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以2,4-二羟基二苯甲酮、4-羟基苯乙酮(HAP)为原料分别和环氧氯丙烷反应,经微波辐照合成了两种反应性紫外线吸收剂2-羟基-4-缩水甘油醚基二苯甲酮(HEPBP)和4-缩水甘油醚基苯乙酮(EPAP)。结构采用红外光谱、核磁和质谱表征。最佳合成条件为:n(羟基芳香酮)∶n(环氧氯丙烷)=1∶3,微波功率400W,于90℃反应15min,收率分别是52.6%和58.3%。与常规合成方法比较,微波合成法能降低反应温度、大大地缩短反应时间。产物中环氧丙烷基团的引入能明显改善芳香酮类紫外线吸收剂的紫外吸收性能。 相似文献
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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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通过水热法制备出以含N原子的芳香化合物、柠檬酸钠和乙二胺为原料的水溶性碳点紫外吸收剂,并对不同芳香族化合物制备的碳点进行老化试验,最终筛选出具有耐老化性能的碳点(A-CDs),其中,富含—COOH、—NH2等官能团且具有紫外全吸收性能,并进一步通过优化反应条件提高了其吸收性能。将A-CDs与聚乙烯醇(PVA)复合,形成高性能的紫外屏蔽膜。当CDs的质量分数从0.02%增加至0.1%时,紫外透过率从8%降低至3%,说明碳点能在薄膜中稳定存在。同时,碳点的加入可以降低薄膜在紫外照射下的衰老速率,维持薄膜的力学性能。 相似文献
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剪碎后的纺织品样品0.5000 g经30 mL甲醇于60℃超声提取30 min,冷却至室温后,取上清液用0.45μm有机滤膜过滤,采用高效液相色谱法同时测定滤液中11种二苯甲酮类紫外吸收剂的含量.以xBridge shield RP C18色谱柱(250 mm×4.6 mm,5μm)为分离柱,用0.1%(体积分数,下同... 相似文献
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利用聚甲基氢硅氧烷(PHMS)与4-(β-羟基-γ-烯丙氧)丙氧基-2-羟基二苯甲酮(MUV-O)、α-烯基聚醚(F6)的硅氢化加成反应,合成了一种新型聚醚-二苯甲酮衍生物侧基聚硅氧烷PE-PUVSi,用红外光谱(IR)、紫外光谱(UV)、核磁共振氢谱(1H-NMR)以及原子力显微镜(AFM)等仪器对产物的结构和成膜形态进行了研究。结果表明,新合成的PE-PUVSi对波长为243.6、289.2、325.0nm的紫外光有强吸收作用。在纤维及单晶硅表面,PE-PUVSi均可成膜。但宏观上平滑的PE-PUVSi膜,微观上实则呈非均一、相分离结构,其中UV侧基以纤细尖峰分布在聚硅氧烷膜表面,而亲水性聚醚基团则卷曲堆积成峰包。 相似文献
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本文采用电子光谱法、荧光光谱、粘度法等方法研究了4种二苯甲酮类(benzophenone,BPs)紫外吸收剂:二苯甲酮(BP)、2,4-二羟基二苯甲酮(UV-0)、2-羟基-4-辛氧基二苯甲酮(UV-531)和2-羟基-4-甲氧基二苯甲酮(UV-9)与鲱鱼精DNA(hs-DNA)的相互作用,并采用凝胶电泳考察了BPs对pBR322质粒DNA迁移作用的影响。结果表明,BPs可引起DNA在~260 nm处的特征紫外吸收峰小的红移(~2 nm)和明显的增色效应(2.1~106%);BPs可竞争亚甲基蓝(methylene blue,MB)与DNA的结合,使得DNA-MB体系中的荧光强度随着BPs的加入而增大;DNA在Tris缓冲液中的相对粘度几乎不随BPs浓度的增加而改变;BPs虽然可以使pBR322质粒DNA的超螺旋构型(Form I)比例有所下降,但对其构型和迁移速率的影响均不显著。热力学研究表明BPs与DNA的结合常数K为10~4~10~(5 )L·mol~(-1)。结合分子对接模型计算推测:BPs与DNA可能通过范德华力以沟槽式相结合。 相似文献
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Nitration of certain phenols and naphthols in the presence of biodegradable cellulose-supported Ni(NO3)2 · 6H2O/2,4,6-trichloro-1,3,5-triazine was carried out in acetonitrile at room temperature. Ortho nitrated phenols were obtained regioselectively within a short reaction time with good yields. The reaction condition was mild, and the employed cellulose could be recovered several times for further use. 相似文献
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An efficient and convenient procedure has been developed for the synthesis of benzopyran derivatives by one-pot condensation of substituted salicyaldehydes and substituted 1,3-hexanediones in the presence of a catalytic amount of 2,4,6-trichloro-1,3,5-triazine (TCT, cyanuric chloride) under solvent-free conditions. 相似文献
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Jigar Panchal Sonika Jain Pankaj Kumar Jain Dharma Kishore Jaya Dwivedi 《Journal of heterocyclic chemistry》2021,58(11):2049-2066
The greener methodology to synthesize s-triazine derivatives (also known as TCT) is described, including synthesis through microwave, ultrasound, and solvent-free conditions. This review mainly focuses on reactions of TCT (2,4,6-trichloro-1,3,5-triazine) with various substituents having amine and hydroxy functionalities to give corresponding triazine derivatives under a greener approach. The results of reactions indicate that, unlike classical methods, green methods result in better yields of the product, through a rapid reaction, under mild reaction conditions, and by easy workup procedures. 相似文献
