共查询到20条相似文献,搜索用时 46 毫秒
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以高效、廉价易得的Pd2dba3作为催化剂,成功实现了碘代芳烃的双羰化反应,得到的α-酮酰胺最高分离收率达90%.该催化体系对于不同取代基的碘代芳烃和仲胺都具有广泛的底物适应性. 相似文献
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离子液体作为一种绿色溶剂,因其具有独特的性质和功能可以稳定产生的纳米钯颗粒.用离子液体制备了纳米钯催化剂,并成功地应用于碘代芳烃的双羰化反应,从而合成了一系列的α-酮酰胺,最高收率可达83%,丰富了α-酮酰胺的合成方法.该催化体系应用于碘代芳烃双羰化反应具有广泛的底物适应性. 相似文献
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芳香型螺双内酯二胺的合成 总被引:2,自引:0,他引:2
以对硝基甲苯和多聚甲醛为原料,经过两种途径合成了二氨基芳香型螺双内酯--6,6′-二氨基-3,3′-螺双苯酞.发现二(2-甲基-5-硝基苯基)甲烷在酸性体系中经氧化反应可高收率地得到二硝基螺双内酯,还原二硝基螺双内酯时发现,在低极性溶剂中主要生成一种稳定的芳香型羟胺类化合物--6,6′-二羟氨基-3,3′-螺双苯酞,在高极性溶剂中主要生成6,6′-二氨基-3,3′-螺双苯酞.通过1HNMR,13CNMR,IR,MS及元素分析确证了二氨基螺双内酯及其中间产物的结构 相似文献
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一类新型的双β-氨基醇的合成及催化硼烷对芳酮的不对称还原反应 总被引:7,自引:0,他引:7
以L-半胱氨酸盐酸盐出发,经与二卤代烷偶联,成酯和格氏反应制得三种双手性β-氨基醇,1,2-双[R-2-氨基-3-羟基-3,3-二苯基丙硫基]乙烷(4a),1,3-双[R-2-氨基-3-羟基-3,3-二苯基丙硫基]丙烷(4b),1,4-双[R-2-氨基-3-羟基-3,3-二苯基丙硫基]丁烷(4c)。将此类双手性β-氨基醇与硼烷在THF溶液中反应,in situ制备双手性恶唑硼烷催化硼烷对芳酮的不对称还原,产物苯乙醇的光学收率达72.8%、α-溴代苯乙醇的光学收率达91.4%。 相似文献
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双邻位甲基取代的聚芳醚酮合成与表征 总被引:3,自引:0,他引:3
两种单体 2 ,2′ ,6 ,6′ 四甲基 4 ,4′ 二苯氧基二苯酮 (o M2 DPOBP)和 2 ,2′ ,6 ,6′ 四甲基 4 ,4′ 二苯氧基三苯二酮 (o M2 DPOTPDK) ,分别与对苯二甲酰氯 (TPC)和间苯二甲酰氯 (IPC)低温亲电溶液缩聚 ,合成了 4种含双邻位甲基侧基聚醚酮醚酮酮 (DM PEKEKK和DM PEKEKMK)及含双邻位甲基侧基聚醚酮酮醚酮酮 (DM PEKKEKK和DM PEKKEKMK)聚合物 .用FT IR、1 H NMR、DSC、TGA、WAXD等方法对聚合物进行了表征 ,研究了聚合物的溶解性能 .结果表明 ,该 4种聚合物具有较高的玻璃化转变温度 ,良好的热稳定性和优良的溶解性能 . 相似文献
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微波促进活性炭负载磷钨酸催化合成短链季戊四醇双缩醛 总被引:2,自引:0,他引:2
以活性炭负载磷钨酸为催化剂,用微波辐射法合成了5种短链季戊四醇双缩醛(3a~3 e),其中季戊四醇双缩丙醛(3b)未见文献报道。3的结构经1H NMR,IR和元素分析表征。 相似文献
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This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid acid catalyst under thermal solvent‐free conditions. 相似文献
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JIN Tong-Shou YANG Mi-Na FENG Guo-Liang LI Tong-Shuang 《有机化学》2003,23(Z1):94-94
Pentaerythritol diacetals are useful in many fields. They can be applied as plasticizers and vulcanizers of various polymeric materials, as raw materials for production of valuable resins and lacquers, as physiologically active substances and as defoamers for washing solution containing anionic surfactants. [ 1 ~ 4] Synthsis of diacetals from 2,2bis(hydroxymethyl)-1, 3-propanediol with aldehydes and ketones in refluxing toluene using ZrO2/S2O2- 8 solid superacid as catalyst in 85% ~ 99% yields has been described. The catalysts are easily regenerated by washing with ethanol followed by drying at 120 ℃ for 4 h and could be reused 5 times for the synthesis pentaerythritol diacetal 3e without significant loss of activity. This method possesses the advantages of the operational simplicity, short reaction time, use of inexpensive materials, non-corrosion, non-polluting, high yields and reusable catalysts. 相似文献
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<正>In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SO_3H-functionalized ionic liquids(ILs) as catalysts was reported.The ILs show high catalytic activity and reusability with good to excellent yields of the desired products.Hammett method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization reaction.Maximum product yield of 93%was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss. 相似文献
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Chandrashekar Ramarao Ramadevi Nandipati Rajasekhar Navakoti Ramanjaneyulu Kottamasu 《Tetrahedron letters》2012,53(6):637-640
1,2-Dihydroxy benzenes have been protected as cyclic diacetals using 2,3-butane dione. These diacetals are extremely robust and can be further chemically diversified and resolved with chirality embedded in the 1,4-dioxane ring attached to the aromatic back bone as a result of the anomeric effect. These systems can serve as ligands, auxiliaries or organocatalysts for asymmetric synthesis. 相似文献
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Summary The hydrogenation of the diacetals of furan dialdehydes gave the previously unknown diacetals of tetrahydrofuran dialdehydes, which by hydrolysis were converted to the previously unknown dialdehydes of the tetrahydrofuran series.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 380–381, February, 1965 相似文献
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A number of cyclic diacetals of but-2-ynedial, fumaraldehyde, andα, α'-dibromosuccinaldehyde have been synthesized by the transacetalation of bis(dimethyl acetal)s of 1,2- and 1,3-glycols. The succinaldehyde derivatives have also been obtained by the bromination of the corresponding diacetals of fumaraldehyde. 相似文献