- An effective formylation of adamantane with CO initiated by the aprotic organic superacid CBr4·2AlBr3 under mild conditions
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The reaction of adamantane with carbon monoxide at -45°/+20°C over 0.5-2 h, catalyzed by the aprotic organic superacid CBr4·2AlBr3, is described. The formylation of adamantane under CO atmosphere at 0/+20°C in the presence of methylcyclopentane as a source of hydride ion affords 1-adamantanecarbaldehyde (1) in yield 70-72% on adamantane for 1 h.
- Akhrem, Irena,Churilova, Irina,Bernadyuk, Stanislav,Vol'pin, Mark
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- Synthesis and study of properties of azoles and their derivatives - Communication 22. Syntheses based on 1-adamantanecarbonitrile
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1. 1-Adamantanecarbonitrile reacts with alcohols and hydrogen chloride with greater difficulty than do aliphatic nitriles to give the hydrochlorides of the imino esters of 1-adamantanecarboxylic acid, which are more stable than the corresponding compounds of the aliphatic series. 2. The hydrochloride of the methyl imino ester of 1-adamantanecarboxylic acid condenses with ethylenediamine, o-phenylenediamine and o-aminophenol in the usual manner to give the corresponding heterocyclic compounds. 3. The methyl imino ester of 1-adamantanecarboxylic acid when heated with ethanolamine gives the corresponding oxazoline. The hydrochloride of the methyl imino ester of 1-adamantanecarboxylic acid does not give the s-triazine when heated, and instead gives 1-adamantanecarbonitrile.
- Shvekhgeimer,Kuz'micheva,Novikov
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- Oxidation of Deactivated Cage Substrates in the System H2SO4–HNO3
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Abstract: The kinetics of oxidation of 16 carboxylic acid esters of the adamantaneseries in the systemH2SO4–HNO3have been studied, and the effective rate constants have been determined. Thereaction is described by the pseudo-first-order kinetic equation. The primarykinetic isotope effect has been estimated at 2.9±0.3. The rate-determining stepof the oxidation process is cleavage of the adamantane C–H bond. The presence ofan ethyl group at the bridgehead position increases the reactivity of adamantanesubstrates toward oxidation, whereas methyl, ethoxycarbonyl, andethoxycarbonylmethyl groups reduce the reactivity.
- Grin?, I. S.,Ivleva, E. A.,Klimochkin, Yu. N.,Uchaev, I. S.
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- Design, Synthesis, and in vitro Evaluation of P2X7 Antagonists
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The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide (56) exhibiting the best potency with an IC50 value of 0.39 μΜ.
- Durner, Anna,Koufaki, Maria,Kritsi, Eftichia,Nicke, Annette,Papakostas, Alexios,T. Pournara, Dimitra,Zoumpoulakis, Panagiotis
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supporting information
p. 2530 - 2543
(2020/10/19)
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- One-pot dichlorinative deamidation of primary β-ketoamides
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An approach to the dichlorinative deamidation of primary β-ketoamides through ketonic cleavage is described, and a series of α,α-dichloroketones were furnished mostly in the presence of TEMPO. Based on control experiments, a mechanism involving tandem dichlorination and deamidation is proposed to interpret the observed reactivity.
- Zheng, Congke,Zhang, Xiaohui,Ijaz Hussain, Muhammad,Huang, Mingming,Liu, Qing,Xiong, Yan,Zhu, Xiangming
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supporting information
p. 574 - 577
(2017/01/16)
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- One-pot transformation of carboxylic acids into nitriles
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A variety of aromatic and aliphatic carboxylic acids were smoothly converted into the corresponding nitriles in good yields in a one-pot procedure by treatment with ethyl iodide/K2CO3/18-crown-6, followed by sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), and finally treatment with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH), and aqueous ammonia. This method is useful for the conversion of various aromatic and aliphatic carboxylic acids into the corresponding nitriles in a one-pot procedure. A variety of aromatic and aliphatic carboxylic acids were smoothly converted into the corresponding nitriles in good yields in a one-pot procedure by treatment with ethyl iodide/K2CO3/18-crown-6, followed by sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), and finally treatment with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH), and aqueous ammonia. Copyright
- Miyagi, Kotaro,Moriyama, Katsuhiko,Togo, Hideo
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p. 5886 - 5892
(2013/09/23)
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- Reactions of O-quinone methides with pyridinium methylides: A diastereoselective synthesis of 1,2-dihydronaphtho[2,1- b ]furans and 2,3-dihydrobenzofurans
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A simple, general route to the 1,2-dihydronaphtho[2,1-b]furans and 2,3-dihydrobenzofurans substituted at C-2 by an acyl or aryl group, starting from phenolic Mannich bases and pyridinium ylides, has been developed. The mechanism of the reaction is believed to involve the formation of the o-quinone methide intermediate, Michael-type addition of the ylide to the o-quinone methide, followed by intramolecular nucleophilic substitution.
