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1.
The condensation reaction between tetraaza[14]annulene ( 1 ) and a series of para-substituted benzoyl chlorides led to the 16-benzoylated corresponding products in 13–21% yields, but 1 was unreactive with alkyl acid chlorides and easily cleaved in macrocyclic framework. The mass spectra show the presence of molecular ion peaks which support the 16-benzoylated products. A strong ir band due to the C = N stretching mode of the macrocyclic moiety was observed at 1610 cm?1 and shifted slightly toward higher energy upon benzoylation. An intense ir band which was associated with a C = 0 stretching mode was newly observed at 1640 cm1. The very strong absorption band about 29000 cm?1 was attributed to the π ? π* transition and gave a slight shift to higher frequency on benzoylation. All proton signals except for methyl protons exhibit downfield shifts due to the deshielding effect of the substituted benzene ring, but the methyl proton peaks show upfield shifts due to the shielding effect caused by the magnetic anisotropy of the substituted benzene ring. The 13C nmr result is also in accord with that of 1H nmr.  相似文献   

2.
1,4‐Bis(vinyldiphenylsilyl)benzene ( I ) has been prepared and copolymerized by Pt‐catalyzed hydrosilylation with 1,9‐dihydridodecamethylpentasiloxane ( II ), 3,5,7‐tris(3′,3′,3′‐trifluoropropyl)‐1,1,3,5,7,9,9‐heptamethylpentasiloxane ( III ) and two different α,ω‐bis(hydrido)polydimethylsiloxanes (PDMS). The monomers and polymers were fully characterized by IR, UV, 1H, 13C, 19F, and 29Si‐NMR spectroscopy. The starting PDMS polymers and the product copolymers were further characterized by GPC, DSC, and TGA. The polymers showed thermal transitions characteristic to thermoplastic elastomers. The 1,4‐bis(ethyldiphenylsilyl)benzene moieties displayed melting transitions above room temperature while copolymer glass transition temperatures were below room temperature. Fluorescence spectra and quantum efficiencies of I and copolymers have been determined. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4825–4831, 2006  相似文献   

3.
Hexadehydro[12]annulenes annelated with one or two TTF units have been synthesized to investigate their pi-amphoteric properties based on the TTF and [12]annulene moieties; these compounds show multi-redox potentials, solvatochromism and the formation of large sandwich complexes.  相似文献   

4.
We report the synthesis and characterization of a series of novel mesogen‐jacketed liquid‐crystalline polymers, poly[2,5‐bis(4′‐alkoxycarbonylphenyl)styrene]s ( 1‐m , where m is the number of carbon atoms in the alkyl tails), along with the corresponding monomers, 2,5‐bis(4′‐alkoxycarbonylphenyl)styrenes ( 2‐m ), and their precursors, 2,5‐bis(4′‐alkoxycarbonylphenyl)toluenes ( 3‐m ). The influence of the tail length on the thermotropic properties of the two types of low‐molecular‐mass compounds and macromolecules was investigated with a combination of differential scanning calorimetry, polarized optical microscopy, and wide‐angle X‐ray diffraction techniques. Except for compound 3‐3 , which exhibited a monotropic nematic phase, all members of the low‐molar‐mass molecules developed no mesophase during both heating and cooling processes. The glass‐transition temperatures of the polymers decreased as the tail lengths increased. The 5% weight loss temperatures of all the polymers under a nitrogen atmosphere were above 360 °C, indicating quite high thermal stability. Although polymers 1‐1 and 1‐2 were non‐liquid‐crystalline, columnar nematic phases were observed for the remaining homopolymers with longer alkyl tails. The mesophases of 1‐3 to 1‐9 that developed at high temperatures remained upon cooling to room temperature, whereas those of 1‐10 to 1‐12 disappeared during the cooling process. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 830–847, 2007.  相似文献   

5.
2,2‐Bis[4(4‐aminophenoxy)phenyl]phthalein‐3′,5′‐bis(trifluoromethyl)anilide (6FADAP), containing fluorine and phthalimide moieties, was synthesized via the Williamson ether condensation reaction from 1‐chloro‐4‐nitrobenzene and phenolphthalein‐3′,5′‐bis(trifluoromethyl)anilide, which was followed by hydrogenation. Monomers such as 2,2‐bis[4(4‐aminophenoxy)phenyl]phthalein‐anilide containing phthalimide groups and 2,2‐bis[4(4‐aminophenoxy)phenyl]phthalein containing only phthalein moieties were also synthesized for comparison. The monomers were first characterized by Fourier transform infrared (FTIR), 1H NMR, 19F NMR, elemental analysis, and titration and were then used to prepare polyimides with 2,2‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride. The polyimides were designed to have molecular weights of 20,000 g/mol via off‐stoichiometry and were characterized by FTIR, NMR, gel permeation chromatography (GPC), differential scanning calorimetry, and thermogravimetric analysis. Their solubility, water absorption, dielectric constant, and refractive index were also evaluated. The polyimides prepared with 6FADAP, containing fluorine and phthalimide moieties, had excellent solubility in N‐methylpyrrolidinone, N,N‐dimethylacetamide, tetrahydrofuran, CHCl3, tetrachloroethane, and acetone, and GPC analysis showed a molecular weight of 18,700 g/mol. The polyimides also exhibited a high glass‐transition temperature (290 °C), good thermal stability (~500 °C in air), low water absorption (1.9 wt %), a low dielectric constant (2.81), a low refractive index, and low birefringence (0.0041). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3361–3374, 2003  相似文献   

