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1.
Atsushi Moroda  Hideo Togo   《Tetrahedron》2006,62(52):12408-12414
Biphenyl- and terphenyl-based recyclable trivalent iodine reagents, such as 4-bromo-4′-(diacetoxyiodo)biphenyl, 4,4′-bis(diacetoxyiodo)biphenyl, 1,4-bis[4-(diacetoxyiodo)phenyl]benzene, 4-bromo-4′-[(hydroxy)(tosyloxy)iodo]biphenyl, 4,4′-bis[(hydroxy)(tosyloxy)iodo]biphenyl, were simply prepared and their reactivities for the oxidative rearrangement of ketones to esters, TEMPO-mediated oxidation of alcohols to aldehydes or ketones, oxidative dealkylation of N-alkylsulfonamides to sulfonamides, and α-tosyloxylation of ketones were compared with p-(diacetoxyiodo)toluene and p-[(hydroxy)(tosyloxy)iodo]toluene to show the same reactivities and, moreover, the biphenyl- and terphenyl-based iodoarenes formed were recovered by simple filtration of the reaction mixture in every reaction. Thus, these biphenyl- and terphenyl-based trivalent iodine reagents can be used as the recyclable reagents.  相似文献   

2.
A homogeneous catalyst, 3-benzyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium chloride, for addition of aldehydes to activated double bond, was attached to 20% cross-linked polystyrene-divinylbenzene copolymer. The attached catalysts could be easily removed from the reaction mixture. Polymer-attached thiazolium salts in the presence of triethylamine are active catalysts for addition of aromatic and aliphatic aldehydes to α,β-unsaturated ketones to yield γ-diketones.  相似文献   

3.
In the presence of base, 3-subslituted 4-fonnyl- and 4-acetylsydnones decarbonylated to afford the corresponding 3-substituted sydnones. The Claisen-Schmidt reaction occurred between 3-substituted 4-for-mylsydnones and methyl ketone (such as 4-acetylsydnones, acetone and acetophenone) in dilute basic solution or electrogenerated basic (EGB) solution.  相似文献   

4.
1 INTRODUCTION Phthalimide and its derivatives are synthetic mate- rials, which are widely used as important chemical intermediates of biosensors[1] and many drugs such as Citalopran[2], luminal[3], Beta-Lactam[4] and the No. three generation quinolones[5], and they have been identified as active groups of some drugs and chemical luminescence reagents[6, 7]. Tert-butyl 4- [(E)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1- butenyl] benzoate is an intermediate of a new type of insulin sen…  相似文献   

5.
Under various basic solutions and reaction durations, 3-substituted 4-formyIsydnones and nitroalkanes containing α-active hydrogen (e.g. nitromethane and nitroethane) are converted to β-nitroalcohols, nitroalkenes and dinitroalkanes. β-Nitroalcohols are obtained only by electrochemical reaction on an electrogenerated base (EGB). The mechanism of overall reaction steps in particular is discussed.  相似文献   

6.
以广西的优势资源松香为原料, 脱氢松香酸与亚硫酰氯、硫氰化钾分别在回流条件下反应6 h和1.5 h, 得到脱氢松香酰异硫氰酸酯, 产率52%; 然后与胺在加热回流条件下反应1.5 h, 得到11种1-脱氢松香酰基-3-取代硫脲4, 产率63%~94%; 4a~4f 分别与水合肼在搅拌下回流反应3~6 h, 得到6种5-(脱羧脱氢松香-4-基)-3-芳氨基-1H-1,2,4-三唑化合物5, 产率70%~94%; 所有化合物的结构均经IR, 1H NMR, 13C NMR和元素分析确认. 初步生物活性测试表明, 4e, 4f, 4j, 5b对枯草杆菌抑菌率较高, 特别是4j在浓度为50 mg/L时就达到较好效果; 4b, 4h, 4i, 5e在100 mg/L时对大肠杆菌的抑菌效果较好.  相似文献   

7.
Two new 3D coordination polymers, [Tl210-CSB)] n (1) [CSB?=?4-[(4-carboxyphenyl)sulfonyl]-1-benzenecarboxylate] and [Tl29-ADC)] n (2) [ADC?=?acetylendicarboxylate], have been synthesized and characterized by elemental analysis, and IR spectroscopy. Thermal behavior and structures of 1 and 2 have been studied. Single-crystal X-ray data of 1 show that the thallium atoms have an irregular coordination sphere containing a stereochemically active lone pair with TlO5 environment. The single-crystal X-ray data of 2 showed that there are two different Tl environments. One Tl is six-coordinate with a weak Tl?···?Tl interaction with a distance of 3.904?Å. The other type of Tl in the TlO5C2Tl units is eight-coordinate with one weak Tl?···?Tl and two short Tl?···?C interactions.  相似文献   

