Synthese und Eigenschaften von Alkyloxi-und Aryloxi-substituierten Trithiadiborolanen / Synthesis and Properties of Alkoxi and Aryloxi Substituted Trithiadiborolanes

1981 ◽  
Vol 36 (11) ◽  
pp. 1444-1450 ◽  
Author(s):  
Max Schmidt ◽  
Erich Sametschek

Abstract The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group. IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.

1978 ◽  
Vol 33 (4) ◽  
pp. 412-416 ◽  
Author(s):  
Reinhold Tacke ◽  
Roland Niedner

Abstract Organosilicon compounds 8, 9 and 10 with potential curare-like action and their precursors 5, 6 and 7 were synthesized for the first time. 5−10 were characterized by their physical and chemical properties, and their structures were confirmed by analyses, 1 H NMR and mass spectroscopy (only for 5−7). The pharmacological and toxicological data of 8, 9 and 10 are reported.


2021 ◽  
pp. 50-56
Author(s):  
А. В. Хільковець

Nitrogen-containing heterocyclic compounds are widely represented in modern organic chemistry. A special place among the huge number of substances presented is occupied by derivatives of 1,2,4-triazole due to their uniqueness and prospects. In recent years, these derivatives have remained the object of close attention of both synthetic chemists and researchers engaged in the search for new biologically active substances of a wide spectrum of action, the synthesis of optical materials, dyes, corrosion inhibitors, veterinary drugs, etc. It is known from the literature that the combination of the aromatic heterocycle of thiophene and 1,2,4-triazole is a promising area for research. The result of such combinations is a number of compounds obtained with fairly high yields and a wide range of activities. Thus, further chemical modification of 1,2,4-triazole derivatives by additional administration of a typical thiophene pharmacophore is an urgent task. The aim of the study is to obtain new compounds in a number of S-substituted 5-thiophene-(3-ylmethyl)-4R-1,2,4-triazole-3-thiols and study their physico-chemical properties using complex analysis methods. The study of the physical and chemical properties of the compounds obtained was carried out according to methods that meet the standards of the state pharmacopoeia of Ukraine. The synthesis of new compounds was carried out according to generally accepted methods. The previously obtained 5-thiophene-(3-ylmethyl)-4h-1,2,4-triazole-3-thiol and 5-thiophene-(3-ylmethyl)-4-phenyl-1,2,4-triazole-3-thiol were used as starting compounds. Preparation of thioethanones was performed in an alkaline medium in the presence of methanol. The acids were obtained in an alcohol-alkaline medium with the addition of monochloroacetic acid. To obtain esters, two conventional methods were used. The first method is based on the alkylation in an alkaline-alcohol medium of the starting thiols with isopropyl ester of monochloroacetic acid. The second method is the classical esterification reaction. To confirm the structure and study of the physical and chemical properties, all the resulting compounds were crystallized. As a result, some new compounds that were not previously described were obtained, namely: thioethanones, thioacetamides, thioacetic acids, thioacetates, and a number of other thiopo-derivatives of these initial compounds. The structure and individuality of the obtained molecules were confirmed by elemental analysis (CHNS), IR and 1H NMR spectra. A number of new S-derivatives of 5-thiophene-(3-ylmethyl)-4R-1,2,4-triazole-3-thiols have been obtained. The physical and chemical properties of the obtained compounds are determined and their structure is confirmed using modern analysis methods. Some compounds will be transferred for further research.


1979 ◽  
Vol 34 (9) ◽  
pp. 1279-1285 ◽  
Author(s):  
R. Tacke ◽  
M. Strecker ◽  
W. S. Sheldrick ◽  
E. Heeg ◽  
B. Berndt ◽  
...  

Abstract Sila-difenidol (6b), a sila-analogue of the drug difenidol (6a), was synthesized according to Scheme 1. 6b and its new precursors 3 and 5 were characterized by their physical and chemical properties, and their structures confirmed by elementary analyses, 1H NMR and mass spectroscopy. 6 b crystallizes orthorhombic P212121 with a = 11.523(1), b = 14.366(4), c = 11.450(1) Å, Z = 4, Dber = 1.14 gcm-3. The structure was refined to R = 0.050 for 1897 reflexions. A strong nearly linear intramolecular O-H···N hydrogen bond of 2.685 Å is observed. The anticholinergic, histaminolytic and musculotropic spasmolytic activities of 6 a and 6 b are reported.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Jia-Bao Liu ◽  
Hani Shaker ◽  
Imran Nadeem ◽  
Muhammad Hussain

The degree-based topological indices are used to correlate the physical and chemical properties of a molecule with its chemical structure. Boron nanotubular structures are high-interest materials due to the presence of multicenter bonds and have novel electronic properties. These materials have some important issues in nanodevice applications like mechanical and thermal stability. Therefore, they require theoretical studies on the other properties. In this paper, we present certain degree-based topological indices such as ABC, the fourth ABC, GA, and the fifth GA indices for boron triangular and boron-α nanotubes.


