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Pd(OAc)2/HQ/FePc催化环己烯氧化合成环己酮反应机理 总被引:4,自引:0,他引:4
在醋酸钯[Pd(OAc)2]/氢醌(HQ)/酞菁铁(FePc)催化环己烯氧化合成环己酮反应中,应用XPS、UV-Vis,IR和循环伏安法考察了经剂各组分在反应前后存在状态,以及Pd(OAc)2,Pd(OAc)2/BQ(苯醌)对环己烯的作用,FePc对HQ的催化氧化,讨论了Pd(OAc)2/HQ/FePc催化环己烯氧化合成环己酮的作用机理。 相似文献
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钯催化环己烯氧化合成环己酮 总被引:7,自引:0,他引:7
考察了由不同金属酞菁(MPc,M=Fe,Co,Cu)氯代金属卟啉(MTPPC.,M=Fe,Cr,Mn)和Pd(OAc)2(醋酸钯)/HQ(氢醌)组成的催化体系对环己烯氧化成环己酮的催化活性。表明,在乙腈酸性水溶液中,Pd(OAc)2/HQ/FePc催化体系对环己烯氧化合成环己酮显示出较高的催化活性,在30min内环己酮收率可达84%,选择性>98%,研究了各种因素对体系催化活性的影响。 相似文献
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Pd(OAc)_2/HQ/FePc、Pd(OAc)_2/FePc 催化烯烃氧化合成酮的研究 总被引:2,自引:0,他引:2
考察了在乙腈酸性水溶液中Pd(OAc)2/氢醌(HQ)/酞青铁(FePc)和Pd(OAc)2/FePc对环己烯、环戊烯、苯乙烯、正癸烯氧化合成相应酮的催化活性.实验结果表明,两类催化体系对环戊烯的酮基化均呈现出较高的催化活性,环戊酮收率可达98%.在其它烯烃的氧化反应中,三元催化体系Pd(OAc)2/HQ/FePc的催化活性高于二元的Pd(OAc)2/FePc.这表明,在Wacker类催化体系中,电子传递体的作用是很重要的.对催化体系中各组分的作用进行了讨论,并给出了可能的催化作用机理. 相似文献
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高效液相色谱法快速测定食品中抗氧化剂BHA,BHT 总被引:9,自引:0,他引:9
采用甲醇浸提食品样品中抗氧化剂BHA(叔丁基羟基茴香醚)和BHT(二叔丁基羟基甲苯),然后用高效液相色谱法测定提取液中的BHA和BHT。该法简单快速,准确性好,BHA和BHT的最小检出量分别为5ng和10ng。 相似文献
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氢醌单丙酸酯的改进合成 总被引:2,自引:0,他引:2
氢醌单丙酸酯的改进合成马美玲(西安地质学院应用化学系,西安710054)邓月松谢明贵(四川大学化学系,成都610064)关键词除色素剂氢醌单羧酸酯氢醌单丙酸酯中图分类号O625.323氢醌单脂肪酸酯是一类很好的皮肤去色素剂,其中尤以氢醌单丙酸酯为最佳... 相似文献
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Three synthetic phenolic antioxidants, tertiary butyl hydroquinone, butylated hydroxytoluene, and butylated hydroxyanisole, were determined in vegetable oil and oil-enriched food by high-performance liquid chromatography (HPLC) with electrochemical detection. The separation was achieved using a reverse-phase column and gradient elution with methanol and 1% acetic acid. The limits of detection and quantification of the analytes were 2–120 lower, higher than those obtained by diode-array detection. The recoveries were 103.3% for tertiary butyl hydroquinone, 97.3% for butylated hydroxyanisole, and 95.2% for butylated hydroxytoluene. The results showed that HPLC with electrochemical detection is suitable for the quantification of low concentrations of phenolic antioxidants in vegetable oil and oil-enriched food with high sensitivity and accuracy. 相似文献
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生物柴油的氧化安定性是确保生物柴油品质的关键因素。本文采用欧盟标准(EN14214-2002),使用瑞士万通公司生产的873型生物柴油氧化安定性测定仪,采用在植物油抗氧化方面最常用、最有效的特丁基对苯二酚(TBHQ)对由地沟油、大豆油和棉籽油制成的生物柴油的抗氧化性进行了系统的定量研究。结果表明,当添加量大于0.6‰时,3种生物柴油抗氧化时间均超过国标规定的6h。TBHQ是一种理想的生物柴油抗氧化剂,对比另一种常用的抗氧化剂BHA(叔丁基对羟基茴香醚)抗氧化性能优势明显。 相似文献
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Various organoselenium compounds (diselenides, benzisoselenazol‐3(2H)‐ones, and 1,3,2‐thiaselenazolones) are effective catalysts for oxidative dealkylation of hydroquinone ethers with t‐butyl hydroperoxide to 1,4‐quinones. The reactions is most efficient when t‐butyl hydroperoxide in the presence of poly(bis‐1,2‐phenyl) diselenide is used as an oxidizing agent. In this way 1,4‐benzo and 1,4‐naphthoquinones are produced in good to high yields. 相似文献
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实验室中合成叔硫醇缺少简便方法。用叔醇和氢溴酸与硫脲直接反应是目前采用的方法。Lee和Akerstrom曾用此法合成了叔硫醇,但碳原子数没超过七个。Sprague及Kresze分别用干燥氯化氢及盐酸代替氢溴酸也合成了叔硫醇,但产率不高。本文提出了用叔醇、硫酸与硫脲反应来制备叔硫醇的方法,并合成了六个叔硫醇。 相似文献
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A. B. Remizov D. I. Kamalova R. A. Skochilov I. A. Suvorova N. N. Batyrshin Kh. E. Kharlampidi 《Journal of Molecular Structure》2004,700(1-3):73-79
