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研究使用催化量的3-氧杂多氟戊磺酸催化等摩尔的羧酸和醇的酯化反应和催化 量3-氧杂多氟戊磺酸铜催化芳烃的Friedel-Crafts酰基化反应,并取得较好结果. 相似文献
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以固体酸为催化剂,4,4’-二氟二苯甲酮与苯胺脱水缩合,合成了N-(双(4-氟苯基)亚甲基)苯胺.比较了不同固体酸催化剂H型ZSM-5、Na型ZSM-5、介孔分子筛MCM-41(Al)及强酸型离子交换树脂Amberlyst 15的催化效果.使用比表面、NH3-TPD对催化剂进行了表征,并与催化效果关联.考察了催化剂用量、原料摩尔比、浓度及溶剂等反应条件对产物收率的影响.产物通过熔点、核磁共振谱进行了表征.结果表明,HZSM-5固体酸催化剂具有优异的催化作用.在优化条件下,以对二甲苯为反应溶剂和脱水剂,4,4’-二氟二苯甲酮0.1 mol,苯胺0.2 mol,催化剂用量2.0 g,反应24 h,产物收率达91%.此外,催化剂易于分离,能够重复使用多次. 相似文献
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合成了二氧化硅负载的聚-γ-氨两基硅氧烷(简称:SiO_2>Si-NH_2)的单金属及双金属络合物(分别简称:SiO_2>Si-NH_2-M,M=C_O或 Cu;SiO>Si-NH_2-Cu-M′,M′=Co,Sn,Mn,Ni或Fe),考察了这些高分子金属络合物对苯胺氧化乙氧羰基化生成苯基氯甲酸乙酯反应的催化作用。结果表明,铜一钻双金属络合物(SiO_2>Si-NH_2-Cu-Co)的催化活性和选择性高于其他几种金属络合物,在温和的反应条件下可使苯胺以90%以上的转化率和大于80%的选择性转化成苯基氨甲酸乙酯。考察了各种反应条件对SiO_2>Si-NH_2-Cu-Co催化性能的影响,用测定转化数的方法研究了其稳定性。 SiO_2>Si-NH_2-Cu,SiO_2>Si-NH_2-Co和SiO_2>Si-NH_2-Cu-Co的XPS及IR研究结果表明,在高分子金属络合物中,氮与金属之间形成了配位键,每种金属都存在一种以上的结构形态。双金属络合物中两种金属存在相互作用。 相似文献
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乙二胺基和2,4-戊二酮官能化介孔分子筛固载钼(Ⅵ):新型的环己烯环氧化催化剂 总被引:4,自引:0,他引:4
通过对介孔分子筛HMS和MCM-41表面修饰,将乙二胺基和2,4-戊二酮引入到介 孔分子筛孔道内,制备出乙二胺基和戊二酮官能化介孔分子筛。首次将烯烃环氧化 均相催化剂MoO_2(acac)_2固载到乙二胺基和戊二酮官能化介孔分子筛孔道内,制 备出新型的、易回收、可重复使用的烯烃环氧化多相催化剂。环已烯催化环氧化表 明,该催化剂的催化活性与均相催化剂MoO_2(acac)_2相当,选择性大于80%。 相似文献
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四(三苯基膦)钯(O)在温和的条件下能催化氟烷基碘R~FI[R~F=(CF~2)~nCl,n=2;n=4;n=6;R~F=(CF~3)~nCF~3;n=3;n=1;R~F=H(CF~2)~4]对炔烃(CH≡CC~4H~9,CH≡CSiMe~3,CH≡CPh)加成生成较高产率的加成产物.二(三苯基膦)二氯化肥(II)和二(三苯基膦)氟烷基碘化钯(II)在同样的条件下无催化作用.2,2-硝基,亚硝基丙烷能部分阻止反应,这表明反应的可能中间体是自由基,而不是二(三苯基膦)氟烷基碘化钯(II). 相似文献
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邻溴苄基溴或对溴苄基溴与锡反应合成三(邻溴苄基)溴化锡(1)和四(对溴苄基)锡(2).经X射线方法测定了新化合物的晶体结构.晶体结构1属斜方六面体晶系,空间群为R-3,晶体学参数:a=1.3389(3) nm, b=1.3389(3) nm, c=2.1896(8) nm, V=3.3993(16) nm3, Z=6, Dx=2.077 Mg·m-3, μ(Mo Kα)=81.83 cm-1, F(000)=2004, R1=0.0477, wR2=0.1372;晶体结构2属正交晶系,空间群为Fdd2,晶体学参数:a=2.1027(7) nm, b=2.3034(8) nm, c=1.1431(4) nm, V=5. 536(3) nm3, Z=8, Dx=1.917 Mg·m-3, μ(Mo Kα)=67.11 cm-1, F(000)=3056, R1=0.0358, wR2=0.0659.化合物1中Sn-C键长为0.2160(8) nm, Sn-Br键长为0.2491(3) nm;化合物2中Sn-C键长分别为0.2175和0.2178 nm.中心锡与亚甲基碳(或溴)原子构成畸型四面体. 相似文献
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研究使用催化量的 3 氧杂多氟戊磺酸催化等摩尔的羧酸和醇的酯化反应和催化量 3 氧杂多氟戊磺酸铜催化芳烃的Friedel Crafts酰基化反应 ,并取得较好结果 . 相似文献
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Esterification of carboxylic acid with equimolar amount alcohol can be efficiently catalyzed by biphasic 4-(benzylamino) formoyldiphenylammonium triflate (BDPAT,3) in good yield. The catalyst can be easily recovered without loss of activity. 相似文献
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Polymer-supported 4-aminoformoyldiphenylammonium triflate (PS-AFDPAT) was used as an effective catalyst for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) via the Biginelli reaction. This immobilized catalyst could be easily recovered by simple filtration and recycled for 10 runs without significant decrease of the catalytic activity. 相似文献
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Santosh Kumar Giri Monika Verma K. P. Ravindranathan Kartha 《Journal of carbohydrate chemistry》2013,32(8-9):464-478
