powder. However, quite crystalline samples were observed only at 800oC and 600°C for pure and doped barium titanate, respectively, what made the refinement of the synthesized powders possible. They were characterized by X-ray diffraction and Fourier transform infrared spectroscopy and scanning electron microscopy. X-ray diffraction data was analyzed by using the Fullprof Rietveld refinement approach, Thompson-Cox-Hastings pseudo-Voigt with function. The refinement method was effective in the study of the temperature influence on the microstructure of the analysis of pure and doped barium titanate.


2018 ◽  
Vol 2 (1) ◽  
pp. 7
Author(s):  
S Chirino ◽  
Jaime Diaz ◽  
N Monteblanco ◽  
E Valderrama

The synthesis and characterization of Ti and TiN thin films of different thicknesses was carried out on a martensitic stainless steel AISI 410 substrate used for tool manufacturing. The mechanical parameters between the interacting surfaces such as thickness, adhesion and hardness were measured. By means of the scanning electron microscope (SEM) the superficial morphology of the Ti/TiN interface was observed, finding that the growth was of columnar grains and by means of EDAX the existence of titanium was verified.  Using X-ray diffraction (XRD) it was possible to observe the presence of residual stresses (~ -3.1 GPa) due to the different crystalline phases in the coating. Under X-ray photoemission spectroscopy (XPS) it was possible to observe the molecular chemical composition of the coating surface, being Ti-N, Ti-N-O and Ti-O the predominant ones.


2019 ◽  
Vol 15 (8) ◽  
pp. 850-862
Author(s):  
Mirthala Flores-García ◽  
Juan Manuel Fernández-G. ◽  
Cristina Busqueta-Griera ◽  
Elizabeth Gómez ◽  
Simón Hernández-Ortega ◽  
...  

Background: Ischemic heart disease, cerebrovascular accident, and venous thromboembolism have the presence of a thrombotic event in common and represent the most common causes of death within the population. Objective: Since Schiff base copper(II) complexes are able to interact with polyphosphates (PolyP), a procoagulant and potentially prothrombotic platelet agent, we investigated the antiplatelet aggregating properties of two novel tridentate Schiff base ligands and their corresponding copper( II) complexes. Methods: The Schiff base ligands (L1) and (L2), as well as their corresponding copper(II) complexes (C1) and (C2), were synthesized and characterized by chemical analysis, X-ray diffraction, mass spectrometry, and UV-Visible, IR and far IR spectroscopy. In addition, EPR studies were carried out for (C1) and (C2), while (L1) and (L2) were further analyzed by 1H and 13C NMR. Tests for antiplatelet aggregation activities of all of the four compounds were conducted. Results: X-ray diffraction studies show that (L1) and (L2) exist in the enol-imine tautomeric form with a strong intramolecular hydrogen bond. NMR studies show that both ligands are found as enol-imine tautomers in CDCl3 solution. In the solid state, the geometry around the copper(II) ion in both (C1) and (C2) is square planar. EPR spectra suggest that the geometry of the complexes is similar to that observed in the solid state by X-ray crystallography. Compound (C2) exhibited the strongest antiplatelet aggregation activity. Conclusion: Schiff base copper(II) complexes, which are attracting increasing interest, could represent a new approach to treat thrombosis by blocking the activity of PolyP with a potential anticoagulant activity and, most importantly, demonstrating no adverse bleeding events.


Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 721 ◽  
Author(s):  
Jorge A. Ramírez-Gómez ◽  
Javier Illescas ◽  
María del Carmen Díaz-Nava ◽  
Claudia Muro-Urista ◽  
Sonia Martínez-Gallegos ◽  
...  

Atrazine (ATZ) is an herbicide which is applied to the soil, and its mechanism of action involves the inhibition of photosynthesis. One of its main functions is to control the appearance of weeds in crops, primarily in corn, sorghum, sugar cane, and wheat; however, it is very toxic for numerous species, including humans. Therefore, this work deals with the adsorption of ATZ from aqueous solutions using nanocomposite materials, synthesized with two different types of organo-modified clays. Those were obtained by the free radical polymerization of 4-vinylpyridine (4VP) and acrylamide (AAm) in different stoichiometric ratios, using tetrabutylphosphonium persulfate (TBPPS) as a radical initiator and N,N′-methylenebisacrylamide (BIS) as cross-linking agent. The structural, morphological, and textural characteristics of clays, copolymers, and nanocomposites were determined through different analytical and instrumental techniques, i.e., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption kinetics experiments of ATZ were determined with the modified and synthesized materials, and the effect of the ratio between 4VP and AAm moieties on the removal capacities of the obtained nanocomposites was evaluated. Finally, from these sets of experiments, it was demonstrated that the synthesized nanocomposites with higher molar fractions of 4VP obtained the highest removal percentages of ATZ.


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