- Osyanin, Vitaly A.,Osipov, Dmitry V.,Klimochkin, Yuri N.
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p. 5505 - 5520
(2013/07/25)
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- Preparation of 1-adamantyl ketones: Structure, mechanism of formation and biological activity of potential by-products
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Reactions between adamantane-1-carbonyl chloride and several Grignard reagents as well as interactions with solvents have been examined. Some new and unexpected adamantane derivatives were isolated, fully characterized and their biological activity determined. In particular, an unexpected isochromanone 16 was formed in an SEAr process, in which a stable hydrocarbon was the leaving group.
- Vicha, Robert,Necas, Marek,Potacek, Milan
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p. 709 - 722
(2008/02/01)
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- Efficient esterification of carboxylic acids and phosphonic acids with trialkyl orthoacetate in ionic liquid
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An operationally simple, inexpensive, efficient, and environmentally friendly esterification of various carboxylic acids, phosphonic acids, and phosphinic acids with triethyl orthoacetate or trimethyl orthoacetate under neutral conditions in a typical room temperature ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, was successfully carried out to provide the corresponding ethyl esters or methyl esters in high yields.
- Yoshino, Tomonori,Imori, Satomi,Togo, Hideo
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p. 1309 - 1317
(2007/10/03)
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- Influence of catalytic system composition on formation of adamantane containing ketones
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The preparation of non-symmetrical ketones by the reaction of acyl chlorides and the corresponding Grignard reagents in the presence of catalytic amounts of metal halides is described. The composition of catalyst has a great influence on the yield of the required ketone as well as on side product formation. For each catalytic system, the yield of ketone and the number of side products changes with the time of addition of the Grignard reagent. We examined the influence of both factors in our model reaction of adamantane-1-carbonyl chloride with ethylmagnesium bromide and discussed the possible mechanisms from this point of view. We have found ZnCl2, MnCl2, AlCl 3 and CuCl to be active catalytic components and developed very efficient, cheap and fast methods for the preparation of alkyl adamantyl ketones. The procedure was also tested for the synthesis of other alkyl aryl ketones. Graphical Abstract.
- Vícha, Robert,Potá?ek, Milan
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- Environmentally friendly esterification of carboxylic acids with triethyl orthoacetate in ionic liquid
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An operationally simple, inexpensive, efficient, and environmentally friendly esterification of carboxylic acids with triethyl orthoacetate under neutral conditions in a typical room temperature ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, was carried out to provide the corresponding ethyl esters in high yields.
- Yoshino, Tomonori,Togo, Hideo
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p. 1604 - 1606
(2007/10/03)
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- Generation of alkyl hypochlorites in oxidation of alcohols with carbon tetrachloride catalyzed by vanadium and manganese compounds
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Primary alcohols and diols with various structures were subjected to transformations into esters, aldehydes, ketones, and lactones under the action of carbon tetrachloride in the presence of manganese compounds (MnCl 2, MnO2, Mn(OAc)2, Mn(acac)3) and vanadium compounds (VCl5, V2O5, VO(acac) 2) as catalysts. These transformation proceeded with the involvement of alkyl hypochlorites, which were generated in the course of oxidation of alcohols with carbon tetrachloride catalyzed by manganese or vanadium compounds. The optimum molar ratios between the catalyst and reagents were determined, and the reaction conditions for the highly selective synthesis of esters, aldehydes, ketones, and lactones from alcohols were found.
- Khusnutdinov,Shchadneva,Baiguzina,Lavrentieva,Dzhemilev
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p. 2074 - 2079
(2007/10/03)
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- Functionalization of saturated hydrocarbons by aprotic superacids 6. * Effective regioselective monoformylation of adamantane in the presence of a hydride ion donor
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The inefficient formylation of adamantane by CO initiated by superacid systems based on polyhalomethanes and aluminum halides becomes selective in the presence of methylcyclopentane and affords 1-adamantanecarbaldehyde in an almost quantitative yield under mild conditions.
- Akhrem,Churilova,Vitt,Orlinkov,Vol'pin
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p. 491 - 495
(2007/10/03)
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- Reaction enthalpy of nucleophilic substitution of ethyl iodide in acetonitrile and its mechanistic significance
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Enthalpies of reaction for nucleophilic substitution of ethyl iodide have systematically been determined in acetonitrile. Through the concurrent analysis of empirical correlations between the reaction enthalpies and the specific interaction enthalpies for relevant anions with those between the logarithmic rates and the specific interaction enthalpies, partial desolvation accompanying activation has been deduced to be the major contributor to activation thermodynamic parameters, while the propensity of the reacting central atom in the nucleophilic anion plays a crucial role in determining reaction thermodynamic parameters. Semi-empirical molecular orbital calculations have supported these ideas. The application of the Marcus equation to the analysis of reaction characteristics in these reactions is discussed.
