- Syntheses of rac- and optically active 2-alkyl-γ-butyrolactones and 2- alkyl-cyclobutanones
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γ-Butyrolactones have been produced in good yield from alkylidene cyclopropanes, as racemates or as an enantiomerically enriched mixture of stereoisomers (e.e.>60%) depending upon the method used. Optically active cyclobutanones which are intermediate in the process have been in some cases isolated. We show the limitations of a competitive method previously described and point out its weak step.
- Krief, Alain,Ronvaux, Alain,Tuch, Arounarith
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- Silver triflate-catalysed synthesis of γ-lactones from fatty acids
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A silver(i)-based catalytic system was found to efficiently promote the double-bond isomerization of unsaturated fatty acids and at the same time to mediate the intramolecular addition of the carboxylate group to the isomerized double bond under selective formation of five-ring lactones. The resulting one-step isomerization-γ-lactonization process allows the direct conversion of unsaturated fatty acids into the corresponding γ-lactones in good yields.
- Goossen, Lukas J.,Ohlmann, Dominik M.,Dierker, Markus
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- Tandem isomerization-lactonization of olefinic fatty acids using the Lewis acidic ionic liquid, choline chloride·2ZnCl2
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The tandem isomerization-lactonization of unsaturated fatty acids to their corresponding γ-lactones was carried out for the first time in the presence of a Lewis acidic ionic liquid, choline chloride·2ZnCl 2. The ionic liquid initially catalyzes the stepwise migration of the double bond along the carbon chain toward the carboxyl group at the Δ4 position, which subsequently undergoes lactonization resulting in the formation of γ-lactones. This one step process allows the formation of γ-lactone in good yield with little or no formation of δ-lactones. The studied ionic liquid plays the dual role of solvent as well as catalyst.
- Akula, Shivaraju,Kumar, Pandari Phani,Prasad, Rachapudi B.N.,Kanjilal, Sanjit
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- Highly active, immobilized ruthenium catalysts for oxidation of alcohols to aldehydes and ketones. Preparation and use in both batch and flow systems
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A novel, highly active immobilized ruthenium catalyst, which can be successfully used in oxidation of alcohols to aldehydes and ketones, has been developed. In contrast to most immobilized catalysts, the Ru catalyst has activity that is higher than that of the original nonimmobilized catalyst. In a batch system, the Ru catalyst was recovered and reused several times without loss of activity. The catalyst was also applied to a flow system, In which excellent conversions and yields were demonstrated. No leaching of Ru was observed in both cases.
- Kobayashi, Shu,Miyamura, Hiroyuki,Akiyama, Ryo,Ishida, Tasuku
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- Production method of synthesizing gamma-undecalactone synthetic perfume by reactive distillation
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The invention belongs to the technical field of fine chemical production, and specifically relates to a production method of synthesizing gamma-undecalactone synthetic perfume by reactive distillation. The method includes the following steps: (a) mixing raw materials to obtain a mixture of ingredients; (b) discharging materials from an octanol elevated tank into a preheater for preheating; (c) pumping octanol into a high-boiling-point feed section of a reaction zone of a reactive distillation column, and pumping the mixture of ingredients into a low-boiling-point feed section of the reaction zone of the reactive distillation column; (d) separating out a crude product of gamma-undecalactone from the bottom of the reactive distillation column; (e) transferring the octanol separated in the step (d) to the preheater through a material pump to continue to participate in the reaction; and (f) further separating and purifying the crude product of gamma-undecalactone separated in the step (d).According to the production method provided by the present invention, a reactive distillation technology is adopted to timely separate by-product water, tert-butanol and low-boiling-point impuritiesproduced by a side reaction from the reaction system, so as to shorten the reaction time, improve the reaction speed and enhance the reaction efficiency.
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Paragraph 0046-0070
(2019/01/08)
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- A reaction synthesis and rectification γ - XI lactone with synthetic perfume method (by machine translation)
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The invention belongs to the technical field of fine chemicals, in particular to a kind of reaction synthesis and rectification γ - XI lactone with synthetic perfume method, comprises the following steps: (a) the octanol, acrylic acid and b - tert butyl peroxide mixture are mixed to obtain a mixture; (b) weighing and [...], added to the reaction of the rectification column and in the heater, the step (a) the ingredients in the mixture into the reaction zone to the reaction of the rectification column; (c) the opening reaction of the rectification column and condensed water, separated from the bottom of the crude γ - undecalactone; (d) will be γ - undecalactone transferred into the rotary evaporator in the crude product, the vacuum, temperature and rotation speed, collecting γ - undecalactone; this invention adopts the reaction distillation technique, the by-product from the reaction system in a timely manner to separate, to reaction promoting separation, in order to separate two-way to promote reaction, enhance the efficiency of the reaction, to ensure that the reaction yield. (by machine translation)
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Paragraph 0040-0056
(2019/01/08)
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- Efficient synthesis of γ-lactones via gold-catalyzed tandem cycloisomerization/oxidation
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A novel Au-catalyzed tandem cycloisomerization/oxidation of homopropargyl alcohols was developed. Various γ-lactones can be accessed readily by utilizing this strategy. Notably, the mechanism of this reaction is distinctively different from the related Ru-catalyzed reactions where the ruthenium vinylidene intermediate was proposed.