6.
A new copolymer of benzo[1,2‐b:4,5‐b′]dithiophene and 3,3′‐bis(tridecanoxy)‐5,5′‐bithiophene was synthesized through Stille copolymerization. The bis‐(3‐alkoxythiophene) monomer was synthesized through a silver fluoride mediated, palladium‐catalyzed cross‐coupling, in which bromide functional groups were preserved instead of consumed. The copolymer has been characterized and applied in field‐effect transistors, giving a hole mobility of 2 × 10?3 cm2/Vs and an on/off ratio >106, with negligible hysteresis, on standard silicon substrates. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1973–1978, 2010  相似文献   

7.
The title compounds, C14H12Br2Se2, (I), C14H12Cl2Se2, (II), and C14H14O2Se2, (III), feature a diselenide bridge between two o‐benzyl bromide [in (I)], two o‐benzyl chloride [in (II)] or two o‐benzyl alcohol units [in (III)]. In the molecular structure of (I) and in both independent molecules of (II), close contacts are observed between the halogen centres and the diselenide unit. In the case of modification (IIIa), strong hydrogen bonds between the –OH groups dominate, whereas the molecular structures of modification (IIIb) and bis{2‐[(dimethylamino)methyl]phenyl} diselenide, C18H24N2Se2, (IV), are comparable with those of (I) and (II). A correlation between the strength of the contacts and the angle between the benzene planes and the Se—Se units is found.  相似文献   

8.
A novel trifluoromethylaryl‐substituted disilanol, bis[(2‐trifluoromethyl)phenyl] silanediol, was prepared by hydrolysis of the precursor dichloride and fully characterized. Single‐crystal X‐ray diffraction indicates doubly linked hydrogen bonded dimers and also hydrogen bonding to tetrahydrofuran solvent. The acidity of the silanol functions is enhanced by the presence of the trifluoromethyl groups and the compound is found to be active in promoting a standard Diels–Alder reaction, increasing yields by a factor of three.  相似文献   

9.
7,16-Dialkyl-5,14-dihydrodibenzo[b,i][1,4,8,11]tetraza[14]annulenes have been synthesized from o-phenylenediamine and 2-alkyl-3-trimethyl-siloxyacroleins. The probable mechanism is discussed. It is shown that metallo complexes of 7,16-dialkyldibenzotetraaza[14]annulenes have been prepared in high yield under template conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1400–1403, October, 1992.  相似文献   

10.
In the title compound, [Zr(C16H13P)Cl2], the geometry at the metal atom is distorted tetrahedral; the Cl—Zr—Cl angle is 101.490 (16)° and the cyclopentadienyl (Cp) centroids subtend an angle of 122.63 (3)° at the Zr atom. The P atom lies 0.474 (3) and 0.496 (3) Å out of the planes of the Cp rings. The C—P—C angle of 91.42 (7)° reflects the pincer effect of the two Cp rings. Three C—H...Cl, one C—H...P, one C—H...π and one Cl...P interaction link the molecules to form thick layers parallel to the bc plane.  相似文献   

11.
In this study, the sandwich complex of tmtaa, Y(tmtaa) (Htmtaa)·2THF (H2tmtaa=6,8,15,17-tetramethyldibenzo [b,i] , respectively. The distances of the yttrium to the planes of the 4 nitrogen atoms for tmtaa and Htmtaa are 1.44 (2) and 1.51 (2) Å, respectively.  相似文献   

12.
1,4‐Bis(4‐alkylpyridinium)butadiyne triflate ( 2a and 2b ) that was prepared by the reaction of 1,4‐bis(4‐pyridyl)butadiyne ( 1 ) with alkyl trifluoro‐methanesulfonate, was found to grow into a large crystal as a result of the quaternized structure. The thermal treatment of 2a and 2b gave rise to 1,4‐addition polymerization to yield the polydiacetylene. The third‐order nonlinear optical susceptibility [χ(3)] of the polymer was determined by the femto‐second Z‐scan method to exhibit the remarkable high value of 1.1 × 10?11 esu at 650 nm. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3686–3691, 2001  相似文献   

