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硫酸氢钠催化合成乙酸β-萘酯 总被引:6,自引:0,他引:6
乙酸 β-萘酯可用做评价酯酶、或模拟酯酶活性的底物 [1,2 ] ,此类化合物可用乙酰氯在胺的作用下与酚反应制得 ,但用有机胺溶剂时后处理不方便 [3] .浓硫酸催化酸或酸酐与醇 (酚 )反应也可制得乙酸酯 ,但该法对设备腐蚀大 ,且反应体系为均相 ,存在催化剂和产物的分离问题 .近年来 ,人们开发了各种取代浓硫酸的催化剂 ,其中多相催化剂特别引人注目 [4 ] .本文考察了硫酸氢钠催化乙酸 β-萘酯的合成 ,发现其是有效的多相酯化催化剂 ,该法基本具备绿色化学的要求 .尚未见有文献报道 .醋酸酐、β-萘酚、Na HSO4 ·H2 O均为分析纯 .Na HSO4 … 相似文献
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在甲烷氧化细菌Methylosinus trichosporium IMV3011细胞内生物催化合成聚-β-羟基丁酸酯(PHB)的过程中,对影响聚合物分子量的各种因素进行了研究.发现碳源、培养基组分NH4+,NO3-,HPO24-,Mg2+,某些导向PHB合成的关键中间产物以及PHB的提取方法均会对PHB的分子量产生影响.同时,通过对胞内PHB合成酶系中关键作用酶的活性变化进行研究,发现β-酮硫解酶催化着控制进入PHB循环入口的关键反应,而PHB分子量的变化则主要取决于PHB合成酶和PHB降解酶的协同作用. 相似文献
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湿式催化氧化技术研究进展 总被引:2,自引:1,他引:2
现代化学工业的迅速发展促进了经济的快速发展,但与此同时进入水体的化学物质的种类和数量也急剧增加,给环境带来了很大的危害.因此,发展高浓度、有毒、有害的有机工业废水的高效处理技术,就显得日趋紧迫和十分重要,得到了人们的广泛关注. 相似文献
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K. I. Matveev E. G. Zhizhina V. F. Odyakov V. N. Parmon 《Russian Chemical Bulletin》1994,43(7):1142-1145
2-Methyl-1-naphthol is oxidized into 2-methyl-1,4-naphthoquinone (menadione) by air in the presence of vanadomolybdophosphoric heteropolyacids and their salts. The reaction proceeds in a biphasic system, and the yield of menadione is up to 85 %. The influence of the composition of the heteropolyacids on the rate and the selectivity of the reaction was studied, and the reaction mechanism was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1208–1211, July, 1994. 相似文献
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YANGKe-er TONGShan-ling YANYan KANGEn-hua XIAOFeng-shou LIQing CHANGXin FANGChi-guang 《高等学校化学研究》2005,21(3):326-333
In an alkaline 2-propanol solution with 5, 10,15,20-tetra (4-methoxyl phenyl) porphyrin iron chloride (TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-1 ,4-naphthoquinone(HNQ) with a yield of 62. 17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UVVis, IR, GC-MS, ^1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination. 相似文献
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4-甲基-3-硝基苯甲腈和2-甲基-5-硝基苯甲腈是重要的有机合成中间体[1,2],因其芳环上具有硝基和氰基两个第二类取代基,同时又有一个可参与反应的甲基而使得这两个化合物在有机合成领域有着广泛的应用前景.芳环上的甲基可以氧化为酸,也可进一步反应形成酰氯、酯等功能基;芳环上的氰基可水解成羧基,也可以与叠氮钠在Lewis酸催化下形成具有生物活性的四唑衍生物;芳环上的硝基经还原可形成氨基,如4-甲基-3-硝基苯甲腈通过化学反应可环合形成药物中间体6-氰基吲哚[2~4]. 相似文献
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R. K. Sharma S. K. Singh S. K. Sindhwani 《Monatshefte für Chemie / Chemical Monthly》1986,117(4):459-463
The chelation behaviour of complexes of La(III), Pr(III), Nd(III), Y(III), Sm(III) and Tb(III) with 3-hydroxy-2-methyl-1,4-naphthoquinone has been studied potentiometrically in 75% (v/v) aqueous dioxan medium at various ionic strengths. The method ofBjerrum andCalvin, as modified byIrving andRossotti, has been used to find values of
andpL. The stability constants and the values ofS
min
have been calculated. The order of stability constants was found to be: La<Pr<Nd<Sm<Tb.
Potentiometrische Untersuchungen des Komplexierungsverhaltens von Lanthanid-Ionen mit 3-Hydroxy-2-methyl-1,4-naphthochinon (HMNQ)
Zusammenfassung Das Komplexierungsverhalten der Komplexe von La(III), Pr(III), Nd(III), Y(III), Sm(III) und Tb(III) mit 3-Hydroxy-2-methyl-1,4-naphthochinon wurde potentiometrisch in 75% (v/v) wäßrigem Dioxan bei verschiedenen Ionenstärken untersucht. Die Methode vonBjerrum undCalvin in der Modifikation nachIrving undRossotti wurde zur Bestimmung der Werte für undpL benutzt. Es wurden die Stabilitätskonstanten und dieS min -Werte berechnet; die Stabilitätskonstanten ergaben folgende Reihung: La<Pr<Nd<Sm<Tb.相似文献
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A. A. Bogolyubov N. B. Chernysheva V. V. Nesterov M. Yu. Antipin V. V. Semenov 《Chemistry of Heterocyclic Compounds》2004,40(10):1305-1309
The dehydration of two 5,5-disubstituted 4-hydroxy-4-methyl-3-phenylaminooxazolidin-2-ones into the corresponding 4-methylene-3-phenylaminooxazolidin-2-ones has been carried out. The structure of the products was confirmed by X-ray diffraction analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1512–1517, October, 2004. 相似文献
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Introduction 2-Hydroxy-1,4-naphthoquinone (HNQ), existing in natural plants,1,2 is popularly separated and purified as dye or pigment. Recent research results show that, with the function to prevent the formation of protein coenzyme of HIV-I, HNQ can inhibit HIV virus from copying and propagating,3,4 HNQs derivatives and di-chloroallyl lawsone are also the inhibitor for RNA syn-thesis of cancer.5 It is well known that there is a rela-tionship between the side chain attached to HNQ an… 相似文献
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KF-Al2O3催化合成2-甲基-1-苄基苯并咪唑 总被引:1,自引:0,他引:1
苯并咪唑类杂环化合物具有杀菌、消炎、抗癌、抗氧化的活性,广泛用于食品的防虫和防腐,用于动、植物病毒的防治,人体疾病和肿瘤的防治[1-3],本文用KF Al2O3作催化剂,用DMF为溶剂,利用2 甲基苯并咪唑与苄基溴反应合成2 甲基 1 苄基苯并咪唑的新型方法,考察了诸因素对产率的影响,找出了最佳的反应条件。合成路线如下:1 实验部分1 1 仪器与试剂Brurer AM 500超导核磁共振波谱仪(溶剂CDCl3);CarloErbal1106型元素分析仪,NicoletIm pact410型红外光谱仪,KBr压片,HP1100型和Finnigan FTMS 2000型质谱仪(以上均由华东理工大学分析… 相似文献
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I. V. Ukrainets O. V. Gorokhova L. V. Sidorenko N. L. Bereznyakova 《Chemistry of Heterocyclic Compounds》2007,43(1):58-62
A preparative method of obtaining 1-substituted 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acids is proposed. Features
of their spatial structure have been studied.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 69–74, January, 2007. 相似文献