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1.
A novel diamine, bis(3‐aminophenyl)‐4‐(1‐adamantyl)phenoxyphenyl phosphine oxide (mDAATPPO), was synthesized via the Williamson ether reaction of 4‐(1‐adamantyl)phenol and bis(3‐nitrophenyl)‐4‐fluorophenyl phosphine oxide, followed by reduction. The phenol group was prepared by the Friedel–Crafts reaction of 1‐bromoadamantane and phenol, whereas the phosphine oxide group was synthesized by the Grignard reaction of 1‐bromo‐4‐fluorobezene and diphenyl phosphinic chloride, followed by nitration. The monomer and its intermediate compounds were characterized with Fourier transform infrared, NMR, and melting‐point apparatus. The monomer was then used to prepare polyimides with 2,2‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride, 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride, 4,4′‐oxydiphthalic dianhydride, and pyromellitic dianhydride by the conventional two‐step synthesis: the preparation of poly(amic acid) followed by solution imidization. The molecular weights of the polyimides were controlled to 20,000 g/mol by off‐stoichiometry, and the synthesized polyimides were characterized with Fourier transform infrared, NMR, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry. In addition, the solubility, intrinsic viscosity, dielectric constant, and birefringence of the polyimides were evaluated. Novel polyimides with mDAATPPO exhibited good solubility, high glass‐transition temperatures (290–330 °C), excellent thermal stability (>500 °C), low dielectric constants (2.77–3.01), low refractive indices, and low birefringence values (0.0019–0.0030). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2567–2578, 2006  相似文献   

2.
Two novel 9,9‐difunctionalized fluorene‐type monomers, 9,9‐bis(4‐hydroxyphenyl‐ and 4‐aminophenyl)‐2,3:6,7‐dibenzofluorenes, are synthesized by the reaction of dibenzenzofluorenone with phenol and aniline. These monomers are used for the preparation of polyester and polyimide as the typical polymers to evaluate the property change such as thermal stability caused by the benzene rings fused to the fluorene skeleton with keeping good solubility, in comparison with the polymers derived from simple fluorenone. In fact, these two new polymers have the fairly enhanced thermal stability and refractive index value along with satisfactory solubility in organic solvents, enough to emphasize the fusion effect. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2602–2605  相似文献   

3.
A new triphenylamine‐containing aromatic diamine monomer, N,N‐bis(4‐aminophenyl)‐N,N′‐bis(4‐tert‐butylphenyl)‐1,4‐phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents. A novel family of electroactive polyamides with di‐tert‐butyl‐substituted N,N,N,N′‐tetraphenyl‐1,4‐phenylenediamine units were prepared via the phosphorylation polyamidation reactions of the newly synthesized diamine monomer with various aromatic or aliphatic dicarboxylic acids. All the polymers were amorphous with good solubility in many organic solvents, such as N‐methyl‐2‐pyrrolidinone (NMP) and N,N‐dimethylacetamide, and could be solution‐cast into tough and flexible polymer films. The polyamides derived from aromatic dicarboxylic acids had useful levels of thermal stability, with glass‐transition temperatures of 269–296 °C, 10% weight‐loss temperatures in excess of 544 °C, and char yields at 800 °C in nitrogen higher than 62%. The dilute solutions of these polyamides in NMP exhibited strong absorption bands centered at 316–342 nm and photoluminescence maxima around 362–465 nm in the violet‐blue region. The polyamides derived from aliphatic dicarboxylic acids were optically transparent in the visible region and fluoresced with a higher quantum yield compared with those derived from aromatic dicarboxylic acids. The hole‐transporting and electrochromic properties were examined by electrochemical and spectro‐electrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium‐tin oxide‐coated glass substrate exhibited two reversible oxidation redox couples at 0.57–0.60 V and 0.95–0.98 V versus Ag/AgCl in acetonitrile solution. The polyamide films revealed excellent elcterochemical and electrochromic stability, with a color change from a colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.2 V. These anodically coloring polymeric materials showed interesting electrochromic properties, such as high coloration efficiency (CE = 216 cm2/C for the green coloring) and high contrast ratio of optical transmittance change (ΔT%) up to 64% at 424 nm and 59% at 983 nm for the green coloration, and 90% at 778 nm for the blue coloration. The electroactivity of the polymer remains intact even after cycling 500 times between its neutral and fully oxidized states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2330–2343, 2009  相似文献   