1963 ◽  
Vol 41 (5) ◽  
pp. 1276-1280 ◽  
Author(s):  
Malcolm C. Henry ◽  
Wenzel E. Davidson

The successful synthesis of sodium triphenylgermanethiol (1), (C6H5)3GeSNa, and disodium diphenylgermanedithiol, (C6H5)2Ge(SNa)2, have made it possible to carry out reactions with RX type compounds yielding a variety of organogermanium-sulphur compounds. In addition, triphenylgermanethiol, (C6H5)3GeSH, has been synthesized for the first time. Reactions of these compounds are related to analogous group IV element compounds. Physical and chemical properties of these new compounds are also discussed.


2018 ◽  
pp. 60-65
Author(s):  
I. I. Aksyonova-Seliuk ◽  
O. I. Panasenko ◽  
E. G. Knysh

Chemistry of heterocyclic compounds is one of the most popular sector in organic chemistry. Scientists allocate among them a class of derivatives of 1,2,4-triazole. This class of compounds attracts attention his broad spectrum of biological activity. There are antiviral, anti-inflammatory, anti-tubercular, antimicrobial, antioxidant, actoprotective, anti-cancer and other activities. The derivatives of 1,2,4-triazole have one more important advantage. It is low toxicity. This properties do this class of derivatives promising for researches their chemical structure and biological activity and purposeful search of biologically active substances. The purpose of the work is synthesis of 5-(4-(tert-butyl)phenyl)-4-((R)amino)-4H-1,2,4-triazoles-3-thiols from appropriate ylidene derivatives of 4-amino-5-(4 (tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol and research of their physical and chemical properties. The objects of research were 10 new compounds, derivatives of 4-amino-5-(4-(tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol. These compounds are the crystal substances which are odorless, insoluble in water and soluble in organic solvents. Investigation of the physical and chemical properties of this compounds was carried out according to the methods listed in the State Pharmacopoeia of Ukraine. The melting temperature of synthesized compounds was determined by device OptiMelt Stanford Research Systems MPA100. The structure of the compound was confirmed by 1H-NMR spectroscopy (Mercury 400) and gas chromatography-mass spectrometry (Agilent 1260 Infinity HPLC). 10 new compounds, derivatives of 4-amino-5-(4-(tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol, were synthesized in a study. The chemical structure of the new compounds was confirmed by modern instrumental methods of analysis. Results of the done work can be use in the future search of biologically active substances.


1978 ◽  
Vol 33 (1) ◽  
pp. 47-58 ◽  
Author(s):  
Ingo-Peter Lorenz ◽  
John Koshy Thekumparampil

Abstract The synthesis of the sulfinato derivatives 1-7 of pentavalent VB-elements follows equation (2). These compounds differ significantly in their physical and chemical properties and in their structures. In between the extremes of the purely ionic tetramethylam-monium sulfinates la-c and the typically covalent and pentacoordinated tetraorganyl-sulfinato-O-stiboranes 6-7, there are the hexa-or pentavalent compounds of phosphorus and arsenic 2 and 4 or 3 and 5 with sulfinato-O,O' or sulftnato-O linkage, which dissociate readily into their ionic components. 1 a-c are suitable for the synthesis of sulfones according to equation (3). All of the methylsulfinato derivatives can be easily transformed (equation (4)) into the corresponding sulfonates by air oxidation. Only the tetraphenylsulfinato-O-stiboranes 7 a-c show SO2-elimination forming pentaorganylstiboranes (equation (5)). IR, mass and in some cases NMR spectra are reported.


2021 ◽  
Author(s):  
Runzhi Sun ◽  
Xiuqing Song ◽  
Fan Xie ◽  
Huiqin Wang ◽  
Hong Yan

Abstract The structural symmetry is of great significance on the unique physical and chemical properties that closely related to pharmacological applications. To investigate the effects of structural symmetry on the NMR spectra, C2-3,9-diazatetraasteranes and non-C2-3,9-diazatetraasteranes were selected as the research object. They were synthesized by the self-dimerization and cross-dimerization of diethyl 1,4-dihydropyridine-3,5-dicarboxylates, respectively. The differences and similarities in NMR spectra of these two types of 3,9-diazatetraasteranes were discussed by the 1D-NMR and 2D-NMR analysis. The single-crystal X-ray diffraction (XRD) was used to demonstrate directly their structural symmetry.


