- Exhaustive One-Step Bridgehead Methylation of Adamantane Derivatives with Tetramethylsilane
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A methylation protocol of adamantane derivatives was investigated and optimized using AlCl3 and tetramethylsilane as the methylation agent. Substrates underwent exhaustive methylation of all available bridgehead positions with yields ranging from 62 to 86 %, and up to six methyl groups introduced in one step. Scaling-up of the reaction was demonstrated by performing the >40 gram-scale synthesis of 1,3,5,7-tetramethyladamantane with 62 % yield. For several substrates, rearrangements were observed, as well as cleavage of functional groups or Csp3?Csp2 bonds or even cyclohexyl-adamantyl bonds. Based on mechanistic studies, it is suggested that a reactive methylation complex is formed from tetramethylsilane and AlCl3. X-ray diffraction structures of hexamethylated bis-adamantyls reveal elongation or widening of sp3 carbon bonds between adamantyl moieties to 1.585(3) ? and 125.26(9)° due to repulsive H???H contacts.
- Bonsir, Maxime,Davila, Christian,Geerts, Yves,Kennedy, Alan R.
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supporting information
p. 5227 - 5237
(2021/10/19)
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- IDO inhibitor compound, pharmaceutical compound and application
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The invention provides a novel compound. The compound has certain inhibiting activity to indoleamine 2, 3-dioxygenase (IDO) and can be possibly used for treating diseases related to the indoleamine 2, 3-dioxygenase (IDO).
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Paragraph 0053; 0060; 0061; 0062
(2017/09/29)
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- Peculiar Features of the Willgerodt–Kindler Reaction of 1-Adamantylpropan-2-one and Its Derivatives
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The Willgerodt–Kindler reaction of 1-(1-adamantyl)propan-2-one and its derivatives was studied by gas chromatography–mass spectrometry. The reaction time was found to be 3–4 times longer than in the case of alkyl aryl ketones due to considerable steric hindrances in the molecules of adamantyl ketones. The use of diglyme as solvent and sodium butyl xanthate as catalyst significantly shortened the reaction time and improved the yield to 92%.
- Novakov,Orlinson,Savel’ev,Potaenkova,Vostrikova,Tarakanov,Nakhod
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p. 2762 - 2765
(2018/02/21)
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- Synthesis of 1-(2-oxopropyl)adamantane from 1-bromo(chloro)adamantanes and isopropenyl acetate in the presence of iron and manganese compounds
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An efficient procedure has been developed for the synthesis of 1-(2-oxopropyl)adamantane by reaction of 1-bromo(chloro)adamantanes with isopropenyl acetate in the presence of manganese and iron compounds.
- Khusnutdinov,Shchadneva,Kislitsina,Veklov,Kutepov
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p. 1272 - 1275
(2015/01/08)
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- InI3/me3sii-catalyzed direct alkylation of enol acetates using alkyl acetates or alkyl ethers
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A combined Lewis acid of InI3 and Me3SiI was used to catalyze the direct coupling reactions of enol acetates with alkyl acetates or alkyl ethers without generating metal waste. The easily-handled alkylating reagents enlarged the application area of this coupling reaction. 2011 The Chemical Society of Japan.
- Onishi, Yoshiharu,Nishimoto, Yoshihiro,Yasuda, Makoto,Baba, Akio
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supporting information; experimental part
p. 1223 - 1225
(2011/11/29)
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- InCl3/Me3SiBr-catalyzed direct coupling between silyl ethers and enol acetates
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A combined Lewis acid catalyst of InCl3 and Me3SiBr promoted the direct use of enol acetates in the coupling with low-reactive silyl ethers, in which functional groups including ketones and aldehydes survived. Sterically hindered silyl ethers such as ROSiEt3, ROSiPh3, ROSit-BuMe2, and ROSii-Pr3 were also applicable.
- Onishi, Yoshiharu,Nishimoto, Yoshihiro,Yasuda, Makoto,Baba, Akio
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p. 2762 - 2765
(2011/08/02)
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- α-Alkylation of carbonyl compounds by direct addition of alcohols to Enol acetates
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A practical α-alkylation of ketones and aldehydes has been achieved by the direct addition of alcohols to enol acetates. The moderate Lewis acidity of InI3, CaBr3, and FeBr3 is a key factor in the catalytic cycle, and many different alcohols and enol acetates have been successfully used in this procedure.
- Nishimoto, Yoshihiro,Onishi, Yoshiharu,Yasuda, Makoto,Baba, Akio
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supporting information; experimental part
p. 9131 - 9134
(2010/03/01)
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- Asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens
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A new asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens has been found. Although alcohols are not the natural substrates for this enzyme, a high R enantioselectivity was observed. Stereochemical studies showed that variations in substrate structure lead to strong variations in enantioselectivity. The highest enantioselectivities are obtained when the β-carbon of the secondary alcohol is tertiary or quaternary.
- Hatzakis, Nikos S.,Smonou, Ioulia
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p. 325 - 337
(2007/10/03)
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- Evidence that the availability of an allylic hydrogen governs the regioselectivity of the Wacker oxidation
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The allylic hydrogen is found to have a dramatic effect on the regioselectivity of the Wacker oxidation, leading to the postulation that an agostic hydrogen or enyl (σ + π) complex helps to stabilise the key intermediate.