4.
A benzoxazine ( P‐bapf ) based on 9,9‐bis(4‐aminophenyl)fluorene (BAPF), phenol, and formaldehyde was successfully prepared using two‐pot and one‐pot procedures. In the two‐pot approach, BAPF initially reacted with 2‐hydroxybenzaldehyde, leading to 9,9‐bis(4‐(2‐hydroxybenzylideneimino)phenyl)fluorene. The imine linkages of 9,9‐bis(4‐(2‐hydroxybenzylideneimino)phenyl)fluorene were then reduced by sodium borohydride, forming 9,9‐bis(4‐(2‐hydroxybenzylamino)phenyl)fluorene. Finally, paraformaldehyde was added to induce ring closure condensation, forming benzoxazine ( P‐bapf ). In the one‐pot approach, P‐bapf was obtained directly by reacting BAPF, phenol, and paraformaldehyde in various solvents. Among the solvents, we found that using toluene/ethanol (2/1, v/v) as a solvent leads to the best purity and yield. No gelation was observed in the preparation. The structure of the resulting benzoxazine was confirmed by 1H, 13C, 1H? 1H and 1H? 13C NMR spectra. P‐bapf exhibits a photoluminescent emission at 395 nm under an excitation of 275 nm. After curing, the resulting P‐bapf thermoset exhibits Tg as high as 236 °C, and the Tg can be further increased to 260 °C by copolymerization with an equal equivalent of cresol novolac epoxy. The 5% degradation temperature of the P‐bapf thermoset reaches as high as 413 °C (N2) and 431 °C (air). The refractive index at 589 nm is as high as 1.70, demonstrating a high refractive index characteristic of fluorene linkage. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

5.
Improved reaction conditions for the preparation of poly(p‐phenylene sulfide) (PPS) directly from bis(4‐bromophenyl) disulfide (BBD) have been established. Heating BBD with magnesium metal afforded only a low molecular weight polymer. PPS with a melting temperature around 280 °C was obtained from BBD in the presence of sodium carbonate or zinc metal. The best results were obtained with the addition of a catalytic amount of KI to the zinc–BBD mixture. Polymers prepared by the above methods are semicrystalline and dissolve in 1‐chloronaphthalene and have properties comparable to commercial PPS. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 900–904, 2006  相似文献   

6.
The title compounds, C18H21NO and C18H21NS, in their enantiomerically pure forms are isostructural with the enantiomerically pure 4‐(4‐hydroxyphenyl)‐2,2,4‐trimethylchroman and 4‐(2,4‐dihydroxyphenyl)‐2,2,4‐trimethylchroman analogues and form extended linear chains via N—H...O or N—H...S hydrogen bonding along the [100] direction. The absolute configuration for both compounds was determined by anomalous dispersion methods with reference to both the Flack parameter and, for the light‐atom compound, Bayesian statistics on Bijvoet differences.  相似文献   

7.
The Zn center in [ZnCl2(L‐S‐S‐L)], where L‐S‐S‐L = bis(1‐methylimidazole‐2)disulfide, adopts a tetrahedral configuration defined by two Cl atoms and two N atoms from L‐S‐S‐L, which was obtained by in situ oxidation of 1‐methylimidazole‐2‐thione. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