Background: The technological developments for nanocellulose production from cheaper plant materials compared to wood, in particular, agricultural waste is an urgent task of nanobiophysics. The discovery of possibility of expanding the functional characteristics of materials in compositions with modified cellulose particles essentially stimulated the interest of researchers in cellulose composites. Surface modification of cellulose particles by functional materials, such as dyes, metal oxides, silicon, allows applying composites with modified cellulose in various areas of modern industry. A significant improvement in the operational performances of functionalized cellulose particles can be achieved by using them as filler in polymers. Epoxy resin compositions with modified and unmodified cellulose particles, studied in present work, are an example of hybrid biosystem. The interfacial interaction of filler particles with the epoxy matrix, their concentration and dispersion can change the physical and chemical properties of the biopolymer and the functional parameters of biocomposites. Studying the influence of external fields on the physical and chemical properties of epoxy resin-based biosystems and their influence on operational parameters seems to be an urgent problem of advanced and sustained materials science. Objectives: The purpose of this work was to develop an effective nanocellulose synthesis from plant materials and surface functionalization of micro- and nanocellulose particles with clathrochelate iron (ΙΙ) dye as well obtaining biocompositions of epoxy resin with functionalized and non-functionalized micro- and nanocellulose, and to explore of the morphology, chemical resistance, mechanical and thermal properties of epoxy composites with cellulose micro and nanoparticles. Materials and methods: The studying objects were the composites of epoxy resin Eposir-7120 with a polyethylene polyamine “PEPA” hardener in a ratio of 6.2:1 and 10% cellulose micro and nanoparticles. The microcellulose obtained from wood has been a commercial product. Nanocellulose has been synthesized from organosolv cellulose obtained from Miscanthus x giganteus stalks. Surface modification of micro- and nanocellulose was performed using the clathrochelate iron (ΙΙ) dye. The specific surface area of cellulose particles was determined using low-temperature nitrogen adsorption-desorption according to the Brunauer-Emmett-Teller method. Mechanical parameters were determined using universal Shopper and UMM-10 machines. Thermal analysis was performed using Q1500 analyzer. Swelling was determined by the gravimetric method. Results: Elastic modulus E, compressive strength σ and thermogravimetric parameters were determined. It was shown that in composites with micro and nanocellulose the E rises in 7.0–12.2% while the σ increases in 9.1% for composites with cellulose micro particles. The loading resin with nanocellulose and modified cellulose microparticles no affects the σ value of composites. The thermal stability of epoxy polymer (310°C) reduces after loading with micro and nanocellulose to 290 and 300°C, respectively. Chemical resistance of composites with both celluloses to 20% nitric acid reduces. In neutral medium swelling characterizes by rapid sorption to saturation of 15–20% acetone in 36 hours. Conclusions: Thus, the synthesis method of nanocellulose from plant materials and functionalization of its surface with clathrochelate iron (ΙΙ) were developed. Light response of dye was detected in visible spectral range. Epoxy resin composites with 10% micro and nanocellulose were obtained. The filling effect with micro- and nanocellulose at elastic modulus, compressive strength, and thermal stability of epoxycomposites was studied. The swelling processes run similarly in composites with cellulose micro and nanoparticles.


2021 ◽  
Vol 2131 (4) ◽  
pp. 042044
Author(s):  
D Totskiy ◽  
V Borisova ◽  
A Davidenko ◽  
E Kadochnikova ◽  
N Loran

Abstract The presented article presents the results of investigations of operational characteristics and thermal stability of polymer composites whose matrix is represented by epoxy resins modified with different kinds of inhibiting fillers. An analytical literature review has been performed, methods and methods of obtaining flame retardant composites have been studied. Experimental study of the influence of inhibiting modifiers - fine fillers: iron oxide, silica flour, graphite, talcum, copper oxide has been carried out. According to the results of the experimental study, the modification of the epoxy matrix of the composite by the introduction of inhibiting fillers by ultrasonic treatment contributes to an increase in thermal stability. The modified material is characterized by decrease of intensity of destruction of the material matrix, expressed in decrease of mass loss level, decrease of maximum value of thermal effect, increase of oxidation period, and also steady formation of a thermal insulating carbonaceous layer.


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