- 1,3-Diaxial steric effects and intramolecular hydrogen bonding in the conformational equilibria of new cis-1,3-disubstituted cyclohexanes using low temperature NMR spectra and theoretical calculations
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The conformational equilibria of 3-X-cyclohexanol [X = F (1), Cl (2), Br (3), I (4), Me (5), NMe2 (6) and MeO (7)] and of 3-X- methoxycyclohexane [X = F (8), Cl (9), Br (10), I (11), Me (12), NMe2 (13) and MeO (14)] cis isomers were
- De Oliveira, Paulo R.,Rittner, Roberto
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- Trimethylchlorosilane and water. Convenient reagents for the regioselective hydrochlorination of olefins
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The hydrochlorination of a series of simple and functionalized olefins in high yields was readily accomplished using a mixture of trimethylchlorosilane and water. Hydrochlorination by this procedure is chemoselective and regioselective.
- Boudjouk, Philip,Kim, Beon-Kyu,Han, Byung-Hee
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- Method for preparing alicyclic ketone by catalytic oxidation of alicyclic alcohol compound
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The invention provides a method for preparing alicyclic ketone by catalytic oxidation of an alicyclic alcohol compound. The method takes air or oxygen as an oxidant and uses a catalyst system consisting two components of aza-adamantane free radical of nitroxide and a vanadium oxygen compound, and the alicyclic alcohol compound is oxidated into the corresponding alicyclic ketone with high selectivity at 50 to 120 DEG C. Compared with 2,2,6,6,-tetramethyl piperidine free radical of nitroxide, the aza-adamantane free radical of nitroxide has smaller influence of steric hindrance in a catalytic oxidation secondary alcohol reaction, and the catalyst system consisting of the vanadium oxygen compound has higher alicyclic alcohol oxidating efficiency. Compared with the conventional stoichiometric chemistry oxidation methods such as manganese dioxide, chromium trioxide and sodium hypochlorite, the method provided by the invention has the characteristics of few side products, mild reaction conditions, small environmental pollution and the like, and has very high practicability and economical efficiency.
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Paragraph 0029; 0030
(2016/12/01)
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- Acid-catalyzed reactions of six- and seven-membered cyclic hemiperacetals and peracetals and of related bicyclic ozonides
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HCl-catalyzed reactions of the hemiperacetals 3-methoxy-3-methyl-7-hydroxy-1,2-dioxepane (1a) and 3-methoxy-3-methyl-6-hydroxy-1,2-dioxane (1b) and of the related ozonides 1-methyl-6,7,8-trioxabicyclooctane (2a) and 1-methyl-5,6,7-trioxabicycloheptane (2b) gave peroxidic monocyclic (11-13), bicyclic (14), and (or) tricyclic (15) products.By contrast, reactions of the peracetals corresponding to 1a and 1b, viz., 3-methyl-3,7-dimethoxy-1,2-dioxepane (13a) and 3-methyl-3,6-dimethoxy-1,2-dioxane (13b) gave only non-peroxide products.Reactions of the persubstituted peracetals 3,6-dimethoxy-3,6-dimethyl-1,2-dioxane (25) and 3,6-dimethoxy-3-isopropyl-6-methyl-1,2-dioxane (27) also gave non-peroxidic products, which resulted from fragmentation of the carbon skeletons.
- Griesbaum, Karl,Kiesel, Gilbert,Mertens, Henri,Krieger-Beck, Petra,Henke, Henning
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p. 2198 - 2204
(2007/10/02)
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- A SIMPLE AND CONVENIENT SYNTHESIS OF β-HALOKETONES.
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A new rapid quantitative method to synthesize β-halo-ketones is described (eqn 2) wich utilizes the reaction of an enone with a tetraalkyl ammonium halide in anhydrous trifluoro acetic acid.The method is especially convenient for the preparation of β-iodoketones.
- Marx, John N.
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p. 1529 - 1532
(2007/10/02)
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