8.
A new one‐dimensional coordination polymer, catena‐poly[[acetatohexaaqua{μ4‐2,6‐bis[bis(carboxylatomethyl)aminomethyl]‐4‐methylphenolato}trizinc(II)] octahydrate], [Zn3(C17H17N2O9)(C2H3O2)(H2O)6]·8H2O, is a trinuclear complex consisting of three zinc centers joined by a phenolate bridge and Zn(H2O)4 units. In each complex polymer unit, the three Zn atoms have different coordination modes. Of the two phenolate‐bridged Zn ions, one adopts a distorted octahedral coordination composed of two carboxylate ligands, one tertiary N atom, two water molecules and the bridging phenolate ligand, while the other adopts a pyramidal geometry composed of two carboxylate ligands, one tertiary N atom from another coordination arm, one acetate anion as the counter‐anion and the bridging phenolate ligand. The third type of Zn centre is represented by two independent Zn atoms lying on inversion centres. They both have an octahedral coordination consisting of four O atoms from four water molecules and two acetate carbonyl O atoms from the ligand. The latter Zn atoms join the above‐mentioned binuclear complex units through O atoms of the carboxylate groups into an infinite chain. Neighboring aromatic rings are distributed above and below the chain in an alternating manner. Between the coordination chains, the Zn...Zn separations are 5.750 (4) and 6.806 (4) Å. The whole structure is stabilized by hydrogen bonds formed mainly by solvent water molecules.  相似文献   

9.
The new high‐spin iron(II) complex, [Fe(C12H10N6)2(H2O)2](C8H3N4S)2 or [Fe(abpt)2(H2O)2](tcnsme)2 [where abpt is 4‐amino‐3,5‐di‐2‐pyridyl‐4H‐1,2,4‐triazole and tcnsme is the 1,1,3,3‐tetracyano‐2‐methylthiopropenide anion], consists of discrete [Fe(abpt)2(H2O)2]2+ dications, where the FeII ion is coordinated by two N,N′‐bidentate chelating abpt ligands in the equatorial plane and two water molecules in trans positions, generating a distorted octahedral [FeN4O2] environment. The cationic unit is neutralized by two polynitrile tcnsme anions, in which the C—N, C—C and C—S bond lengths indicate extensive electronic delocalization. In the crystal structure, the dications and anions are linked through O—H...N and N—H...N hydrogen bonds involving the water H atoms and those of the NH2 groups and the N atoms of the CN groups, leading to the formation of a three‐dimensional network.  相似文献   

10.
Dapsone, formerly used to treat leprosy, now has wider therapeutic applications. As is the case for many therapeutic agents, low aqueous solubility and high toxicity are the main problems associated with its use. Derivatization of its amino groups has been widely explored but shows no significant therapeutic improvements. Cocrystals have been prepared to understand not only its structural properties, but also its solubility and dissolution rate. Few salts of dapsone have been described. The title salts, C12H13N2O2S+·C6H5O3S·H2O and C12H13N2O2S+·CH3SO3·H2O, crystallize as hydrates and both compounds exhibit the same space group (monoclinic, P21/n). The asymmetric unit of each salt consists of a 4‐[(4‐aminophenyl)sulfonyl]anilinium monocation, the corresponding sulfonate anion and a water molecule. The cation, anion and water molecule form hydrogen‐bonded networks through N—H…O=S, N—H…Owater and Owater—H…O=S hydrogen bonds. For both salts, the water molecules interact with one sulfonate anion and two anilinium cations. The benzenesulfonate salt forms a two‐dimensional network, while the hydrogen bonding within the methanesulfonate salt results in a three‐dimensional network.  相似文献   

11.
The trisilanol 1,3,5‐(HOi‐Bu2Si)3C6H3 ( 7 ), prepared in three steps from 1,3,5‐tribromobenzene via the intermediates 1,3,5‐(Hi‐Bu2Si)3C6H3 ( 8 ) and 1,3,5‐(Cli‐Bu2Si)3C6H3 ( 9 ) forms an equimolar complex with trans‐bis(4‐pyridyl)ethylene (bpe), 7 ·bpe, whose structure was investigated by X‐ray crystallography. The hydrogen‐bonded network features a number of SiO? H(H)Si and SiO? H hydrogen bridges. Evidence was found for cooperative strengthening within the sequential hydrogen bonds. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

12.
The dimeric and centrosymmetric structure of [Zn(S2CNEt2)2(trans‐NC5H4C(H)?C(H)C5H4N)]2 shows bidentate coordination by the dithiocarbamate ligands and a distorted square pyramidal geometry for zinc, defined by a NS4 donor set with the N atom in the apical position. The compound co‐crystallises with a centrosymmetric molecule of trans‐NC5H4C(H)?C(H)C5H4N that does not form a significant interaction to the Zn atom. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