- Shu, Chao,Liu, Meng-Qi,Sun, Yu-Zhe,Ye, Long-Wu
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p. 4958 - 4961,4
(2012/12/12)
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- Efficient synthesis of γ-lactones via gold-catalyzed tandem cycloisomerization/oxidation
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A novel Au-catalyzed tandem cycloisomerization/oxidation of homopropargyl alcohols was developed. Various γ-lactones can be accessed readily by utilizing this strategy. Notably, the mechanism of this reaction is distinctively different from the related Ru-catalyzed reactions where the ruthenium vinylidene intermediate was proposed.
- Shu, Chao,Liu, Meng-Qi,Sun, Yu-Zhe,Ye, Long-Wu
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p. 4958 - 4961
(2013/01/15)
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- A novel synthesis of γ,δ-unsaturated aldehydes from α-formyl-γ-lactones
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A preparatively useful one-step transformation of γ,γ- disubstituted α-formyl-γ-lactones into trisubstituted γ,δ-unsaturated aldehydes is described, by means of catalytic amounts of either AcOH or AcOEt in the vapor phase over a glass support. A mechanistic rationale is proposed. Copyright
- Snowden, Roger L.,Brauchli, Robert,Linder, Simon
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experimental part
p. 1216 - 1225
(2011/09/16)
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- Process for the production of lactones
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The invention is directed to a process for the lactonization of carboxylic acids, wherein unsaturated carboxylic acids and/or 4-hydroxylsubstituted carboxylic acids with at least 7 carbon atoms are reacted in the presence of a fluorinated alkane sulfonic acid or salts thereof, preferably in the presence of a trifluoromethanesulfonic acid or salts thereof.
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Page/Page column 8
(2010/11/03)
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- An efficient oxidative lactonization of 1,4-diols catalyzed by Cp*Ru(PN) complexes
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An efficient oxidative lactonization of 1,4-diols in acetone is accomplished by the well-defined ruthenium catalyst, whose bifunctional nature underlies the high efficiency as well as unique chemo- and regioselectivity of the reaction which provides a rapid access to γ-butyrolactones including flavor lactones hinokinin, and muricatacin.
- Ito, Masato,Osaku, Akihide,Shiibashi, Akira,Ikariya, Takao
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p. 1821 - 1824
(2008/02/02)
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- Preparation of titanated alkoxyallenes from 3-alkoxy-2-propyn-1-yl carbonates and (η2-propene)Ti(O-i-Pr)2 as an efficient ester homoaldol equivalent
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(equation presented) 3-Alkoxy-2-propyn-1-yl carbonates (2) react with a divalent titanium reagent (η2-propene)Ti(O-i-Pr)2 to afford titanated alkoxyallenes 1 which, in turn, react with aldehydes regiospecifically to provide the corresponding γ-addition products in good to excellent yields, thus affording a convenient method for synthesizing γ-hydroxy esters 3 and/or γ-butyrolactones 4.
- Hanazawa, Takeshi,Okamoto, Sentaro,Sato, Fumie
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p. 2369 - 2371
(2007/10/03)
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- A new coupling reaction between β-lactones and electrophiles mediated by a SmI2/(NiI2 catalytic) system
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β-lactones react with ketones aldehydes and imines in the presence of a SmI2/(NiI2 catalytic) system to afford substituted tetrahydrofuranones and pyrrolidinones.
- Machrouhi, Fouzia,Namy, Jean-Louis
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p. 11111 - 11122
(2007/10/03)
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- Oxidation of Diols with Sodium Bromite Trihydrate in Organic Solvents in the Presence of Alumina
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The title oxidation of diols with two primary hydroxy groups (symmetrical diols) and those with both a primary and a secondary hydroxy group (unsymmetrical diols) gives the corresponding lactones or the hydroxy ketones, being dependent upon the types of diols.
