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1.
Synthesis of 4,4-bis(4-aminophenoxy)benzophenone was performed starting from chloral. Various polyimides were obtained by reactions of 4,4 -bis(4-aminophenoxy)benzophenone with aromatic tetracarboxylic acid dianhydrides. Some of the polyimides obtained are crystalline compounds.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 673–676, March, 1996.  相似文献   

2.
3.
First representatives of dichloroamino- and chloroaminofurazans, viz., 4,4′-bis(dichloroamino)- and 4,4′-bis(chloroamino)-3,3′-azofurazans, were synthesized by the chlorination of 4,4′-diamino-3,3′-azofurazan with sodium hypochlorite in the CH2Cl2—H2O mixture.  相似文献   

4.
Oligo(aryloxyphosphazenes) are synthesized on the basis of diphenylolpropane and hexachlorocyclotriphosphazene via the phenolate method. Corresponding functional derivatives are obtained through treatment of the oligomers with methacryloyl chloride, glycidyl methacrylate, and epichlorohydrin. GPC data indicate that modification is accompanied by an increase in the molecular mass of the oligomers. Epoxidation of a specially synthesized hexaallyloxy derivative of oligo(aryloxycyclotriphosphazene) with m-chloroperbenzoic acid proceeds incompletely to yield an oligomer with a content of epoxy groups below 6%. All of the compounds are characterized with the use of 31P and 1H NMR spectroscopy.  相似文献   

5.
N,N′-Bis[(1-methyl-3-oxobutylidene)hydrazinocarbonylethyl]-, N,N′-bis[(2,5-dimethylpyrrol-1-yl)carbamoylethyl]-, N,N′-bis(phenylureidocarbamoylethyl)-, N,N′-bis(phenylcarbamoyl)-, N,N′-bis(phenylureidocarbamoylethyl)-, and N,N′-bis[(4,5-dihydro-5-oxo-4-phenyl-1,2,4-triazol-3-yl)ethyl]-1,4-phenylene-diamines, and their thio analogs were obtained by the condensation of N,N′-bis-(hydrazinocarbonylethyl)-1,4-phenylenediamine with 2,4-pentanedione, 2,5-hexanedione, phenyl isocyanates, or phenyl isothiocyanates (with subsequent treatment of the obtained semicarbazides with alkali), and carbon disulfide respectively.  相似文献   

6.
Bis(2,4,7,8,9-pentamethyldipyrrolylmethene-3-yl)(4′-methoxyphenyl)methane dihydrobromide was synthesized and its spectral properties were studied. It was found that the basicity of the ligand 3,3′-bis-(dipyrrolylmethene) decreases upon insertion of the methoxyphenyl group in the 3,3′-spacer.  相似文献   

7.
Dehydrogenation of pentafluorophenylgermane in the presence of catalytic amounts of a Wilkinson complex, certain RhI ortho-benzosemiquinolate complexes, or (Ph3P)4Pt leads to tetrahydrodigermane, C6F5H2GeGeH2C6F5. X-ray analysis has confirmed thetrans-arrangement of the C6F5-cycles at the Ge atoms. The Ge-Ge bond length is 2.394(1) Å. The doublet pattern of the band due to the Ge-H bonds (v 2090 and 2104 cm–1) in the IR spectrum is probably associated with nonequivalence of the hydrogen atoms in the molecule.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 315–318, February, 1994.  相似文献   

8.
9.
A new aromatic diamine, 1,1-bis(4-aminophenyl)-1-{4′-bis(4″-bromophenyl)amino}phenyl-2,2,2-trifluoroethane, is synthesized. Its interaction with various dianhydrides of aromatic carboxylic acids via high-temperature polycondensation yields a number of new functionalized poly(imides) combining high thermal and mechanical characteristics with solubility in organic solvents. The values of T g vary from 208 to 230°C, and temperatures corresponding to 10% weight loss fall within the intervals 330–370 and 550–660°C (in air and argon, respectively). Spectroelectrochemical characteristics of poly(imides) are studied by cyclic voltammetry and UV-VIS spectrometry. Poly(imides) exhibit high reversible stability of electrochromic properties, and their color changes from colorless (the neutral form) to green (the oxidized form) as the applied potential is varied from 0 to 1.25 V.  相似文献   