13.
In the title compound, C20H16Cl2O4S2, the mol­ecules lie across centres of inversion. A single type of intermolecular C—H?O hydrogen bond, with a C?O distance of 3.254 (3) Å and a C—H?O angle of 132°, links the mol­ecules into ladders whose uprights form C(6) chains and whose rungs enclose centrosymmetric R(22) rings.  相似文献   

14.
The title compound, [Cd3(C8H10O4)3(C12H9N3)2(H2O)2]n or [Cd3(chdc)3(4‐PyBIm)2(H2O)2]n, was synthesized hydrothermally from the reaction of Cd(CH3COO)2·2H2O with 2‐(pyridin‐4‐yl)‐1H‐benzimidazole (4‐PyBIm) and cyclohexane‐1,4‐dicarboxylic acid (1,4‐chdcH2). The asymmetric unit consists of one and a half CdII cations, one 4‐PyBIm ligand, one and a half 1,4‐chdc2− ligands and one coordinated water molecule. The central CdII cation, located on an inversion centre, is coordinated by six carboxylate O atoms from six 1,4‐chdc2− ligands to complete an elongated octahedral coordination geometry. The two terminal rotationally symmetric CdII cations each exhibits a distorted pentagonal–bipyramidal geometry, coordinated by one N atom from 4‐PyBIm, five O atoms from three 1,4‐chdc2− ligands and one O atom from an aqua ligand. The 1,4‐chdc2− ligands possess two conformations, i.e.e,etrans‐chdc2− and e,acis‐chdc2−. The cis‐1,4‐chdc2− ligands bridge the CdII cations to form a trinuclear {Cd3}‐based chain along the b axis, while the trans‐1,4‐chdc2− ligands further link adjacent one‐dimensional chains to construct an interesting two‐dimensional network.  相似文献   

15.
A regiospecific cyclization‐dehydration reaction of a 1‐[(4‐(N‐alkyl‐N‐(tert‐butyloxycarbony)amino)‐phenyl]‐4,4,4‐trifluorobutane‐1,3‐done with a 4‐aminosulfonyl‐, or 4‐methylsulfonyl‐, phenylhydrazine hydrochloride in refluxing ethanol proceeded with simultaneous loss of the N‐tert‐butyloxycarbonyl protecting group to afford a group of 1‐(4‐methanesulfonylphenyl or 4‐aminosulfonylphenyl)‐5‐[4‐(N‐alkylaminophenyl)]‐3‐(trifluoromethyl)‐11H‐pyrazoles(6). Subsequent reaction of the pyrazole 6 (R1 = R2 = Me) with nitric oxide (40 psi) proceeded via a N‐methylamino‐N‐diazen‐1‐ium‐1,2‐diolate intermediate that undergoes protonation of the more basic diazen‐1‐ium‐1,2‐diolate N2‐nitrogen and then loss of a nitroxyl (HNO) species to furnish the N‐nitroso product 7.  相似文献   

16.
Levulinic acid derivatives are potential `green chemistry' renewably sourced molecules with utility in industrial coatings applications. Suitable single crystals of the centrosymmetric title compounds, C14H22O6 and C16H26O6, respectively, were obtained with difficulty. The data for the latter hexane‐1,6‐diyl compound were extracted from the major fragment of a three‐component twinned crystal. Both compounds crystallize in similar‐sized unit cells with identical symmetry, utilizing the same weak nonconventional attractive C—H...O(ketone) hydrogen bonds via C(4) and C(5) motifs, which expand to R22(30) ring and C22(14) chain motifs. Their different packing orientations in similar‐sized unit cells suggest that crystal growth involving packing mixes could lead to intergrowths or twins.  相似文献   

