Asymmetrie Ethynes. Syntheses of Ethynylferrocene Paradigms

1996 ◽  
Vol 51 (12) ◽  
pp. 1683-1690 ◽  
Author(s):  
Johann Polin ◽  
Herwig Schottenberger ◽  
Karl Eberhard Schwarzhans

Synthetic methods to bifunctional ethynes have been examined. Direct ethynylation, the Stephens-Castro reaction, the Pd-catalysed Hagihara coupling, transmetalation reactions and nucleophilic additions have been evaluated in the preparation of substituted ferrocenylethynes with intended use of these materials in electrochemical and nonlinear optical investigations. Asymmetric ferrocenylethynes are promising candidates for applications in contemporary materials science. Synthetically, 1,4-bis(ferrocenylethynylene)benzene (1), 1,3,5-tris(ferrocenylethynylene) benzene (2), and 9 ,10-bis(ferrocenylethynylene)anthracene (3) are obtained in high yields, whereas 4-ferrocenylethynylene-2,3,5,6-tetrafluorostyrene (4) and potassium (ferrocenylethynylene) triphenyl borate (5) are accessible in only moderate yields. Further extension of this chemistry to additional heteronuclear bimetallic coordination compounds has been attempted, but without success due to severe difficulties in both preparation and characterization of these materials.

Author(s):  
R.T. Blackham ◽  
J.J. Haugh ◽  
C.W. Hughes ◽  
M.G. Burke

Essential to the characterization of materials using analytical electron microscopy (AEM) techniques is the specimen itself. Without suitable samples, detailed microstructural analysis is not possible. Ultramicrotomy, or diamond knife sectioning, is a well-known mechanical specimen preparation technique which has been gaining attention in the materials science area. Malis and co-workers and Glanvill have demonstrated the usefulness and applicability of this technique to the study of a wide variety of materials including Al alloys, composites, and semiconductors. Ultramicrotomed specimens have uniform thickness with relatively large electron-transparent areas which are suitable for AEM anaysis.Interface Analysis in Type 316 Austenitic Stainless Steel: STEM-EDS microanalysis of grain boundaries in austenitic stainless steels provides important information concerning the development of Cr-depleted zones which accompany M23C6 precipitation, and documentation of radiation induced segregation (RIS). Conventional methods of TEM sample preparation are suitable for the evaluation of thermally induced segregation, but neutron irradiated samples present a variety of problems in both the preparation and in the AEM analysis, in addition to the handling hazard.


2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Madalina Angelusiu ◽  
Maria Negoiu ◽  
Stefania-Felicia Barbuceanu ◽  
Tudor Rosu

The paper presents the synthesis and characterization of Cu(II), Co(II), Ni(II), Cd(II), Zn(II) and Hg(II) complexes with N1-[4-(4-bromo-phenylsulfonyl)-benzoyl]-N4-(4-methoxyphenyl)-thiosemicarbazide. The new compounds were characterized by IR, EPR, electronic spectroscopy, magnetic moments, thermo-gravimetric analysis and elemental analysis.


2020 ◽  
Vol 24 (22) ◽  
pp. 2665-2693
Author(s):  
Dipayan Mondal ◽  
Pankaj Lal Kalar ◽  
Shivam Kori ◽  
Shovanlal Gayen ◽  
Kalpataru Das

Indole moiety is often found in different classes of pharmaceutically active molecules having various biological activities including anticancer, anti-viral, anti-psychotic, antihypertensive, anti-migraine, anti-arthritis and analgesic activities. Due to enormous applications of indole derivatives in pharmaceutical chemistry, a number of conventional synthetic methods as well as green methodology have been developed for their synthesis. Green methodology has many advantages including high yields, short reaction time, and inexpensive reagents, highly efficient and environmentally benign over conventional methods. Currently, the researchers in academia as well as in pharmaceutical industries have been developing various methods for the chemical synthesis of indole based compounds via green approaches to overcome the drawbacks of conventional methods. This review reflects the last ten years developments of the various greener methods for the synthesis of indole derivatives by using microwave, ionic liquids, water, ultrasound, nanocatalyst, green catalyst, multicomponent reaction and solvent-free reactions etc. (please see the scheme below). Furthermore, the applications of green chemistry towards developments of indole containing pharmaceuticals and their biological studies have been represented in this review.