- Gaunt,Yu,Spencer
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p. 1844 - 1845
(2007/10/03)
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- Reactivity of 1-Iodoadamantane with Carbanions by the SRN1 Mechanism
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The photostimulated reaction of 1-iodoadamantane (1) with carbanions in DMSO has been studied.Acetone enolate ion (2a) reacted with 1 to give the substitution product (4a, 20percent) and adamantane (3, 17percent); acetophenone enolate ion (2b) gave the substitution product (4b, 65percent) in the presence of 18-crown-6.In the reaction with propiophenone enolate ion (2c), the yield was lower (27percent).Anthrone anion (5) gave good yields (75percent) of the substitution product 6.The anion of nitromethane (7) did not react with 1 under photostimulation, but in the presence of 2a or b, 87percent of 1-adamantylnitromethane (8) was obtained (entrainment reactions).Low amounts of substitution products were found with the fluorene anion and no substitution was observed with other carbanions.It is suggested that these reactions occurred by the SRN1 mechanism.By competition experiments, the following reactivity order toward 1-adamantyl radicals was determined: 2a (1.0) a of the conjugate acid of the anions and on the changes in ? energy (HOMO carbanion - SOMO radical anion intermediate) that takes place in the coupling reaction.By competition experiments of 1 and PhI toward 2b, a k1:KPhI ratio of ca. 16 was found while 1-bromoadamantane and PhBr gave a k1-BrAd:kPhBr ratio of ca. 0.13.This difference can be attributed to the capacity of phenyl radicals to abstract iodine atoms from 1 giving PhI and 1-adamantyl radicals, which ultimately results in an apparent greater reactivity of 1 vs.PhI.
- Rossi, Roberto A.,Pierini, Adriana B.,Borosky, Gabriela L.
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p. 2577 - 2582
(2007/10/02)
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- The Photostimulated Reaction of 1-Iodoadamantane with Carbanionic Nucleophiles in DMSO by the SRN1 Mechanism
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1-Iodoadamantane (1) reacts under irradiation with the enolate ions of acetone (2), acetophenone (5a), and propiophenone (5b) to give adamantane and the substitution products in variable yields.The anion of nitromethane (7) does not react under irradiation with 1, but excellent yields of 1-adamantylnitromethane (8) are obtained in the photostimulated reaction of 1 and 7 in the presence of 2 or 5a (entrainment reactions).We suggest that 1-iodoadamantane reacts with these nucleophiles by the SRN1 mechanism of nucleophilic substitution.
- Borosky, Gabriela L.,Pierini, Adriana B.,Rossi, Roberto A.
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p. 3705 - 3707
(2007/10/02)
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- REACTION OF ORGANOMAGNESIUM COMPOUNDS OF THE ADAMANTANE SERIES WITH CARBONYL COMPOUNDS
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In the transformations of organomagnesium compounds of the adamantane series involving aldehydes, ketones, esters, and acid chlorides the nature of the reaction products and their yields are determined by the steric hindrances at the reaction centers of the organomagnesium and carbonyl compounds and by the ease of homolysis of the C-H bonds of the carbonyl reagent.The retardation of the faster addition of the Grignard reagent at the carbonyl group as a result of steric hindrances permits homolytic removal of a hydrogen atom from the carbonyl compounds by the adamantyl radical.
- Yurchenko, A. G.,Fedorenko, T. V.
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p. 875 - 880
(2007/10/02)
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- Structure-Anti-Parkinson Activity Relationships in the Aminoadamantanes. Influence of Bridgehead Substitution
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A limited series of bridgehead alkyl-, dialkyl- and trialkyl-substituted amantadines was synthesized and tested for potential anti-Parkinson activity as dopamine (DA) agonists.The compounds were evaluated using a battery of three murine bioassays, including stimulation of locomotor activity, induction of circling in animals with unilateral striatal lesions, and reversal of reserpine/α-methyltyrosine induced akinesia.Apparent mechanistic differences were seen between the methyl-substituted series and the ethyl-substituted series.While activities in both series increase with increasing liphophilicity, the methyl series (1b-d), as well as amantadine itself (1a) exhibits only indirect DA agonist activity, as evidenced by ipsilateral rotation in the circling model and no significant difference from control in reversal of akinesia.The ethyl series (1e,f) exhibits weak but reprodicible direct DA agonist activity, as shown by contralateral rotation in the circling assay for 1e and reversal of akinesia by 1e and 1f.The 3-n-propyl derivative (1g) was devoid of any DA agonist activity.
- Henkel, James G.,Hane, Jeffrey T.,Gianutsos, Gerald
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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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- Anorectic adamantane derivatives and method of using the same
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Adamantane derivatives such as β-(1-adamantyl)-α,α-dimethylethylamine hydrochloride, β-(1-adamantyl)-α-methylethylamine hydrochloride, d-β-(1-adamantyl)-α-methylethylamine hydrochloride, and 1-β-(1-adamantyl)-α-methylethylamine hydrochloride have anorectic activity. The hydrazine derivatives of the above compounds are antihypertensive agents, and monoamine oxidase inhibitors.
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