10.
Four new alkyl-substituted 3,3′-bis(dipyrrolylmethene) dihydrobromides containing from 4 to 10 alkyl substituents were synthesized. In a highly alkylated ligand of these substances one of the hydrogen atoms of the 3,3′-methylene spacer was substituted with a phenyl group. The compounds obtained were studied by IR, 1H NMR, electron absorption, and fluorescent spectroscopy. The increased alkylation degree of pyrroles and the introduction of an aryl substituent in the 3,3′-spacer causes a significant high-frequency shift of the N-H stretching vibrations in the IR spectra, an upfield shift of the NH-proton signals in 1H NMR spectra, a decrease in the auxochromic effects of protons on the aromatic system of chromophore in the composition of salts. The red shift of maximum of the strong band in electron absorption spectra and the emission spectra of compounds in DMF, DMSO, C5H5N, C6H6, and CHCl3 was established. The salts obtained are stable in benzene and chloroform, while in electron-donor solvents the irreversible processes of solvolytic dissociation of salts to free organic base and HBr take place.  相似文献   

11.
1,4-Dicyanobenzene and 4,4′-diaminodiphenyl oxide at 190–200°C in ionic liquids form polyamidines of different molecular weights, whose T 10% in air is in the range 250–270 °C.  相似文献   

12.
To investigate the construction of interpenetrating coordination networks and the effect of ligands, [Zn(bimb)(bdc)]·H2O (1) and [Zn(bimb)(Hbtc)]·H2O (2) [bimb?=?4,4′-bis(1H-imidazol-1-yl-methyl)biphenyl; H2bdc?=?1,2-benzenedicarboxylic acid; H3btc?=?1,3,5-benzenetricarboxylic acid] were hydrothermally synthesized and characterized by elemental analysis, IR spectra, Powder X-ray diffraction, and thermogravimetric analysis. Complex 1 shows a 3-D uoc type topology with twofold interpenetration. However, 2 exhibits a different 2-D self-penetrating network owing to hydrogen bonds of Hbtc between the two interpenetrating sql sheets, indicating that different carboxylic ligands could affect the interpenetration structures. Photoluminescence of bimb and the two complexes are also studied.  相似文献   

13.
Two coordination complexes, [Co2L2(4,4′-bpy)2(H2O)4]?·?6H2O (1) and [CoL(4,4′-bpy)] (2) (H2L?=?4,6-bis(4-methylbenzoyl)isophthalic acid and 4,4′-bpy?=?4,4′-bipyridine), have been synthesized with the same starting materials under conventional and hydrothermal condition, respectively. Their structures have been characterized by X-ray diffraction, elemental analysis, IR spectra, and thermogravimetric analysis. Complex 1 features a 2-D sheet structure (space group C2/c) with (4,4) grid units. The non-covalent interactions (O–H?·?·?·?O, C–H?·?·?·?π, and weak π??·?·?·?π interactions) extend 1 into a 3-D supramolecular network. Complex 2 displays a (3,5)-connected network (space group P 1) with a (42?·?6)(42?·?68) topology.  相似文献   

14.
To further explore the coordination possibilities of naphthalene-based carboxylic acids, a ZnII coordination polymer, [Zn3(L)6(bipy)2] n (1), with bulky 2-naphthol-5-carboxylate (L) and bridging 4,4′-bipyridine (bipy), was synthesized and characterized. Structural analysis reveals that 1 is a 1-D polymeric chain with trinuclear units as nodes, which are further extended via interchain secondary interactions, such as O–H ··· O hydrogen-bonding and aromatic π ··· π stacking interactions, to form an overall 3-D framework. Complex 1 exhibits strong solid-state luminescence emission at room temperature, mainly originating from intraligand π→π* transition of L.  相似文献   

15.
Latent epoxide oligomers of N-glycidyl-ortho-chloroaniline and 4,4′-diamino-3,3′-dichlorodiphenylmethane were synthesized that are capable of self-curing and forming films at elevated temperatures and their reactivity was studied. Thermostable polymer composition materials that are waterproof and characterized by high stability were designed and tested.  相似文献   

16.