2018 ◽  
Vol 21 (7) ◽  
pp. 526-532 ◽  
Author(s):  
Zahra Abdi Piralghar ◽  
Mohammad Mahmoodi Hashemi ◽  
Ali Ezabadi

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.


Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 439
Author(s):  
Monika Rzonsowska ◽  
Katarzyna Kozakiewicz ◽  
Katarzyna Mituła ◽  
Julia Duszczak ◽  
Maciej Kubicki ◽  
...  

A synthesis of a series of mono-T8 and difunctionalized double-decker silsesquioxanes bearing substituted triazole ring(s) has been reported within this work. The catalytic protocol for their formation is based on the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) process. Diverse alkynes were in the scope of our interest—i.e., aryl, hetaryl, alkyl, silyl, or germyl—and the latter was shown to be the first example of terminal germane alkyne which is reactive in the applied process’ conditions. From the pallet of 15 compounds, three of them with pyridine-triazole and thiophenyl-triazole moiety attached to T8 or DDSQ core were verified in terms of their coordinating properties towards selected transition metals, i.e., Pd(II), Pt(II), and Rh(I). The studies resulted in the formation of four SQs based coordination compounds that were obtained in high yields up to 93% and their thorough spectroscopic characterization is presented. To our knowledge, this is the first example of the DDSQ-based molecular complex possessing bidentate pyridine-triazole ligand binding two Pd(II) ions.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1791
Author(s):  
Marco Vizcarra-Pacheco ◽  
María Ley-Flores ◽  
Ana Mizrahim Matrecitos-Burruel ◽  
Ricardo López-Esparza ◽  
Daniel Fernández-Quiroz ◽  
...  

One of the main challenges facing materials science today is the synthesis of new biodegradable and biocompatible materials capable of improving existing ones. This work focused on the synthesis of new biomaterials from the bioconjugation of oleic acid with L-cysteine using carbodiimide. The resulting reaction leads to amide bonds between the carboxylic acid of oleic acid and the primary amine of L-cysteine. The formation of the bioconjugate was corroborated by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and nuclear magnetic resonance (NMR). In these techniques, the development of new materials with marked differences with the precursors was confirmed. Furthermore, NMR has elucidated a surfactant structure, with a hydrophilic part and a hydrophobic section. Ultraviolet-visible spectroscopy (UV-Vis) was used to determine the critical micellar concentration (CMC) of the bioconjugate. Subsequently, light diffraction (DLS) was used to analyze the size of the resulting self-assembled structures. Finally, transmission electron microscopy (TEM) was obtained, where the shape and size of the self-assembled structures were appreciated.


BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi Bi Fatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi

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.


Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1217
Author(s):  
Ewa Jończyk-Matysiak ◽  
Barbara Owczarek ◽  
Ewa Popiela ◽  
Kinga Świtała-Jeleń ◽  
Paweł Migdał ◽  
...  

The aim of this study was the isolation and characterization, including the phage effect on honeybees in laboratory conditions, of phages active against Paenibacillus larvae, the causative agent of American Foulbrood—a highly infective and easily spreading disease occurring in honeybee larva, and subsequently the development of a preparation to prevent and treat this dangerous disease. From the tested material (over 2500 samples) 35 Paenibacillus spp. strains were obtained and used to search for phages. Five phages specific to Paenibacillus were isolated and characterized (ultrastructure, morphology, biological properties, storage stability, and genome sequence). The characteristics were performed to obtain knowledge of their lytic potential and compose the final phage cocktail with high antibacterial potential and intended use of future field application. Preliminary safety studies have also been carried out on healthy bees, which suggest that the phage preparation administered is harmless.


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