- Kondo, Yasuhiko,Tsukamoto, Tamio,Kimura, Naoko
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p. 1765 - 1769
(2007/10/03)
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- Dual Reaction Channels for Solvolyses of Acyl Chlorides in Alcohol-Water Mixtures
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Rate constants are reported for solvolyses at 0 deg C of trimethylacetyl chloride (3) in 90-30percent v/v acetonitrile-, acetone-, ethanol- and methanol-water mixtures, of adamantane-1-carbonyl chloride (4) in 90-60percent acetone-, ethanol- and methanol-water mixtures, and of cyclopropanecarbonyl chloride (5) in 90-40percent acetone-water.Quantitative product data (acid and ester) are also reported for solvolyses of trimethylacetyl chloride in 98-20percent ethanol- and methanol-water mixtures.Product selectivities (S) show maxima in 90-95percent alcohol-water mixtures, similar to those, reported previously for solvolyses of p-chlorobenzoyl chloride (1a), benzoyl chloride (1b), 2,4,6-trimethylbenzenesulfonyl chloride (2a) and 4-methoxy-2,6-dimethylbenzenesulfonyl chloride (2b).Using rate-rate profiles, logarithms of rate constants are dissected into the competing reaction channels.Given the sharp maxima in S that occur at different alcohol compositions for different substrates, and the link to 'breaks' in rate-rate profiles, the results are consistent with competing mechanisms having different rate-limiting steps.The competing mechanisms involve two broad reaction channels: (1) nucleophilic attack by one molecule of solvent assisted by a second molecule of solvent acting as a general base catalyst-consequently, in aqueous alcohol there are four mechanistic combinations operating simultaneously within this one reaction channel; (2) nucleophilic attack by solvent occurs via a carbocationic reaction within the SN2-SN1 mechanistic spectrum, involving for example, a solvent-separated ion pair intermediate (SN1) or a concerted nucleophilic attack (SN2).
- Bentley, T. William,Shim, Chang Sub
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p. 1659 - 1664
(2007/10/02)
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- Investigations with Selective Deblocking Reagents for Adpoc-Protected Amno Acids and Peptides
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Selective reagents for the removal of the Adpoc group have been developed.For this purpose several peptides containing tryptophan and Nε-Boc-lysine have been synthesized.Among several acidolytic reagents, 0.1 N HCl/TFEt/CHCl3 (1:9:1) annd 50percent HCOOH/TFEt/CHCl3 (1:9:1) show high selectivity especially for the Nε-tert-butyloxycarbonyl group of lysine.Cleavage rates are determinned by HPLC and TLC. Key Words: Adpoc-protecting group / Protecting groups / Amino acids / Peptides / Kinetics
- Voelter, Wolfgang,Kalbacher, Hubert
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p. 131 - 136
(2007/10/02)
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- Nucleophilic Substitution Reactions of Aliphatic and Aromatic Carboxylate Ions with Ethyl Iodide. Specific Interactions and Isokinetic Relationships in Acetonitrile-Methanol Mixtures
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Transfer enthalpies for the transition-state anions in the reactions of the carboxylate anions adamantane-1-carboxylate, pivalate, benzoate, and 4-nitrobenzoate with ethyl iodide have been determined in acetonitrile-methanol mixtures (AN-MeOH).After the separation of these enthalpies into their constituent terms, i.e., physical interaction and specific interaction enthalpies, the number of methanol molecules hydrogen-bonded to the anion has been evaluated on the basis of the assumption that the isokinetic relationship is realized between activation parameters, which can be identified as physical interaction quantities.An empirical correlalation was observed between that number and the specific interaction enthalpy, ΔHAN->MeOHt,SI, for the anion.On the basis of the AM1 model calculations, discussion is given on the factors which affect the physical interaction enthalpy.
- Kondo, Yasuhiko,Fujiwara, Tadayuki,Hayashi, Akio,Kusabayashi, Shigekazu,Takagi, Tatsuya
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p. 741 - 746
(2007/10/02)
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- REACTION OF 1-ACETYLADAMANTANE WITH THIONYL CHLORIDE
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1-Acetyladamantane (I) reacts with thionyl chloride in the presence of pyridine to give 1-(1'-chloroethenyl)adamantane (IV).In the absence of pyridine, the same reaction affords amore complex mixture containing 1-adamantanecarboxylic acid (VI), its ethyl ester (VII), and 1-chloroacetyladamantane (V).
- Burkhard, Jiri,Janku, Josef,Vodicka, Ludek
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p. 110 - 113
(2007/10/02)
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- Synthesis of 1-adamantyl and 1-adamantylmethyl alkyl ketones
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The reaction of 1-adamantanecarboxylic and 1-adamantylacetic acids with Grignard reagents in the presence of cuprous chloride or iodide gave the corresponding ketones.
- Grava, I. Ya.,Polis, Ya. Yu.,Lidak, M. Yu.,Liepin'sh, E. E.,Shatts, V. D.,et al.
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p. 679 - 686
(2007/10/02)
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