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1.
Alkylation of pyrazoles with 2-chloroethylamine was performed under conditions of phasetransfer catalysis. Depending on the substrate acidity, the electrophilic substitution process may be accompanied by dehydrochlorination of the alkylating agent, so that 6 equiv of 2-chloroethylamine should be used in the alkylation of 3,5-dimethylpyrazole.  相似文献   

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Abstract

Condensation of indole with aromatic aldehydes has been carried out without using any catalyst and solvent to give bis(indolyl)methanes.  相似文献   

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2-Ferrocenylpropan-2-ol was synthesized by addition of ferrocene to acetone in the two-phase system petroleum ether-water using H2SO4-DEANaph as catalyst. Study on the kinetic parameters of the process showed that during the first two hours (conversion 87%) the reaction is of first order in ferrocene. The energy of activation of the addition of ferrocene to acetone under conditions of phase-transfer catalysis was estimated at 21 kcal mol−1.  相似文献   

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Heating of (1S,3S)-3-acetoxymethyl-1-(2-acetoxyvinyl)-2,2-dimethylcyclopropane with bromoform under phase-transfer catalysis affords dibromocyclopropane viaaddition of dibromocarbene to the double bond. In an analogous reaction with chloroform, the trichloromethyl anion adds to the double bond in the -position with respect to the acetoxy group.  相似文献   

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Mallappa Beerappa 《合成通讯》2018,48(17):2150-2158
A facile synthesis of a series of pyrimidinone derivatives from the reaction of benzyl halides, (1-bromoethyl)benzene and urea in the presence of pyridine N-oxide (PNO) under solvent-free conditions is described. This transformation presumeably occurs via oxidation/cross-aldol condensation/Michael addition/intra molecular cyclization, domino sequence, involving the formation of one C–C bond and two C–N bonds in a single step.  相似文献   

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Cyclododecanone is readily alkylated with benzyl halides (ArCH2X) to give 2-benzylcyclododecanones under conditions of phase transfer catalysis. Under the action of polyphosphoric acid 2-benzylcyclododecanone undergoes cyclization to give 1,2,3,4,5,6,7, 8,9,10-decahydrocyclododeca[b]indene. It also reacts with NOCl to give 12-hydroxyimino-2-benzylcyclododecanone, which enters the Beckmann rearrangement to afford 2-benzyl-1,12-dodecandioic acid.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 905–907, May, 1993.  相似文献   

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The reaction of tris(trimethylsilyl) phosphite with aryl bromides under homogeneous catalysis conditions gives bis(trimethylsilyl)arylphosphonates. The desilylation of these phosphonate products with methanol leads to arylphosphonic acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1461–1462, June, 1991.  相似文献   

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The tosylation of oleyl alcohol under the conditions of phase-transfer catalysis has been studied. In this process oleyl p-toluenesulfonate of formed with a yield of up to 80%.Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, 443–445, May–June, 1988.  相似文献   

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Conformationally constrained cyclic alpha-amino acid derivatives were synthesized under solid-liquid phase-transfer catalysis conditions. This methodology involves the bis-alkylation of ethyl isocyanoacetate with various alpha,alpha'-dibromo-o-xylene derivatives [alpha,alpha'-dibromo-o-xylene 5, 2,3-bis(bromomethyl)-1, 4-dimethoxybenzene 6, 1,2-bis(bromomethyl)-4,5-dibromobenzene 7, 2, 3-bis(bromomethyl)naphthalene 8, 1,8-bis(bromomethyl)-naphthalene 9, 6,7-bis(bromomethyl)-2,2-dimethyl-1H-phenalene-1,3(2H)-dione 10, 2, 3-bis(bromomethyl)-1,4-anthraquinone 11, 6, 7-bis(bromomethyl)quinoxaline 12, 3,4-bis(bromomethyl)furan 13, 1,2, 4,5-tetrakis(bromomethyl)benzene 28, and hexakis(bromomethyl)benzene 30] using potassium carbonate as a base and tetrabutylammonium hydrogensulfate as a phase-transfer catalyst to give corresponding isonitrile derivatives, which upon hydrolysis with HCl in ethanol gave amino esters. Using this method electron-deficient as well as electron-rich and halogen-substituted indan-based alpha-amino acids were prepared. The preparation of bis-indan as well as tris-indan alpha-amino esters is also described.  相似文献   

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以2-氯吡啶(1)、2-甲氨基乙醇(2)和4-氟苯甲醛(4)为主要原料,经2步反应合成了4-{2-[N-甲基-N-(2-吡啶基)氨基乙氧基]}苯甲醛(5).第1步反应n(2)∶n(1)=4∶1,反应温度160℃,反应时间约6h,采用减压蒸馏进行后处理,2-[N-甲基-N-(2-吡啶基)氨基]乙醇(3)的收率在93%以上,过量2的回收率在97%以上,回收的2可以重复使用.第2步反应用氢氧化钠做碱性试剂,用甲苯和水分别做为两相的溶剂,在相转移催化剂CTAB作用下进行,经优化后5的收率可达90%以上.2步反应总收率达83%以上.  相似文献   

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Arylation of 1H-1,2,3-benzotriazole, with activated aryl halides in a medium of aromatic hydrocarbons under conditions of phase transfer catalysis with the use of inorganic bases and cetyltrimethylammonium bromide as a phase-transfer catalyst was studied. Arylation affords bothN(1)- andN(2)-arylation products. Their ratio depends on the nature of the base and the reactivity of the arylating agent. In the presence of catalytic amounts of copper phenylcyclopropanecarboxylate, arylation proceeds regioselectively at the N(1) atom. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1553–1556, August, 1999.  相似文献   

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Symmetrical and non-symmetrical substituted bis(3,4-dihydro-1-isoquinolyl)methanes were synthesized by fusion of substituted 1-methylthio-3,4-dihydroisoquinolines with 1-methyl-3,4-dihydroisoquinolines and by the Ritter reaction of 1,1-dialkyl-2-arylethanols with 1-cyanomethylidene-1,2,3,4-tetrahydroisoquinoline or malononitrile.  相似文献   

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Phase-transfer catalysis (PTC) is a widely accepted methodology in organic synthesis. Although a great number of organic syntheses were reported in PTC conditions, systematic kinetic studies are scarce. In the present report, a detailed study of the kinetics of the reaction between 2-chloro-5-nitrotrifluoromethylbenzene (CNTFB) and 2-phenylpropionitrile anion (HPP-), under PTC, was performed under several conditions. The reaction was carried out either in toluene or chlorobenzene as the organic phase, in the presence of a concentrated aqueous solution of NaOH using tetraalkylammonium (Q+X-) salts as phase-transfer catalysts. The major product was 2-(4-nitro-2-trifluoromethylphenyl)-2-phenylpropionitrile, and its yield depends on the experimental conditions. Different aspects of the mechanism are discussed and quantified. Kinetic data were explained by means of an interfacial mechanism that involves the deprotonation of the adsorbed nucleophile precursor followed by its catalyst-mediated extraction to the organic phase. A multicomponent Langmuir-type interface was assumed. Although the extraction of OH- by catalyst to the organic phase is usually disregarded, the formation of the substrate hydrolysis product that leads to catalyst poisoning was also investigated. The influence of this side reaction on the yield of the main product was established. A discussion about the influence of this side process on the main reaction and the operating mechanism is presented.  相似文献   

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