- Synthesis of (9E)-isoambrettolide, a macrocyclic musk compound, using the effective lactonization promoted by symmetric benzoic anhydrides with basic catalysts
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Two alternative methods for the synthesis of (9E)-isoambrettolide are established via the rapid lactonization of the free threo-aleuritic acid or its protected seco-acid using substituted benzoic anhydrides with basic catalysts. The most efficient lactoni
- Shiina, Isamu,Hashizume, Minako
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- METHOD OF CYCLIC COMPOUNDS PRODUCTION IN OLEFINE METATHESIS REACTION AND USE OF RUTHENIUM CATALYSTS IN PRODUCTION OF CYCLIC OLEFINS IN OLEFINE METATHESIS REACTION
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The invention relates to a method for the preparation of cyclic compounds in the metathesis of olefins from acyclic dienes comprising terminal and/or non-terminal C=C double bonds; the invention also relates to the use of homogeneous ruthenium complexes and homogeneous ruthenium complexes deposited on a solid support as catalysts and/or pre-catalysts for the preparation of cyclic olefins in olefin metathesis reactions. Formula (I)
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Page/Page column 41; 42
(2018/11/22)
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- At Long Last: Olefin Metathesis Macrocyclization at High Concentration
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Macrocyclic lactones, ketones, and ethers can be obtained in the High-Concentration Ring-Closing Metathesis (HC-RCM) reaction in high yield and selectivity at concentrations 40 to 380 times higher than those typically used by organic chemists for similar macrocyclizations. The new method consists of using tailored ruthenium catalysts together with applying vacuum to distill off the macrocyclic product as it is formed by the metathetical backbiting of oligomers. Unlike classical RCM, no large quantities of organic solvents are used, but rather inexpensive nonvolatile diluents, such as natural or synthetic paraffin oils. Moreover, use of a protecting atmosphere or a glovebox is not needed, as the new catalysts are perfectly moisture and air stable. In addition, some other cyclic compounds previously reported as unobtainable by RCM in neat conditions, or in high dilutions even, can be formed with the help of the HC-RCM method.
- Sytniczuk, Adrian,Dabrowski, Micha?,Banach, ?ukasz,Urban, Mateusz,Czarnocka-?niada?a, Sylwia,Milewski, Mariusz,Kajetanowicz, Anna,Grela, Karol
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supporting information
p. 8895 - 8901
(2018/07/05)
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- Synthesis method of 16-hydroxy-9-ene-hexadeca-carboxylate
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The invention belongs to the field of pharmaceutical chemical engineering, and particularly relates to a synthesis method of 16-hydroxy-9-ene-hexadeca-carboxylate. The method comprises the following steps: 1) adding polyhydroxy fatty acid used as an initial raw material for reaction into a single-neck reaction flask, adding silicone oil and raw acid carboxylate, and controlling the synthesis reaction temperature at 50-120 DEG C and the reaction time at 2-8 hours in a nitrogen protective atmosphere; 2) further adding an olefination reaction catalyst, and controlling the olefination reaction temperature at 110-180 DEG C and reaction time at 3-8 hours; and 3) cooling to room temperature, adding a right amount of H2O, performing stirring hydrolysis for about 30 minutes, then regulating the pH value to 5.0, extracting with ethyl acetate, drying with anhydrous sodium sulfate, and performing rotary evaporation to obtain the crude product 16-hydroxy-9-ene-hexadeca-carboxylate. The method is simple to operate, reagents involved in the reaction are environment-friendly, and the target product is simple to separate and purify.
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Paragraph 0035; 0036; 0046
(2017/08/28)
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- METHOD FOR PRODUCING OMEGA-HYDROXY FATTY ACID ESTER AND PRECURSOR COMPOUND THEREOF
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Provided is a method for producing a compound represented by Formula (III) while the production of by-products due to, for example, dimerization of a raw material or isomerization of a double bond position is suppressed. The method is a method for producing omega-hydroxy fatty acid ester and a precursor compound thereof of Formula (III), in which an alcohol derivative and a carboxylic acid derivative are subjected to a metathesis reaction in the presence of a catalyst to obtain a compound of Formula (III), wherein the alcohol derivative is at least one selected from the group consisting of a compound of Formula (VI) and a compound of Formula (I), and the carboxylic acid derivative is at least one selected from the group consisting of a compound of Formula (VII) and a compound of Formula (II), wherein the case where the alcohol derivative is formed of a compound of Formula (I) and the carboxylic acid derivative is formed of a compound of Formula (II) is excluded,
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Paragraph 0124
(2016/07/27)
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- Preparation and some reactions of ω-chloro derivatives from aleuritic acid and related compounds
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Synthesis of ω-chloro compounds obtained from aleuritic acid and its derivatives have been carried out and the known triphenylphosphine-carbon tetrachloride procedure has been found to be the most suitable for this purpose. The C-Cl bond has been found to be sufficiently reactive towards a Wittig reaction, dilithium tetrachlorocuprate catalyzed alkylation and macrocyclization, indicating the usefulness of the chloro compounds.
- Subramanian,Passey, Sarita
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- A Simple Synthesis of trans-Δ9-Isoambrettolide, Dihydroambrettolide, and Methyl 16-Acetoxy-9-hexadecenoate
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Δ9-Isoambrettolide (2) and methyl 16-acetoxy-9-hexadecenoate (3) are prepared from aleuritic acid and dimethylformamide dialkyl acetals by a one-pot reaction.Catalytic hydrogenation of products 2 and 3 affords dihydroambrettolide (6) and methyl 16-acetoxyhexadecanoate (7), respectively.
- Villemin, Didier
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p. 154 - 155
(2007/10/02)
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- Cyanuric chloride, a useful reagent for macrocyclic lactonization
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Six ω-hydroxy acids have been converted to macrocyclic lactones by treatment with cyanuric chloride and triethylamine in acetone at room temperature. The mechanism apparently involves activation of both the carboxyl and hydroxyl groups.
- Venkataraman,Wagle
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p. 1893 - 1896
(2007/10/02)
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