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1.
蒽酮1和氯甲基吡啶盐酸盐2在甲苯中回流反应生成10,10-二吡啶甲基-9(10H)蒽酮(3),收率63%~68%;3用硼氢化钠还原生成10,10-二吡啶甲基-9,l0-二氢蒽-9-醇(4),收率87%~90%;蒽醇4在酸催化下发生歧化反应,得到还原产物10,10-二吡啶甲基-9,10-二氢蒽(5)和氧化产物蒽酮3.该歧化反应受催化剂、溶剂和反应温度等影响.当蒽醇4用三氟化硼为催化剂、甲苯为溶剂、回流反应,5的收率达到74%.所合成的新化合物都经1H NMR,13C NMR,MS和元素分析表征确认.  相似文献   

2.
用超临界二氧化碳重结晶分离菲蒽混合物   总被引:3,自引:0,他引:3  
方瑞斌 《分析化学》1997,25(9):1001-1005
建立了一套以超临界二氧化碳及其改性流体为重结晶溶剂的等压温差超临界流 重结晶实验装置。用色谱保留值法评价了SFR分离菲蒽的试验条件。研究了该实验装置影响重结晶的因素,并对同分异构体型菲蒽模型混合物进行了SFR分离纯化。  相似文献   

3.
分枝定界法用于多组分同时定性定量分析,只需解析一份试样测得的数据,即可同时得到待测样品中所含组分的种类、数目及含量,具有简单、快速、准确等优点。此文对分枝定界法在判据应用方面进行了改进,应用四个判据,解决了最佳子集难判断的问题。建立了精蒽中不经分离同时测定蒽、菲和咔唑的方法。  相似文献   

4.
蒽酮与β-硝基苯乙烯的不对称Michael加成反应   总被引:1,自引:0,他引:1  
不对称催化Michael加成反应是一类重要的形成碳—碳键的反应,以蒽酮作为亲核试剂的不对称Michael反应报道甚少.以手性伯胺硫脲作为催化剂,对蒽酮与硝基苯乙烯的不对称有机催化Michael加成反应进行了研究.实验结果表明,所用的伯胺硫脲均具有较好的催化活性(80%~95%收率),其中硫脲4a得到了较高的对映选择性.对反应条件进行优化后,以乙醚为溶剂,使用5%摩尔分数催化剂4a和苯甲酸,研究了多个硝基苯乙烯类底物和蒽酮的Michael加成反应,获得了优异的化学收率(95%~98%)和较好的对映选择性(最高86%ee).  相似文献   

5.
有机碲氧化物催化合成10-亚苄基蒽酮   总被引:1,自引:0,他引:1  
在DMSO中以双对甲氧基苯基氧化碲为催化剂缩合芳醛与蒽酮,合成了16个10-亚苄基蒽酮,产率52%-81%。  相似文献   

6.
用消解乳化技术处理丁苯橡胶样品,先用浓硝酸消解样品,再用乙醇-甲基异丁基酮混合溶剂溶解消解产物,并用乳化剂Triton X-100乳化成乳浊液。以钡离子作为钠和钾的消电离剂,以空白溶液为参比,用工作曲线法测定,建立了快速测定丁苯橡胶中钠和钾的FAES法。对溶剂及乳化剂、试液与空白溶液粘度的一致性、干扰及检出限进行了考察。测定结果的相对标准偏差小于2.4%,加标回收率98.0%~104.7%。  相似文献   

7.
采用高效液相色谱-荧光检测法测定多环芳烃化合物蒽和荧蒽。在Shim-pack CLC-plenyl柱上,以50%的乙腈水溶液作流动相,12min内实现了两组分的同时分离测定。线性范围为0-80μg/mL,检测限低于50ng/mL,相对标准偏差小于1%。  相似文献   

