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1.
The syntheses of poly(methylsiloxane)s containing 4-[S(-)-L-methyl-1 -butoxy] -4′-[p-(ω -alkan -1 -yloxy)benzoyloxy] -a-methylstilbene side groups containing 11-undecanyl (18), 8-octyl (19), 6-hexyl (20), and 3-propyl (21), of a poly[(50-55%)-methyl-co-(45-50%)-dimethylsiloxane] containing 4-[S(-)-2-methyl-1-butoxy]-4′-[p-(8-octan-1-yloxy)benzoyloxy]-α-methylstilbene side groups (22) and of a poly(methylsiloxane) containing a 1:1 molar ratio of 4-[S(-)-2-methyl-1 -butoxyl]-4′ -[p-(8-octan-1 -yloxy)benzoyloxy] -α-methylstilbene and 4-[S(-)-2-methyl-l -butoxyl-4′ -[p-(6-hexan-1-yloxy)-benzoyloxyl-α-methylstilbene side groups (23) are described. All polymers and copolymers were characterized by a combination of differential scanning calorimetry and thermal optical polarized microscopy techniques. 18 exhibits an enantiotropic S A, while 19, 20, 21, and 23 display both enantiotropic s A and S*c mesophases. 22 exhibits only an enantiotropic s: mesophase. In addition, all polymers and copolymers exhibit sidechain crystallization. These results have demonstrated that extending the length of the rigid part of the mesogenic unit of 4-[S(-)-2-methyl-l-butoxy]-4′-(ω-alkan-l-yloxy)-α-methylstilbene to 4-[S(-)-2-methyl-l-butoxy]-4′ -[p-(ω-alkan-l -yloxy)benzoyloxy]-α-methylstilbene increases the tendency of the resulting poly(methylsiloxane)s toward polymesomorphism.  相似文献   

2.
Abstract

Radical homopolymerization of N-[4-N′-(α-methylbenzyl)-aminocarbonylphenyl]maleimide ((S)-MBCP) was carried out at 50 and 70°C for 24 h to give optically active polymers ([α]25 D = 159.8 to 163.4°). Radical copolymerizations of (S)-MBCP (M1) were performed with styrene (ST, M2, methyl methacrylate (MMA, M2) in THF at 50°C. The monomer reactivity ratios (r 1, r 2) and the Alfrey-Price Q, e values were determined as follows: r 1 = 0.32, r 2= 0.14, Q 1 = 1.74, e 1 = 0.96 in the (S)-MBCP-ST system; r 1 = 0.54, r 2 = 0.93, Q 1 = 1.11, e 1 = 1.23 in the (S)-MBCP-MMA system. Chiroptical properties of the polymers and the copolymers were also investigated, and asymmetric induction into the copolymer main chain is discussed.  相似文献   

3.
Two novel cyclotriphosphazene derivatives containing 6-(4-hydroxyphenyl)-2,2'-bipyridine(hopbp)side groups,N_3P_3(dobp)_2(hopbp)_2(1)and N_3P_3(dobp)(hopbp)_4(2)(dobp=2,2'-dioxybiphenyl),were synthesized and characterized.These compounds display strong fluorescent emission both in solution and in solid state.Their absorption and emission spectra are sensitive to proton:the addition of HBF4 to the methanol and dichloromethane solution(9∶1,volume ratio)of compound 1 led to a red-shift from 350 to 460 nm for the emission spectrum,and the process was also characterized by isosbestic points of absorption spectra at 267,287 and 313 nm.  相似文献   

4.
SynthesisandCharacterizationoftheSideChainLiquidCrystallinePoly(monoester{6-[4-(p-nitrophenuyl)azo]phenoxy-1-hexyloxy}ofMalei...  相似文献   

5.
Shao  Yin  ZHANG  Xi  Gao  JIAN 《中国化学快报》2003,14(2):145-146
A new monomer of 4,4′-biphenyl-bis[4-phthalazin-1(2H)-one] was synthesized from biphenly and phthalic anhydride,and a novel copoly(aryl ether ketone)(PPEK) was synthesized from 2,2-bis(4-hydroxyphenyl)-propane(BPA),4,4′-biphenyl-bis-[4-phthalazin-1(2H)pne],4,4′-difluorodiphenylketone(DFK).The monomer and copolymer were characterized by FT-IR and ^1H-NMR.DSC and TGA were used to the novel polymer.  相似文献   