8.
From the hexane extractive of the nutmeg of Myristica fragrans Houtt, glyceryl trimyristate (1), myristicin (11), methyleugenol (12), elemicin (13), dehydrodiisoeugenol (9), 1-(3,4,5-trimethoxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy)-propan-1-ol (4), 1-(3,4-methylenedioxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy)-propan-1-ol (6), and a new compound 1-(3,4-dimethoxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy) propan-1-ol (14) were isolated. The structure of compound (14) was determined to be an analogue of the β-0-4 ether type of dilignols.  相似文献   

9.
3-(3′-,4′-Hydroxyphenyl)sydnones were prepared by dealkylation of 3-(3′-,4′-alkoxyphenyl)sydnones with concentrated sulfuric acid at room temperature in a range of 59 to 86% yield.  相似文献   

10.
In the presence of triethylamine, 3-arylsydnone-4-carbohydroximic acid chlorides react not only with active methylene compounds containing keto groups to give 3-aryl-4-(4′,5′-disubstituted-isoxazol-3′-yl)sydnones, but also with compounds containing cyano groups to produce 3-aryl-4-(4′-substituted-5′-aminoisoxazol-3′-yl)sydnones or 3-aryl-4-(4′-cyano-5′-substituted-isoxazol-3′-yl)sydnones.  相似文献   

11.
3-烷基-6-芳氧亚甲基均三唑并[3,4,-b]-1,3,4-噻二唑的合成   总被引:8,自引:0,他引:8  
在POCl~3存在下,3-烷基-4-氨基-5巯基-1,2,4-三唑分别同植物生长激素2,4-二氯苯氧乙酸和β-萘氧乙酸缩合得到了12个新的化合物. 化合物的结构经元素分析,IR,^1H NMR , 以及MS等方法确证.初步生物测定实验表明,其中某些产物具有调节植物生长和抑制植物病原菌的作用.  相似文献   

12.
A variety of novel 5-[( Z )-arylidene]-2-[(2-( E )-arylidene)hydrazono]-4-imidazolidinones 1a-c to 4a , b and 5-[( Z )-arylidene]-2-[(2-( E )-polyhydroxyalkylidene)hydrazono]-4-imidazolidinones 5a-c to 7a-c were prepared from the reaction of 5-[( Z )-arylidene]-2-methylmercaptohydantoins 8a-c with 2-( E )-arylidene hydrazones 13a-d and/or 2-( E )-monosaccharides hydrazones 16a-c . The linear structure, and not that of the angular isomer, has been selected for the products. This structure has been confirmed from a model study of the condensation of 5-[( Z )-2-thienylidene]-2-hydrazono-4-imidazolidinone 9a with benzaldehyde and D -galactose, respectively. The acetylation and benzoylation reactions of compounds 1-7 have been studied. All the new compounds were tested for their potential antiviral and antitumor activities.  相似文献   

13.
Propyl O-(α-L-rhamnopyranosyl)-(1→3)-[2,4di-O-(2s-methylbutyryl)-α-L-rhamnopyranosyl]-(1→2)-(3-O-acetyl-β-glucopyranosyl)-(1→2)-β-D-fucopyranoside (1), the tetrasaccharide moiety of Ricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D-Glucose. The isomerization of the dioxolane-type benzylidene in the prance of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.  相似文献   

14.
Photochemical Reactions of Cyclopentadienylbis(ethene)rhodium with Phenanthrene, Acenaphthylene, and Triphenylene, and Unusual H Exchange between η2-Coordinated Phenanthrene or Acenaphthylene and η5-Cyclopentadienyl Ligands During UV irradiation of [CpRh(C2H4)2] (Cp = η5-C5H5) in hexane/ether in the presence of phenanthrene one ethene ligand is displaced by coordination of the 9,10 double bond of phenanthrene, and (η5-cyclopentadienyl) (η2-ethene)(η2-9,10-phenanthrene)rhodium ( 1 ) is formed. The analogous reaction in hexane in the presence of acenaphthylene occurs with formation of the complexes (η2-1,2-acenaphthylene)(η5-cyclopentadienyl)(2-ethene)rhodium 2 and bis(η2-1,2-acenaphthylene)(η5-cyclopentadienyl)rhodium 3 in which one and two ethene molecules of [CpRh(C2H4)2], respectively, are substituted by η2-1,2-acenaphthylene. The irradiation of [CpRh(C2H4)2] with triphenylene in hexane yields the compounds [CpRh(η4-1,2,3,4-triphenylene)] ( 4 ), [(CpRh)2(μ-η3: η3-triphenylene)] ( 5 ), and [(CpRh)332: η2: η2-triphenylene)] ( 6 ). Despite the partially very low yields the new complexes could be unequivocally characterized spectroscopically and in the case of 1 and 3 by X-ray structural analysis. The compounds 1 and 2 in solution reveal a novel dynamic behaviour; via an intramolecular C? H activation, exchange occurs between the protons of the η2-coordinated arene and the Cp ligand. The complex 4 in solution is fluxional, too.  相似文献   