Self-association of cumyl, tertiary butyl and 3-phenylmethyl hydroperoxides in solutions of n-decane, carbon tetrachloride and chlorobenzene were studied by IR spectroscopy (3100–3700 cm−1, 293–353 K). The experimental data were interpreted by factor analysis and band contour resolution. The di- and trimerization constants and thermodynamic parameters of self-associates were determined. Intramolecular hydrogen bond of cumyl hydroperoxide was investigated. The conformations of tertiary butyl and cumyl hydroperoxides were studied. The solvent influence on the thermodynamic parameters of hydrogen bond was found. 相似文献
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David J. Zillman 《Tetrahedron letters》2010,51(23):3033-3036
Mixed organoboranes based on diphenyl- or dimethylalkylboranes transfer the alkyl group in the reductive alkylation of p-benzoquinone to form the alkylhydroquinones in very high yields. The auxiliary groups do not transfer or have a low migratory aptitude. Primary and secondary alkyl groups are transferred with retention of regio- and stereochemistry to the hydroquinone. O-Alkylation is the major product with tertiary and secondary groups with steric bulk in proximity to the site of attachment. The presence of metal salts, such as magnesium, results in reduction to the unsubstituted hydroquinone. This reaction makes the first practical route to alkylhydroquinones via organoboranes. 相似文献
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Gorkem Sahin Aylin Ziylan Albayrak Zeynep Sarayli Duygu Avci 《Journal of polymer science. Part A, Polymer chemistry》2006,44(23):6775-6781
Novel aromatic mono‐ and diphosphonate monomers based on t‐butyl α‐bromomethacrylate were prepared for use in dental composites. The synthesis of the two monomers involved three steps: the reaction of diethyl phosphite with phenol or hydroquinone, the rearrangement of the resulting phosphate derivatives into o‐hydroxyaryl phosphonates with lithium diisopropylamide, and the reaction of o‐hydroxyaryl phosphonates with t‐butyl α‐bromomethacrylate. Then, the selective hydrolysis of the t‐butyl ester groups of the monomers with trifluoroacetic acid gave the other carboxylic acid containing monomers. The photopolymerization behaviors of the synthesized monomers with glycerol dimethacrylate and triethylene glycol dimethacrylate were investigated with photodifferential scanning calorimetry at 40 °C with 2,2′‐dimethoxy‐2‐phenyl acetophenone as the photoinitiator. The hydrolysis of the t‐butyl groups of the monomers increased the reactivity and the rates of polymerization of the monomers. The mixtures of the acid monomers showed rates of polymerizations similar to those of homopolymerizations of triethylene glycol dimethacrylate and glycerol dimethacrylate. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6775–6781, 2006 相似文献
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L. I. Vereshchagin R. I. Katkevich S. P. Korshunov 《Chemistry of Heterocyclic Compounds》1967,3(6):774-775
The aminomethylation of primary, secondary, and tertiary alcohols of the furan series and also of butyl pyromucate under the conditions of the Mannich reaction has given the corresponding aminomethylsubstituted compounds. 相似文献
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Homogeneous polymerization of butyl methacrylate (BMA) using Pd(II)‐ and Ni(II)‐based acetylide complexes as single‐component initiators has been investigated in CHCl3 at 60°C. M(PPh3)2(C = CR)2 (M = Pd, Ni; R = Ph, CH2OH, CH2OOCCH3) were found to be a novel type of effective initiators for the polymerization of butyl methacrylate. Among them, Pd(PPh3)2(C‐CPh)2 (PPP) shows the highest activity. Besides, PPP alone can also initiate the homogeneous polymerizations of acrylates, e. g., methyl acrylate (MA), and n‐butyl acrylate (BA). The present type of polymerization is not hindered by the incorporation of hydroquinone. 相似文献