6.
Poly(aryl ether ketone)s are a category of high performance engineering thermoplastics characterized by high glass transition temperature and excellent thermooxidative stability. And they have important applications in electronic, electric, aircraft and aerospace industries1~3. Considerable efforts have been made towards the improvement of solubility or processability of poly(aryl ether ketone)s4,5. In our work, a novel bis(phthalazinone) monomer 1 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] …  相似文献   

7.
2-(1′-Methyl-2′-pyrrolyl)-1H-phenanthro[9,10-d]imidazole was synthesized by heating 9,10-phenanthrenequinone and 1-methyl-2-pyrrolecarboxaldehyde in glacial acetic acid in the presence of ammonium acetate. The reactions of electrophilic substitution (nitration, bromination, sulfonation, formylation, acylation) were studied for the product of its N-methylation in the KOH-DMSO medium. The electrophilic attack was found to affect exclusively the pyrrole ring.  相似文献   

8.
9.
Two novel cyclotriphosphazene derivatives containing 6- (4-hydroxyphenyl)-2,2′-bipyridine (hopbp) side groups, N3 P3 (dobp) 2 (hopbp) 2 ( 1 ) and N3 P3 (dobp) (hopbp) 4 (2) ( dobp = 2,2′-dioxybiphenyl), were synthesized and characterized. These compounds display strong fluorescent emission both in solution and in solid state. Their absorption and emission spectra are sensitive to proton: the addition of HBF4 to the methanol and dichloromethane solution(9: 1, volume ratio) of compound 1 led to a red-shift from 350 to 460 nm for the emission spectrum, and the process was also characterized by isosbestic points of absorption spectra at 267, 287 and 313 nm.  相似文献   

10.
Aromatic polyimides are distinguished for their excellent mechanical and thermal properties in many engineering fields1. However, aromatic polyimides are normally insoluble in common organic solvents, which restricts their applications in some fields. Many efforts have been taken to improve their solubility. Introducing bulky side groups and non-coplanar structure into polymers bone chains is a good way to obtain the polymers with excellent mechanical and thermal properties2. In this paper…  相似文献   

11.
IntroductionHeterocyclicpolymersareaclassofpolymersthatusuallyshowexcellentthermalstabilityandhavereceivedconsiderableattentionashigh-modulusplastics.Theycanbesynthesizedbythereactionofheterocyclichandesoractivatedarylhandeswithahis(phenolate)anioninanucleophilicdisplacementreaction.Manydifferenttypesofhightemperatureheterocyclicpolymers,suchaspoly(etherimide)s,poly(aryletherbenzoxazole)s,poly(etherketone)shavebeensynthesizedbythismethodl-3.Inthispaper,anovelpoly(ethersulfoneketone)withC-Nbon…  相似文献   

12.
Biphenyl tetrazole ring is an important component of the Sartan family of novel drugs. 4′-Bromomethyl-2-(N-trityl-1H-tetrazol-5-yl)biphenyl was synthesized in this article from 4′-methyl-2-cyano-biphenyl through three steps. 4′-Methyl-2-cyano-biphenyl was reacted with azide ions with the help of ammonium chloride as catalyst in an autoclave with high conversion to afford the tetrazole compounds in 70.6% yield. After being protected by the trityl group with 92.6% yield, 4′-methyl-2-(N-trityl-1H-tetrazol-5-yl) biphenyl was brominated with N-bromosuccinimide (NBS) in cyclohexane with 2,2′-azo-isobutyronitrile (AIBN) acting as an initiator to provide the title compound in 83.8% yield.  相似文献   

13.
IntroductionTheiododemetalation[1]oftheproductsofthereactionsbetweentriphenyltinhydrideandethynyl(hydroxy)steroids[2,3]yields...  相似文献   