13.
7H‐Dibenzo[a,g]carbazole‐substituted polysiloxane (PSX‐[a,g]BCz) has been synthesized by hexachloroplatinate (IV) hydrate polymerization from poly(methylhydrosiloxane) and 7‐ally‐7H‐dibenzo[a,g]carbazole. PSX‐[a,g]BCz composite showed large orientational birefringences because of both large dipole moments and high‐polarizability anisotropies of P‐IP‐DC chromophore associated with the effective conjugation along the polyene. The 50‐μm thick photorefractive material containing 30 wt % 2‐[3‐[(E)‐2(piperidino)‐1‐ethenyl]‐5,5‐dimethyl]‐2‐cyclohexenyliden]malononitrile showed a diffraction efficiency of 51% at 55 V/μm, which corresponded to a Δn of 3.45 × 10?3. PSX‐[a,g]BCz composite shows a fast time constant of 0.42 s at 34 °C and 55 V/μm, which corresponded to the space‐charge field of 12 V/μm under 70 V/μm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1783–1791, 2008  相似文献   

14.
The crystal structures of the title compounds, (C24H20P)2[Ni(C6H6O4S2)2], (I), and (C24H20P)2[Ni(C6H6O4S2)2]I, (II), in the diamagnetic reduced (2–) and paramagnetic oxidized (1–) states, are reported at 200 and 293 K, respectively. In both compounds, the Ni atom lies on an inversion centre and the NiS4 coordination is thus required to be exactly planar. In the diamagnetic complex, (I), the Ni—S distances are 2.1818 (7) and 2.1805 (6) Å, while they are 2.1481 (6) and 2.1392 (5) Å in the paramagnetic complex, (II). This results from both the different complex core oxidation states and the different conformations of the methoxycarbonyl groups.  相似文献   

15.
The preparation of novel alkyl monobridged 2,4‐dimethyl‐5‐amino‐benzo[b][1,8]naphthyiridine and benzo[b][1,8]naphthyridone derivatives by phase transfer catalysis is reported.  相似文献   

16.
A series of new soluble poly(amide‐imide)s were prepared from the diimide‐dicarboxylic acid 2,2‐bis[4‐(4‐trimellitimidophenoxy)phenyl]hexafluoropropane with various diamines by direct polycondensation in N‐methyl‐2‐pyrrolidinone containing CaCl2 with triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.52–0.86 dL · g?1. The poly(amide‐imide)s showed an amorphous nature and were readily soluble in various solvents, such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, and cyclohexanone. Tough and flexible films were obtained through casting from DMAc solutions. These polymer films had tensile strengths of 71–107 MPa and a tensile modulus range of 1.6–2.7 GPa. The glass‐transition temperatures of the polymers were determined by a differential scanning calorimetry method, and they ranged from 242 to 279 °C. These polymers were fairly stable up to a temperature around or above 400 °C, and they lost 10% of their weight from 480 to 536 °C and 486 to 537 °C in nitrogen and air, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3498–3504, 2001  相似文献   

17.
5,10,15,20‐Tetrakis[4‐(triorganostannyloxy)phenyl]porphyrins, (R3SnO)4TPP [2, R = Cy (a), Ph (b), PhC(CH3)2CH2 (c)], have been synthesized by the condensation of 4‐(triorganostannyloxy)benzaldehyde, 4‐(R3SnO)C6H4CHO (1), with pyrrole in the presence of BF3 followed by oxidation by p‐chloranil and characterized by means of elemental analysis, IR, UV–visible and NMR (1H, 13C and 119Sn) spectra. The results of X‐ray single‐crystal diffraction show that 1a and 1b possess a trans‐C3SnO2 trigonal bipyramidal geometry with the axial positions occupied by the phenolate oxygen and formyl group oxygen of an adjacent molecule and form a one‐dimensional zigzag chain. In 2a, the macrocyclic core of the porphyrin is coplanar and each tin atom possesses a distorted tetrahedral geometry. These compounds (1 and 2) have potent in vitro cytotoxic activity against two human tumor cell lines – CoLo205 and MCF‐7 – and the activity decreases in the order Ph > Cy > PhC(CH3)2CH2 for the R group bound to tin. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
19.
In both title compounds, C18H24N2O2, (Ia), and C18H26N2O22+·2ClO4, (II), respectively, the two aryl rings are strictly parallel, with an inversion centre lying at the mid‐point of each central CH2—CH2 bond. Molecules in (Ia) are linked into two‐dimensional layers by N—H...O hydrogen bonds. The component ions in (II) are joined together by a combination of N/O/C—H...O hydrogen bonds and C—H...π and anion...π interactions, forming a three‐dimensional network. A structural understanding of (Ia) and (II) may provide some useful information about how and why their metal–organic complexes display various biological activities and function in catalytic processes.  相似文献   

20.
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