8.
本研究依据乳化液膜分离技术的原理,采用阴离子表面活性形成的乳化液膜从萘油直接制取精萘,考察了各种工艺条件对精萘产品质量和收率的影响。实验结果表明,以阴离子表面活性剂形成的乳化液膜结合精馏可有效地将萘油制成精萘,萘含量大于99%,符合国家精萘标准,萘收率大于88%。  相似文献   

9.
研究了对-N,N-二甲氨苯乙烯和蒽乙烯生成的激基缔合物在不同极性溶剂中的荧光特性,发现其荧光发射波长随溶剂的极性增大向长波方向移动,且发现激基缔合物荧光量子产率的大小决定对-N,N-二甲氨苯乙烯和蒽乙烯的光环加成产物的产率,其中反式产物的相对产率随溶液极性增大而降低,并进一步探讨了此光环加成反应的机理。  相似文献   

10.
研究了对-N,N-二甲氨苯乙烯和蒽乙烯生成的激基缔合物在不同极性溶剂中的荧光特性,发现其荧光发射波长随溶剂的极性增大向长波方向移动,且发现激基缔合物荧光量子产率的大小决定对-N,N-二甲氨苯乙烯和蒽乙烯的光环加成产物的产率。其中反式产物的相对产率随溶液极性增大而降低,并进一步探讨了此光环加成反应的机理。  相似文献   

11.
Abstract— The influence of a surrounding transparent matrix on the photochemical behavior of an absorbing solute has been investigated on the particular case of anthracene in KBr , KCl and in HBO2 and B2O3 glasses. In KBr compressed powders, dianthracene formation occurs with a high yield, whereas it is forbidden or negligible for pure crystalline anthracene.
Experiments show that the anthracene molecules are associated in microcrystals and suggest that the dimerization reaction occurs at the interface between KBr and anthracene crystals.
Such an influence of the heterogeneity of the irradiated medium may have implications in photobiology where heterogeneous structures are the general rule.  相似文献   

12.
Abstract— Dianthracene is efficiently photodissociated, forming anthracene with a quantum yield of about 0.63. Like anthracene, tetracene undergoes a reversible photochemical reaction, the product of which appears to be di-tetracene. In dilute, deoxygenated solutions the of quantum yeild for the formation of di-tetracene is directly proportional to the concentration of the monomer ødim = 2.2 (). The quantum yield for the reverse reaction is approximately 0.74
When dilute deaerated solutions of anthracene are irradiated with the unfiltered radiation from a quartz-mercury arc, a degradation product is formed. Unlike the dimer, this product cannot be converted into anthracene either by heating it to 200C or by irradiating it in solution with light of 254 nm. This degradation product appears to be the compound or compounds which Birks et al. believed to be dianthracene. Irradiation of deaerated solutions of anthracene (or tetracene) with light of wavelenghts longer than 300 nm produces only the dimer, which has an absorption spectrum similar to that reported by Coulson et al.  相似文献   

13.
Acylation of anthracene and oxalyl chloride in the presence of anhydrous AlCl3 was investigated. Pure 1,2-aceanthrylenedione, which is used as new functional macromolecule, was prepared by extraction and recrystallation. The structure of 1,2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1↑HNMR analyses. The influences of various parameters, such as solvent, dosage of catalyst, molar ratio of anthracene to oxalyl chloride, reaction temperature, and reaction time were studied. The anhydrous AlCl3 was found to catalyze the reaction with high yeild and good selectivity. When the reaction temperature is 303K, reaction time is 5h and molar ratio of anthracene to oxalyl chloride is 1:2, the yield and selectivity of 1,2-aceanthrylenedione is 83.8 % and 92.3% respectively.  相似文献   