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本文通过Suzuki偶联反应高效合成了两种三萘基三嗪化合物,即2,4,6-三(1-萘基)-1,3,5-三嗪(T1NT)和2,4,6-三(2-萘基)-1,3,5-三嗪(T2NT). 考察了介质的极性、温度以及THF-H2O二元溶剂体系中的溶解性等因素对它们吸收和发射光谱行为的影响.研究发现, 由于T1NT比T2NT具有更好的分子平面性,其激发态下分子内电荷转移的程度较大,导致其在溶液中吸收光谱、发射光谱比T2NT呈现显著红移.冻结态下,分子平面性较差的T2NT显示出较短波长的发光. 相似文献
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A new series of synthesis of 2-tert-butylimino-3-hepta-O-benzoyl-β-D-lactosylimino-4-S-benzyl-6-arylimino-2,3-dihydro-1,3,5-thiadiazines (hydrochloride) were synthesized by the interaction of 1-aryl-5-hepta-O-benzoyl-β-D-lactosyl-2-S-benzyl-2,4-isodithiobiurets with tert-butyl isocyanodichloride. The identities of these newly synthesized N-lactosides have been established on the basis of usual chemical transformations and infrared, 1H NMR, and mass spectral analysis.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
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Dimerization and formylation of p-alkyl-substituted phenols have been successfully achieved in one pot, using 2,4-dichloro-6-methoxy[1,3,5]triazine (DCMT)-activated dimethylsulfoxide. Similarly, the d5-labeled products have been prepared in high selectivity. To the best of our knowledge, the products are of new skeletons, which have not been reported to date. A plausible mechanism is proposed based on the experiments. 相似文献
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在溶剂热条件下,将2,4,6?三(2?吡啶基)?1,3,5?三嗪(2?TPT)、2,5?呋喃二羧酸(2,5?H2FCA)分别与不同类型的金属硝酸盐(Zn、Cd和Mn)进行组装,得到了3个2?TPT基配合物:[Zn(2?TPT)(2,5?FCA)](1)、[Cd(2?TPT)(2,5?FCA)]·1.5H2O(2)和[Mn(2?TPT)(2,5?FCA)](3)。通过单晶X射线衍射、粉末X射线衍射、FT?IR、UV?Vis、差热-热重、电子顺磁共振和X射线光电子能谱对1~3的结构和光致变色性能进行了表征,并详细地探究了其光致变色机理。配合物1~3表现出明显差异的光诱导分子间电子转移和光致变色性能,主要体现在光响应速率和颜色对比度2个方面。其中,1的光致变色性能明显优于2,而3不具有光致变色行为。这种明显差异的光致变色行为,主要归因于不同类型的金属及其配位模式的差异所引起的不同晶体堆积模式和电子给体-受体间相对位置关系(界面关系),体现出了金属对于光致变色性能的调控作用。 相似文献
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《Journal of heterocyclic chemistry》2017,54(2):904-910
This study introduces an efficient method for the selective formylation of indoles and pyrroles at the positions of C(3) and C(2), respectively. The mixture of three equivalents of N ,N‐dimethylformamide and one equivalent of 2,4,6‐trichloro‐1,3,5‐triazine (cyanuric chloride) generates an easy handling formylating agent for the efficient formylation of these classes of compounds to give the corresponding aldehydes under mild reaction conditions. This procedure was highly efficient, and a range of formylated indoles and pyrroles were obtained in good to excellent yields. 相似文献
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Vatsadze S. Z. Titanyuk I. D. Chernikov A. V. Zyk N. V. 《Russian Chemical Bulletin》2004,53(2):471-473
A new chemoselective procedure was developed for the synthesis of 2,4,6-triiodoaniline and 2,4-diiodoaniline by the reaction of aniline with potassium dichloroiodate in dilute HCl. Subsequent deamination of 2,4,6-triiodoaniline afforded 1,3,5-triiodobenzene in good yield. 相似文献
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A. V. Shastin T. I. Godovikova B. L. Korsunskii 《Chemistry of Heterocyclic Compounds》2003,39(8):1037-1040
Acylation of 2,4,6-tris(tert-butoxycarbonylmethyl)-1,3,5-triazine with acetic anhydride in the presence of lithium hydride with subsequent removal of the tert-butoxycarbonyl groups with trifluoroacetic acid leads to 2,4,6-tris(acetonyl)-1,3,5-triazine, the cyclic analog of -cyanoacetone. The special spectral features of this compound compared with triazines obtained previously are discussed. 相似文献