Binuclear non-symmetrical phosphor(???)arene macrocyclic phosphonite bearing different aromatic fragments (Ar1 ≠Ar2) was synthesized using two different bisphenols (4,4′-iminodiphenol and 4,4′-methylenediphenol) as the starting material. The characteristic properties of the synthesized macrocycle that confirm its structure, in particular, oxidation and sulfurization reactions, were studied.

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17.
《Supramolecular Science》1996,3(4):215-220
A new tetracationic cyclophane, cyclobis(4,4′-azopyridinium-p-phenylene) (2.4PF6), was synthesized via template-directed synthesis and characterized by MS and NMR spectroscopy. For the preparation of π-electron-deficient 2.4PF6, the use of π-electron-rich templates such as 1,4-bis[2-(2-hydroxyethoxy)ethoxy]-benzene (4) and 1,5-bis[2-(2-hydroxyethoxy)ethoxy]naphthalene (5) enhanced the cyclophane formation in 17 and 19% yields, respectively. 1H NMR spectra of the reaction mixture revealed that the cyclophane precursor 1.2PF6 formed supramolecular assembling complexes with hydroquinone derivatives 4 and 5 before the ring formation. The intermolecular charge transfer interaction and the stability constants (Ka) of complexes generated between the electron-acceptor 2.4PF6 and electron-donors 1,4-dimethoxybenzene 3, 4, and 5 were evaluated using UV-vis. spectroscopy and spectroscopic titration. The absorption bands attributable to CT interactions were centred at 580 nm for 3, 635 nm for 4, and 646 nm for 5, with stability constants of 17 ± 2, 2100 ± 200, and 2400 ± 300, respectively.  相似文献   

18.
The side reaction of macrocyclization that occurs during the synthesis of poly-(1,4-phenylenesulfide ketone) by polycondensation of a 4,4-dihalobenzophenone with sodium sulfide was studied. It was found that the major product of this reaction is a cyclic trimer, cyclotris-(4,4"-thiodiphenylene ketone) (1). Despite the fact that ketone bridges are more rigid than sulfide bridges, the yield of the macrocycle is rather high, as it is in the synthesis of poly-(1,4-phenylenesulfide), and reaches 20% under high dilution conditions. The structure of 1 was investigated by X-ray diffraction analysis (R = 0.069 on 3138 reflections). Macrocycle 1 is strongly flattened in the crystal; the conformation observed is determined by the packing, since stereochemical analysis indicates high flexibility of the macrocycle. The solvate acetone molecules incorporated in the crystal are disordered, nevertheless, they are strongly fixed in the cavities and channels of the crystal structure.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1460–1466, August, 1994.  相似文献   

19.
Hydrobromides of three new alkyl-substituted tetrapyrrole ligands with an open chain, in which the dipyrrolylmethene fragments are linked by a CH2-spacer at the 3,3′-pyrrole carbon atoms, were synthesized and studied by IR, 1H NMR, and electronic absorption spectroscopy. As compared to the 2,2′ isomers (alkyl derivatives of biladiene-a,c) and monomers (2,2′-, 2,3′-, and 3,3′-dipyrrolylmethenes, the effect of structural factors is manifested in a considerable (up to 19–31 nm) bathochromic shift of the strong band in the electronic spectrum, an increase in the N-H stretching vibration frequency in the IR spectra (by more than 30 cm?1), and a decrease in the stability of 3,3′-bis(dipyrrolylmethene) salts. The solvent effect is manifested in small changes in the quantitative characteristics of the electronic absorption spectra of 3,3′-tetrapyrrole hydrobromides in C6H6, CCl4, CH2Cl2, CHCl3, and alcohols. In DMF, DMSO, and C5H5N, the salts undergo solvolytic dissociation to the free ligands and HBr, which accelerates in dilute solutions (<10?4 M) and with an increase in the electron-donor power of the solvent. The auxochromic effects of protons in the electronic absorption spectra of the salts, compared to ligands, were estimated quantitatively.  相似文献   

20.
A simple, rapid and efficient synthesis of 4,4′-dimethylamino-diphenyl diselenide 1 and 4,4′-dinitrodiphenyl diselenide 2 is described. The method consists of the reductive cleavage of the Se-CN linkage in the corresponding aryl selenocyanates by sodium borohydride followed by air oxidation of the resulting seleno-lates. The diselenides 1 and 2 are readily obtained in a state of high purity, in 89 and 80% yield, respectively.  相似文献   

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