Indium(III) trifluoromethanesulfonate has been found to be extremely efficient in catalyzing acyl transfer reactions of various carbohydrates and their derivatives. Selective acetolyses of certain benzyl ethers/isopropylidene acetals of sugars have been possible using In(OTf)3 in Ac2O (neat). Reaction of the per-O-acetate of 2-deoxy-2-phthalimido-D-glucose with benzyl mercaptan in the presence of In(OTf)3 led to the formation of the corresponding thioglycoside in high yield. Facile formation and hydrolysis of the isopropylidene and benzylidene acetals of various carbohydrates have also been achieved very efficiently in the presence of In(OTf)3. The results show great promise for In(OTf)3 in synthetic carbohydrate chemistry. 相似文献
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Various biologically important perimidine derivatives have been efficiently synthesized in excellent yields using naphthalene‐1,8‐diamine with various ketones in the presence of a catalytic amount of Yb(OTf)3. The influence of the loading of Yb(OTf)3, reaction solvent, the structure of ketones was studied. This method is a very easy, simple and high yielding reaction for the synthesis of perimidine derivatives. 相似文献
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Jia-Qi Wu Xin-Yuan Wu Dr. Jian-Mei Lu Prof. Dr. Qian Shi Dr. Li-Xiong Shao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202202441
In this study, a novel La(III)-based two-dimensional (2D) metal-organic framework, [La2/3(qptca)1/2] (referred to as SLX-2), from LaCl3 and 1,1′ : 4′,1′′ : 4′′,1′′′ : 4′′′,1′′′′-quinquephenyl]-2,2′′,2′′′′,5′′-tetracarboxylic acid (H4qptca) was synthesized by conventional solvothermal method and thoroughly characterized by using X-ray single-crystal diffraction, powder X-ray diffraction, and thermogravimetric analyses. The 2D SLX-2 features a unique lanthanum center exposed to the skeleton and was used as an efficient Lewis acid catalyst for the Friedel-Crafts alkylation of indole and pyrrole with β-nitrostyrene along with a wide substrate scope, giving the desired products in good-to-high yields under the optimal reaction conditions. Furthermore, the catalyst was used for twenty cycles, with nearly no effect on its activity, and the reaction was heterogeneous in nature. Moreover, compared to the previous hydrogen-bond-donating MOF catalysts for such alkylation reactions, SLX-2 showed an excellent stability toward harsh acidic and basic environment, and gave comparable catalytic activities. 相似文献
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A cost-effective and environmentally compliance FeCl3·6H2O catalyzed Friedel-Crafts alkylation of cyclic ketene dithioacetals with alcohols was developed. The reaction was efficient in the presence of catalyst loading as low as 5%(molar fraction) in CH2Cl2 solvent at room temperature or under reflux conditions. A wide range of alkylated ketene dithioacetals were synthesized in excellent yields. 相似文献
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The Friedel-Crafts alkylation of indoles with nitroacrylates could provide α- and β-tryptophan nitro-precursors, respectively, in moderate to good yields under Lewis acid catalysis. The diastereoselectivities of the reaction were enhanced by using 2-substituted indoles. The alkylation products could be easily transformed to nonnatural tryptophan derivatives. 相似文献
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A series of simple and new C2-symmetric diphenylmethylidene malonate-type bis(oxazoline) ligands were synthesized and applied to the Friedel-Crafts reaction and allylic alkylation. The Cu(II) complex of ligand 4b bearing the benzyl group afforded good to excellent enantioselectivity for the F-C adducts (up to >99% ee) between indole and alkylidene malonate, and the palladium complex of ligand 4c bearing the phenyl group afforded excellent enantioselectivity (up to 94% ee) for the allylic alkylation product. 相似文献