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41.
4H,5H-6-Phenyl (1a) and 6-p-phenoxyphenyl (1b) pyridazin-3(2H)-ones were reacted with aromatic aldehydes to give 4-arylmethylpyridazm-3(2H)-ones (2a-g), Oxidation of (2a-g) with various oxidising agents (selenium dioxide in ethanol or chromium trioxide in acetic acid) gave 4-aroyl-6-arylpyridazin-3(2H)-ones (3a-g). Chlorination of (3a-g) with phosphorous oxychloride afforded 4-aroyl-6-aryl-3-chloropyridazine (4a-g). 1H-3-Aryl-5-phenylpyrazolo[3,4-c]pyridazines (5a-d) were obtained by heating (4a-d) with excess hydrazine hydrate. Hydroxyamination of (3e-g) with iydroxylamine gave aryl-4(6-p-phenoxyphenyl-2,3-dihydro-3-oxo)pyridazinyl oxime (6a-c). Silylation of oximes (6b & 6c) gave (7a & 7b) as acyclic compound instead of the expected seven - membered - ring compound (8). 相似文献
42.
Mamdouh W Uji-I H Gesquière A De Feyter S Amabilino DB Abdel-Mottaleb MM Veciana J De Schryver FC 《Langmuir : the ACS journal of surfaces and colloids》2004,20(22):9628-9635
The effect that molecular chirality has on the formation of monolayer structures by pure enantiomers and their racemates at the liquid/solid interface has been investigated for two chiral compounds (1 and 2) which differ from each other by the presence or absence of an ester function in their respective molecular structures. 1 shows pseudoracemate formation when the achiral graphite support is exposed to a solution containing a racemate while 2 shows racemic conglomerate formation. This difference is rationalized in terms of the orientation of the pure enantiomers with respect to the graphite substrate and highlights the importance of molecular structure and its influence on balancing the interplay between molecular conformation and molecular packing on the surface. For 1, nonstoichiometric mixtures of both enantiomers have been investigated, and the results are discussed in the framework of the sergeant and soldiers principle. These results are important for the understanding and prediction of spontaneous resolution in monolayer systems. 相似文献
43.
Abid M. Amin Li Wang Haojie Yu Wael A. Amer Jingmin Gao Tai Yulei 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):937-946
Polydichlorophosphazenes (PDCP) were synthesized through ring opening polymerization of hexachlorocyclotriphosphazene (HCCP). The polymerization behavior of HCCP under varying conditions of time and amount of catalyst was investigated. The chlorine atoms in polydichlorophosphazenes (PDCP) were substituted with p-oxybenzaldehyde and (or) diethylamine to synthesize poly[bis(p-oxybenzaldehyde diethylamino)phosphazenes](PPOBADEAP), poly[bis(p-oxybenzaldehyde)phosphazenes] (PPOBAP) and poly[bis(diethyl amino) phosphazenes] (PDEAP). The supporting evidence for the success of this synthesis was provided by nuclear magnetic resonance (1H-NMR, and 31P-NMR), gel permeation chromatography (GPC), and energy-dispersive X-ray spectroscopy (EDAX). The self-assembly behavior of PPOBADEAP, PPOBAP and PDEAP was observed in different solvents by the same concentration of polymers. The optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images indicated that PPOBADEAP formed various morphologies in different solvents while PPOBAP and PDEAP did not show self-assembly behavior at the same conditions. 相似文献
44.
45.
Ferrocene‐based polymers are characterized by their electrochemical activity, good redox properties, thermal, photochemical stability, and liquid crystallinity, and thus they have various applications in different fields. A comprehensive investigation on the synthesis and properties of three novel main‐chain ferrocene‐based polyesters with azobenzene in the side chain (MFPAS) was carried out. The main‐chain ferrocene‐based polyester, poly(N‐phenyldiethanolamine 1,1′‐ferrocene dicarboxylate (PPFD), was synthesized via the solution polycondensation reaction of 1,1′‐ferrocenedicarbonyl chloride with phenyldiethanolamine (PDE). The novel MFPAS were synthesized via the post‐polymerization azo‐coupling reaction of PPFD with three different 4‐substituted anilines including 4‐nitroaniline, 4‐aminobenzoic acid, and 4‐aminobenzonitrile to produce 4‐nitrophenylazo‐functionalized‐PPFD (PPFD‐NT), 4‐carboxyphenylazo‐functionalized‐PPFD (PPFD‐CA), and 4‐cyanophenylazo‐functionalized‐PPFD (PPFD‐CN), respectively. All the synthesized polymers were characterized by 1H NMR spectroscopy, Fourier transform infrared spectroscopy, and UV–visible spectroscopy. In addition, powder X‐ray diffraction patterns were measured for the synthesized polymers. The photoisomerization of the MFPAS was studied. The thermal properties of the MFPAS were studied using thermogravimetric analysis and differential scanning calorimetry. PPFD‐CA and PPFD‐CN were found to be more thermally stable than PPFD‐NT. Finally, the liquid‐crystalline properties of PPFD and the MFPAS were examined using polarized optical microscope. It was found that all the polymers possessed nematic phases and exhibited textures with schlieren disclinations. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
46.