17.
A series of aromatic polyimides (PIs) containing pyridazine or pyrimidine in their main chains has been developed. All of the PIs were prepared from newly synthesized diamines, 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine (APP), 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine (APPM) and aromatic dianhydrides, 4,4′‐[p‐thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA) and 4,4′‐oxydiphthalic anhydride (ODPA) via the conventional two‐step polycondensation. The PIs showed good thermal stability with 10% weight loss at temperatures above 450 °C and glass transition temperatures above 190 °C. Films with a 10‐μm thickness exhibited good optical transparency above 80% at 500 nm, high refractive indices ranging from 1.7218 to 1.7499, and low birefringence between 0.0066 and 0.0102. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4886–4984, 2009  相似文献   

18.
The isomeric diamine monomer 5(6)‐amino‐1‐(4‐aminophenyl)‐1,3,3‐trimethylindane (DAPI) was successfully synthesized via the dimerization of α‐methylstyrene followed by nitration and reduction. High molecular weight, soluble polyimides were synthesized via ester–acid solution imidization techniques and had glass‐transition temperature values ranging from 247 to 369 °C. The polymers were soluble in common organic solvents because of the asymmetric and nonplanar nature of DAPI and displayed good short‐term thermal stability by thermogravimetric analysis, as shown by their 5% weight‐loss values above 500 °C in air. The DAPI/(3,4‐dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) polyimide also showed 2‐h thermal stability at 400 °C under nitrogen, despite the partial aliphatic character. Refractive index values as low as 1.571 were observed for DAPI/6FDA, which allows an estimated dielectric constant of 2.47 to be derived. The permeation of O2 and N2 was conducted on thin dense films. The bulky, bent, and isomeric nature of DAPI imparted film‐forming membranes that permitted high O2 permeability. In combination with 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA), DAPI had a good combination of O2 permeability and O2/N2 selectivity values of 2.8 Ba and 7.3, respectively. The polymerization method utilized to facilitate the cyclization of DAPI/BTDA to the polyimide affected the final thermal properties of the resulting polymer. The chemical imidization of DAPI/BTDA generated a polyimide with a glass‐transition temperature value of 311 °C and a 5% weight‐loss value in air of 457 °C. However, thermal and ester–acid imidization routes yielded an increase in the thermal properties. The ester–acid solution imidization of DAPI/BTDA produced a polymer glass‐transition temperature value of 333 °C and a 5% weight‐loss value of 525 °C in air. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2840–2854, 2000  相似文献   

19.
The asymmetric unit of {[4,7‐bis(2‐amino­ethyl)‐1,4,7‐tri­aza­cyclo­nonan‐1‐yl]acetato}zinc(II) triaqua{μ‐[4,7‐bis(2‐amino­ethyl)‐1,4,7‐tri­aza­cyclo­nonan‐1‐yl]acetato}lithium(I)zinc(II) chloride diperchlorate, [Zn(C12H26N5O2)][LiZn(C12H26N5O2)(H2O)3]Cl(ClO4)2, obtained from the reaction between the lithium salt of 4,7‐bis(2‐amino­ethyl)‐1,4,7‐tri­aza­cyclo­nonane‐1‐acetate and Zn(ClO4)2, contains two ZnII complexes in which each ZnII ion is six‐coordinated by five N‐atom donors and one O‐­atom donor from the ligand. One carboxyl­ate O‐atom donor is not involved in coordination to a ZnII atom, but coordinates to an Li+ ion, the tetrahedral geometry of Li+ being completed by three water mol­ecules. The two complexes are linked via a hydrogen bond between a primary amine N—H group and the carboxyl­ate‐O atom not involved in coordination to a metal.  相似文献   

20.
A UV‐responsive polymer was prepared via condensation polymerization of 2‐nitrobenzyl(4‐(1,2‐dihydroxyethyl)phenyl)carbamate and azalaic acid dichloride. When the polymer was irradiated with UV light, the nitrobenzyl urethane protecting group was removed and the deprotected aniline underwent spontaneous 1,6‐elimination reactions, resulting in degradation of the polymer. Nanoparticles with encapsulated Nile Red were formulated with the degradable polymer and triggered burst release of Nile Red was observed when the nanoparticles were irradiated by UV light. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1161–1168  相似文献   

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