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侧链中含二苯甲酮基的聚硅氧烷的合成与结构表征 总被引:3,自引:0,他引:3
在相转移催化剂四乙基溴化铵作用下,利用2,4-二羟基二苯甲酮与烯丙基缩水甘油醚在碱性水溶液中的开环加成反应,合成了中间体4-(β-羟基-γ-烯丙氧)丙氧基-2-羟基二苯甲酮(MUV-0),将其进-步与聚甲基氢硅氧烷进行硅氢化加成反应。合成了侧链中含二苯甲酮基的聚有机硅氧烷。用元素分析、红外光谱、紫外光谱和核磁共振等仪器对中间体以及目标聚硅氧烷的结构进行了表征和测定。结果表明:中间体和聚硅氧烷在紫外光区均具有二苯甲酮衍生物特有的三条吸收谱带,对波长240~400nm的紫外光有良好的吸收作用。 相似文献
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紫外接枝聚合聚乙二醇甲基丙烯酸甲酯制备抗污染聚砜超滤膜 总被引:1,自引:0,他引:1
以二苯甲酮(BP)为紫外引发剂,将聚乙二醇甲基丙烯酸甲酯(PEGMA)接枝在聚砜超滤膜表面以提高膜的抗污染性能.在二苯甲酮存在的条件下,波长较长(λ300nm)的紫外光(UV)辐射下发生提氢反应,可以有效防止聚砜分子主链的剪切,保持改性膜的分离性能.考察了PEGMA浓度、UV辐射时间和BP浓度对改性超滤膜接枝度、亲水性和抗污染性能的影响.用表面全反射红外光谱(ATR/FTIR)表征改性前后膜表面化学组成的变化.表面改性膜的纯水通量略有降低而牛血清白蛋白(BSA)截留率有所提高.随着接枝度的提高,PEGMA接枝改性膜的抗污染性能增加. 相似文献
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4-甲基二苯甲酮经N-溴代丁二酰亚胺溴代制得4-溴甲基二苯甲酮(1);1与3,5-二羟基苯甲醇反应合成了外围带有二苯甲酮取代基的第一代树枝状分子3,5-二(二苯甲酮-4-甲氧基)苯甲醇(2);2与4-硝基邻苯二甲腈缩合制得外围带有二苯甲酮取代基的第一代树枝状分子4-[3,5-二(二苯甲酮-4-甲氧基)苯甲氧基]邻苯二甲腈(3);3经"液相法"环合生成外围带有二苯甲酮取代基的第一代树枝状分子取代的酞菁锌配合物——四[3,5-二(二苯甲酮-4-甲氧基)苯甲氧基]锌酞菁[ZnPc(C35H27O5)4],其结构经UV,1HNMR,IR和MS表征。 相似文献
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以含氢聚硅氧烷(PMHS)分别与甲基丙烯酸六氟丁酯(HFMA)和烯丙基缩水甘油醚(AGE),经氯铂酸催化硅氢加成反应将甲基丙烯酸六氟丁酯和烯丙基缩水甘油醚引入聚硅氧烷的侧链,合成了3种含氟量不同的含氟代烃侧基/环氧侧基聚硅氧烷(EFPS),用FTIR、1H-NMR和13C-NMR进行了结构表征,将这类聚硅氧烷与环氧树脂... 相似文献
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以4-(3-苯基-4-羟基苯基)-2,3-二氮杂萘-1-酮(DHPZ-P)、 4-(4-羟基苯基)-2,3-二氮杂萘-1-酮(DHPZ)和1,4-二(4'-氟苯甲酰基)苯(BFBB)为原料, 经溶液亲核取代缩聚反应, 通过调节DHPZ-P和DHPZ的比例, 合成了一系列侧苯基杂萘联苯聚醚酮酮(PPEKK-P), 然后以浓硫酸为磺化剂, 制备出一系列磺化侧苯基杂萘联苯聚醚酮酮(SPPEKK-P). 利用傅里叶变换红外光谱(FTIR)和氢核磁共振谱(1H NMR)对聚合物结构进行表征, 结果表明, 磺酸基团引入到聚合物链的侧苯基上. 采用溶液浇铸法制备SPPEKK-P质子交换膜. SPPEKK-P膜的吸水率、 溶胀率和质子传导率均随离子交换容量(IEC)的增加而增加, 且具有较好的耐氧化性. IEC最高的SPPEKK-P-100膜的质子传导率在95℃能达到7.44×10-2 S/cm, 且甲醇渗透系数为5.57×10-8 cm2/s, 阻醇性能优于Nafion117膜. 相似文献
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合成了侧链带有咔唑的N-丙烯酰氧己基咔唑(MACZ),通过自由基聚合得到聚N-丙烯酰氧己基咔唑(PMACZ),在四氢呋喃含10%三氟化硼乙醚与四氟化硼四丁基胺的混合电解质溶液中,直接阳极氧化PMACZ获得自支撑交联网状的聚(聚N-丙烯酰氧己基咔唑)(PPMACZ)薄膜.PPMACZ薄膜具有良好的氧化还原性和热稳定性,电导率为1.34×10-5S·cm-1.1HNMR和红外光谱表明PMACZ二次聚合反应发生在咔唑单元的3,6位上,荧光光谱表明PPMACZ薄膜是一种良好的蓝色发光材料. 相似文献
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An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction. 相似文献
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The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed. 相似文献
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Xi-Liu YunWen-Ying Bi Jian-Hui HuangYu Liu Daisy Zhang-NegrerieYun-Fei Du Kang Zhao 《Tetrahedron letters》2012,53(38):5076-5080
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring. 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles. 相似文献