Dr. Jesko Koehnke Andrew F. Bent David Zollman Kieran Smith Dr. Wael E. Houssen Dr. Xiaofeng Zhu Greg Mann Dr. Tomas Lebl Richard Scharff Dr. Sally Shirran Dr. Catherine H. Botting Prof. Marcel Jaspars Dr. Ulrich Schwarz‐Linek Prof. James H. Naismith 《Angewandte Chemie (International ed. in English)》2013,52(52):13991-13996
47.
Walaa H. El-Shwiniy Manar A. Gamil Sadeek A. Sadeek Wael A. Zordok Ahmed F. El-farargy 《应用有机金属化学》2020,34(8):e5696
The synthesis and characterization of Mn (II), Fe (II), Co (II), Ni (II), Cu (II) and Zn (II) complexes with 3-(bromoacetyl)coumarin (BAC) in presence of 1,10-phenanthroline (Phen) were reported and described by elemental analysis, molar conductivity, FT-IR, UV–Vis and effective magnetic moments. TG and DTG have been applied to study the decomposition mechanisms for BAC, Phen and their complexes. The analytical results and spectral studies showed that BAC and Phen act as bidentate ligands via oxygen of α, β-unsaturated ketone and oxygen of lactone carbonyl of coumarin and two pyridyl nitrogen atoms of Phen. Octahedral geometries have been proposed for all complexes and the kinetic parameter (E*, ΔH*, ΔS* and ΔG*) were calculated using Coats-Redfern (CR) and Horowitz-Metzeger (HM) methods. DFT calculations (bond lengths, bond angles, total energy, heat of formation, dipole moment and the lowest energy model structures) have been determined. The antibacterial activities for synthesized complexes were assayed against some selected bacterial and the complexes displayed a very highly significant against L. monocytogens. 相似文献
48.
A series of Mannich bases were synthesized by a three‐component Mannich reaction. The newly synthesized compounds were well characterized by elemental analyses, IR, NMR and mass spectroscopic studies. The potential antibacterial effects of the synthesized compounds were investigated using standard bacterial strains: Gram‐positive and Gram‐negative bacteria. Interestingly, all the synthesized compounds were observed to be promising leads, possessing moderate to significant inhibitory activity as compared to standard. 相似文献
49.
Rituraj Borah Rajeshreddy Ninakanti Gert Nuyts Hannelore Peeters Adrián Pedrazo-Tardajos Silvia Nuti Prof. Christophe Vande Velde Prof. Karolien De Wael Prof. Silvia Lenaerts Prof. Sara Bals Prof. Sammy W. Verbruggen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):9011-9021
The functionalization of photocatalytic metal oxide nanoparticles of TiO2, ZnO, WO3 and CuO with amine-terminated (oleylamine) and thiol-terminated (dodecane-1-thiol) alkyl-chain ligands was studied under ambient conditions. A high selectivity was observed in the binding specificity of a ligand towards nanoparticles of these different oxides. It was observed that oleylamine binds stably to only TiO2 and WO3, whereas dodecane-1-thiol binds stably only to ZnO and CuO. Similarly, polar-to-nonpolar solvent phase transfer of TiO2 and WO3 nanoparticles could be achieved by using oleylamine, but not dodecane-1-thiol, whereas the opposite holds for ZnO and CuO. The surface chemistry of ligand-functionalized nanoparticles was probed by attenuated total reflectance (ATR)-FTIR spectroscopy, which enabled the occupation of the ligands at the active sites to be elucidated. The photostability of the ligands on the nanoparticle surface was determined by the photocatalytic self-cleaning properties of the material. Although TiO2 and WO3 degrade the ligands within 24 h under both UV and visible light, ligands on ZnO and CuO remain unaffected. The gathered insights are also highly relevant from an application point of view. As an example, because the ligand-functionalized nanoparticles are hydrophobic in nature, they can be self-assembled at the air-water interface to give nanoparticle films with demonstrated photocatalytic as well as anti-fogging properties. 相似文献