14.
A microwave-assisted extraction technique was developed to optimize the extraction of phenolic compounds from grape seeds. The microwave power (300-150W) and time of extraction (20-200s) were varied during the optimization process. The polyphenol content of the resulting extracts were measured as mg of tannic acid equivalent per gram of crude extract (mg TAE/g of crude extract), using a Folin-Ciocalteau reagent. In general, neither the time nor the power had a significant effect on the overall % yield (average of 13.5%) and on the polyphenol content (392 mg TAE/g of crude extract) of the extracts. However, when the solvent polarity was changed by the addition of 10% water, the yield increased to 15.2% and the polyphenol content increased to 429 mg TAE/g of crude extract.  相似文献   

15.
测定了9-乙烯基蒽和对-N,N-二甲氨基苯乙烯体系在不同极性的溶剂中的荧光光谱和荧光量子产率。发现随着溶剂极性的增加,激基络合物的荧光发生红移,荧光量子产率降低。同时9-乙烯基蒽和对-N,N-二甲氨基苯乙烯之间的光二聚产物的相对产率也降低。并讨论了经过激基络合物中间体的光二聚反应机理。  相似文献   

16.
脱晶蒽油改质煤焦油沥青的研究——中间相非等温动力学   总被引:1,自引:0,他引:1  
在热转化装置上,对宝钢Ⅰ期焦油沥青(简称I-CTP)及其添加18%、30%脱晶蒽油(简称DCAO)制成的软沥青进行了中间相转化非等温动力学研究,采用积分法求得了有关动力学参数。结果表明,沥青中间相形成过程可以用一级反应来描述。宝钢Ⅰ期焦油沥青活化能为180.02kJ/mol。添加80%脱晶蒽油则提高了原料沥青的反应性,活化能为147.89kJ/mol,不利于优质中间相的形成。  相似文献   

17.
Photodimerization of anthracene and its derivatives has been extensively investigated[1].In general,irradiation of 9-substituted anthracene in organic solvents results in the dimerization of the aromatic rings at 9,10-positions to yield head-to-tail (h-t) rather than head(h-h)photodimers[2].  相似文献   

18.
Abstract— The interpretation of the viscosity dependence of anthracene triplet decay is shown to be complexed by the effects of the macroscopic and the microscopic viscosity of the system on the translational diffusion coefficient. The second order rate constant for the decay of the anthracene triplet as measured by flash photolysis is equal to 2.45plusmn;.30×1091. mole-1sec-1 for nearly a one hundredfold change in the viscosity of cyclohexane-polyisobutylene solutions. The translational diffusion coefficient is unaffected by the presence of the polymer, and the local viscosity of the polymer solutions is identical to that of the pure solvent.  相似文献   

19.
本文设计合成了两个典型的共轭的电子给体与电子受体(D-A)化合物:2-三氰基乙烯基蒽(2-TCVA)与9-三氰基乙烯基蒽(9-TCVA),通过极性效应,温度效应对它们基态与激发态的光谱行为进行了表征。研究表明:这两个化合物均表现出显著的电荷转移(CT)吸收峰,分子受光激发后,9-TCVA只能在非极性溶剂中产生分子内电荷转移(ICT)态荧光,而2-TCVA在极性与非极性溶剂中都能从ICT态发光。另外,温度效应显示冻结态下,2-TCVA只发射ICT态荧光,而9-TCVA既发射类蒽(anthracene-like)荧光又发射ICT态荧光,造成这一现象的主要原因可能是2-TCVA与9-TCVA分子平面性上的差异而引起分子内电荷转移相互作用不同所致。文中还利用了Bilot-Kawski公式估算了化合物2-TCVA在激发态与基态时偶极矩的差值为18.8D。  相似文献   

20.
研究了乳化剂的HLB值、乳化剂浓度、乳化温度、搅拌强度对环氧树脂E-44相反转乳化中临界含水量Rf值与乳状液稳定性的影响,探讨了环氧树脂E-44相反转机理。实验结果表明环氧树脂E-44从W/O向O/W相反转的发生与乳化剂的HLB值与浓度、乳化温度、搅拌强度等因素都有关,其Rf值随着乳化条件的不同是动态变化的。  相似文献   

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