15.
3-(Phenylthio)-4-(trimethylsilyl)-3-sulfolene (2) was readily prepared by chlorosulphenylation-dehydrochlorination of 3-(trimethylsilyl)-3-sulfolene (4b) . Treatment of 2 with n-butyllithium at ?105 °C followed by an alkylating agent gave only C5 alkylation products 6 demonstrating the stronger carbanion stabilizing ability of phenylthio group than that of trimethylsilyl group. 2-(Phenylthio)-3(trimethylsilyl)-1,3-butadiene (3a) was readily prepared by thermal extrusion of sulfur dioxide from 2 . Selective oxidation of 3a with MCPBA gave the sulfinyl (3b) and sulfonyl (3c) derivatives. The Diels-Alder reactions of 3a-c were studied, and the regiocontrolling power of the substituents follows the order PhS >PhSO ~ PhSO2 >Me3Si.  相似文献   

16.
A series of α-, β,β-, and α,β,β-deuterium-labelled acrylonitrile monomers were prepared and polymerized. Secondary deuterium isotope effects on the polymerization and on the pyrolysis reactions that precede carbon fiber formation were observed. When deuterium is in the α-position, the polymerization rate is greater and the molecular weight is higher. It is proposed that either the propagation rate constant or both that constant and the termination rate constant are increased on deuterium substitution. In differential scanning calorimetry, the polyacrylonitrile exotherm occurs at higher temperatures and is narrower when deuterium is substituted at the α-position. On the other hand, the thermal gravimetric analysis activation energy for weight loss of polymer at temperatures below the acrylic exotherm is lower when deuterium is in the α-position, relative to the α-hydrogen polymers. As there is no correlation between the weight loss energy of activation and the various exotherm parameters, the weight loss energy of activation and the various exotherm parameters, the weight loss and exotherm are considered to be independent events. Examination of the distribution of deuterium substituted ammonia species evolved during 100–240°C thermal treatment of the α-and β, β-deuterated polyacrylonitriles provides a clear indication that both the α- and β-positions are directly involved in hydrogen migration to nitrogen, but the mechanism of ammonia generation remains unclear. © 1995 John Wiley & Sons, Inc.  相似文献   

17.
A simple and efficient in situ synthesis of 4-[(4-methylpiperazin-1-yl)methyl]benzoic acid through direct reductive alkylation of 1-methylpiperazine in the presence of triacetoxy sodium borohydride in 95-99% yields is elaborated. The process is easy to scale-up for the large-scale synthesis of 4-[(4-methylpiperazin-1-yl)methyl]benzoic acid as the key synthetic intermediate of imatinib. This method was used for the synthesis of benzyl derivatives of heterocyclic amines in 87-90% yields.  相似文献   

18.
The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl-1-phenyl-1H-pyra-zol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1 with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6) , α = 112.566(1), β = 92.324(2), γ = 102.91(1)o, V = 1315.65(10) 3, Z = 2, Dc = 1.344 g/cm3, μ(MoKα) = 0.282 mm-1, λ = 0.71073 , F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra-and intermolecular C(12)-H(12)···O(1) and C(28)-H(28)···O(1)#1 hydrogen bonds were observed in the title compound.  相似文献   

19.
研究了2-苯基-1, 2, 3-三唑-4-羧酸(1)与3-烷基/芳基-4-氨基-5-巯基-1, 2, 4-三唑(2a~o)在POCl~3催化下, 脱水缩合得到15个新的3-烷基/芳基-6-(2'-苯基-1', 2', 3'-三唑-4'-基)均三唑并[3,4-b]-1, 3, 4-噻二唑类化合物(3a~o)。  相似文献   

20.
以3,5-二甲基苯胺和2-莰酮为起始原料,在微波促进下,经缩合反应制得N-(3,5-二甲基苯基)-1-(1S,4S)-1,7,7-三甲基二环[2.2.1]庚烷-2-亚胺(1);1经硼氢化钠还原后再与羟胺-O-磺酸经胺化反应合成了1-(3,5-二甲基苯基)-1-[(1S,4S)-1,7,7-三甲基双环[2.2.1]庚烷-2-基]肼,总收率70.4%,其结构经1H NMR和ESI-MS确证。  相似文献   

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