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以仲胺、氧杂环丁-3-酮和三甲基氰硅烷为原料,无水甲醇为溶剂,无需催化剂,一步反应合成目标化合物3-仲氨基氧杂环丁烷-3-腈衍生物(1a~1d),产物结构经1H NMR和ESI-MS表征。并以异吲哚啉、氧杂环丁-3-酮和三甲基氰硅烷的反应为模型反应,考察影响产物1a收率的主要因素,确定最佳反应条件为:物料摩尔比为n(异吲哚啉): n(氧杂环丁-3-酮): n(三甲基氰硅烷)= 2.0 : 1 : 2.5;反应溶剂为无水甲醇,在65 ℃反应6 h。在最佳反应条件下,化合物1a收率78.3 %。对于目标化合物的应用进行了研究,发现化合物1a与苯基溴化镁在四氢呋喃溶剂中,室温反应5 h,得到2-(3-苯基氧杂环丁烷-3-基)异吲哚啉(4)和 [3-(异吲哚啉-2-基) 氧杂环丁烷-3-基](苯基)甲酮(5),收率分别为40.1 %和31.5 %。 相似文献
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超声提取/高效液相色谱法测定土壤中的4-壬基酚 总被引:1,自引:0,他引:1
在考察不同提取方法和有机溶剂提取效率的基础上,建立了土壤样品中内分泌干扰物4-壬基酚(4-NP)的超声提取/高效液相色谱(紫外检测器)分析方法。结果显示,以二氯甲烷作提取溶剂时超声提取对土壤中4-NP的提取效率高于索氏提取法;不同有机溶剂的超声提取效率依次为二氯甲烷-甲醇(9∶1)>二氯甲烷>甲醇≈丙酮。样品采用二氯甲烷-甲醇(9∶1)超声提取,经硅胶柱净化、高效液相色谱检测,土壤在4-NP的高、中、低3个加标水平下的平均回收率为91%~94%,相对标准偏差为4.3%~7.2%,方法的检出限为2.0 μg/kg。采用该方法对广东省部分土壤中的4.NP进行检测,得到其含量为5.3~16 μg/kg(干重),低于河北省污水灌溉土壤中的含量。该方法简便快捷、灵敏、重现性好,适用于土壤样品中4-NP的分析。 相似文献
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《理化检验(化学分册)》2017,(4)
样品引入加速溶剂萃取池中,以丙酮-二氯甲烷(1+1)混合液为提取剂,在120℃下进行静态提取10min。提取液用装有硅胶和中性氧化铝的柱子进行净化,以正己烷-丙酮(9+1)混合液为淋洗液。洗脱液采用气相色谱法进行分离,外标法定量。各化合物的质量浓度在一定范围内呈线性,检出限(3S/N)在0.02~0.17mg·L~(-1)之间。按标准加入法在3个浓度水平上进行回收试验,回收率在72.1%~91.7%之间,测定值的相对标准偏差(n=6)在1.8%~16%之间。 相似文献
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采用加速溶剂萃取法(ASE)提取了海洋沉积物中的正构烷烃,并对ASE的萃取剂比例、萃取温度、静态萃取时间以及循环次数等实验条件进行优化。结果表明,当样品长碳链正构烷烃含量较高或需要检测长碳链正构烷烃含量时,可使用甲醇-二氯甲烷(1∶3)作为萃取剂;而甲醇-二氯甲烷(1∶9)适用于短碳链正构烷烃含量较高或需要检测短碳链正构烷烃含量的样品。加速溶剂萃取提取沉积物中正构烷烃的最佳条件为:萃取温度150℃,静态提取时间15 min,循环3次。在优化条件下,测定沉积物样品中正构烷烃的精密度除C15为20%外,其余为3%~14%,替代物回收率为84%~114%。相比于传统的索氏提取法,该方法的工作效率高、回收率高、精密度良好,适用于沉积物样品中正构烷烃的定量分析。 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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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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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献