14.
A new ion-pair complex, [BrBzMeQl][Ni(mnt)2] (1) ([BrBzMeQl]+?=?1-(4′-bromobenzyl)-2-methylquinolinium; mnt2??=?maleonitriledithiolate), has been prepared and characterized. X-ray diffraction analysis shows that the Ni(mnt)2 anion and [BrBzMeQl]+ cations of 1 form completely segregated stacking columns, with the Ni?···?Ni distances alternating between 3.717 and 4.466?Å?in the Ni(mnt)2 stacking column. The variable-temperature magnetic susceptibilities of 1 have been measured over the range 75–300?K and the results reveal that the complex exhibits antiferromagnetic behavior.  相似文献   

15.
The title compound (C26H20ClN3O3) has been synthesized by 1,3-dipolar cycloaddition reaction from isatin, sarcosine and (Z)-4-(4-chlorobenzylidene)-2-phenyloxazol-5(4H)-one through a one-pot procedure, and its structure was confirmed by IR, 1H NMR, elemental analysis and single-crystal X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1, with a = 9.3903(19), b = 11.398(2), c = 12.603(3) , α = 83.495(3), β = 68.988(3), γ = 67.178(3)°, V = 1160.1(4) 3, Z = 2, Mr = 457.90, Dc = 1.311 g/cm3, μ = 0.198 mm-1, F(000) = 476, the final R = 0.0489 and wR = 0.1144 for 3109 observed reflections with I > 2σ(I).  相似文献   

16.
《Tetrahedron: Asymmetry》2001,12(15):2099-2102
A synthesis of the enamine (−)-(1′S)-5-ethyl-1-(1′-phenylethyl)-1,2,3,4-tetrahydropyridine 4 and its application in a synthesis of (−)-(1′S,4aS,8aR)- and (+)-(1′S,4aR,8aS)-4a-ethyl-1-(1′-phenylethyl)-octahydroquinolin-7-ones 5 and 6 is described. In addition, an X-ray study of 6 is reported. Finally, the preparation of (+)-(4aS,8aR)-4a-ethyl-octahydroquinolin-7-one 7 is described.  相似文献   

17.
Abstract

A new methacrylamide monomer, 4‐methacrylamidophenyl‐2′,3′‐benzostyryl ketone (MPBSK) having a free‐radical polymerizable group and a photocrosslinkable functional group, was synthesized by reacting 4‐(2′,3′‐benzocinnamoyl)aniline with methacryloyl chloride in the presence of triethyl amine. The monomer, MPBSK was polymerized in methyl ethyl ketone (MEK) at 70°C using benzoyl peroxide (BPO) as the initiator. The polymer was characterized by UV, IR, 1H‐NMR, and 13C‐NMR spectroscopy. The polymer was found to be soluble in several polar aprotic solvents and in chlorinated solvents but insoluble in aliphatic and aromatic hydrocarbons and in alcohols. The molecular weight data of the polymer as obtained from gel permeation chromatography suggests a higher tendency for chain termination by disproportionation than dimerization. The glass transition temperature of the polymer was determined by differential scanning calorimetry. Thermogravimetric analysis of the polymer carried out in air reveals that it possesses good thermal stability required of a negative photoresist. The photocrosslinking property of the polymer was investigated by irradiating the polymer solution with UV light in the presence and absence of triplet photosensitizers. The effect of the solvent on the rate of photocrosslinking of the polymer was also studied.  相似文献   

18.
Russian Journal of Organic Chemistry - The reaction of 5,5-disubstituted 4-methyl-3-phenyl-2,5-dihydrofuran-2-imines with phenyl isothiocyanate afforded...  相似文献   

19.
《Tetrahedron: Asymmetry》2000,11(6):1389-1395
A stereospecific ring contraction reaction, promoted by NaN3, was detected starting from a thiepane derivative obtained from d-sorbitol, an inexpensive alcohol sugar. The major polyfunctionalized thiolane derivative obtained was investigated as a potential glycosidase inhibitor.  相似文献   

20.
Russian Journal of Organic Chemistry - An efficient method has been developed for the synthesis of α,ω-di(spiro[adamantane-2,3′[1,2, 4,5,7]tetroxazocan]-7′-yl)alkanes by...  相似文献   

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