- Morimoto, Takashi,Hirano, Masao,Iwasaki, Keiko,Ishikawa, Takashi
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- A general synthesis of (+)-γ-substituted γ-butyrolactones using a kinetic alkylation-ozonolysis procedure
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A synthesis of (±)-γ-substituted γ-butyrolactones is described in which the key intermediates, γ-ketoesters, are prepared from the readily available 6-methyl-5-hepten-2-one using a kinetic alkylation-ozonolysis procedure; the method allows terminal ester and Z-alkene groups to be incorporated into the side-chain and thus can be used for the synthesis of (+)-γ-jasmolactone as well as other naturally occurring lactones.
- Gavin,Geraghty
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p. 1351 - 1361
(2007/10/02)
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- New one carbon homologation reagents utilizing electrochemical oxidation of organosilicon compounds
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Phenylthio(trimethylsilyl)methane, phenylthiobis(trimethylsilyl)methane, methoxy(trimethylsilyl)-methane, and methoxybis(trimethylsilyl)methane are deprotonated and the resulting anions are alkylated with electrophiles such as organic halides. The alkylation products are readily converted into the corresponding dimethyl acetals or methyl esters by electrochemical oxidation in methanol.
- Yoshida,Matsunaga,Murata,Isoe
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p. 615 - 624
(2007/10/02)
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- METHOXY(TRIMETHYLSILYL)METHANE AND METHOXYBIS(TRIMETHYLSILYL)METHANE AS NEW REAGENTS FOR HOMOLOGATION
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New synthons of formyl anion methoxy(trimethylsilyl)methane (1)) and alkoxycarbonyl anion (methoxybis(trimethylsilyl)methane (2)) have been developed using oxidative cleavage of the carbon-silicon bond by anodic oxidation.
- Yoshida, Jun-ichi,Matsunaga, Shin-ichiro,Isoe, Sachihiko
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p. 219 - 222
(2007/10/02)
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- THE REACTION OF ALKYL 4-HYDROXY-2-ALKYNOATES AND 4-HYDROXY-2-ALKYN-1-ONES WITH PALLADIUM TRIBUTYLAMMONIUM FORMATE AND WITH TRIBUTYLAMINE: PREPARATION OF 1,4-DICARBONYL COMPOUNDS
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Ethyl 4-oxo-2-alkenoates and 1,4-dioxo-2-alkenes are easily prepared by treating ethyl 4-hydroxy-2-alkynoates and 4-hydroxy-2-alkyn-1-ones with n-tributylamine.Treatment of ethyl 4-hydroxy-2-alkynoates and 4-hydroxy-2-alkyn-1-ones with palladium-tributylammonium formate produces ethyl 4-oxo-alkanoates and 1,4-alkandiones in good to high yield through a novel one-pot isomerization/hydrogenation reaction.
- Arcadi, A.,Cacchi, S.,Marinelli, F.,Misiti, D.
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p. 1457 - 1460
(2007/10/02)
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- THE PALLADIUM -TRIBUTYL FORMATE REAGENT IN THE STEREOSELECTIVE HYDROGENATION, AND STEREO- AND REGIOSELECTIVE HYDROARYLATION OF ALKYL 4-HYDROXY-2-ALKYNOATES: A ROUTE TO SUBSTITUTED BUTENOLIDES
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The reaction of aryl iodides with alkyl 4-hydroxy-2-alkynoates in the presence of formic acid, tri-n-butylamine and a palladium(II) catalyst provides a convenient route to functionalized substituted butenolides through a one pot hydroarylation/cyclization reaction.In the presence of formic acid, tri-n-butylamine and a palladium(II) catalyst, alkyl 4-hydroxy-2-alkynoates undergo a one pot hydrogenation/cyclization reaction to the butenolide ring.By increasing the excess of formic acid, direct formation of saturated γ-lactones can be observed.Reaction occur with high stereoselectivity and, in the case of the hydroarylation, with goog regioselectivity.
- Arcadi, A.,Bernocchi, E.,Burini, A.,Cacchi, S.,Marinelli, F.,Pietroni, B.
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p. 481 - 490
(2007/10/02)
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- Free Radical Addition of 2-Bromoalkanoic Acids to Alkenes
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The benzoyl peroxide-catalyzed reaction of 2-bromoalkanoic acids such as bromoacetic, 2-bromopropionic, and 2-bromobutyric acid with 1-alkenes was found to proceed thorough the addition of the C-Br bond across the double bond followed by cyclization affording 4-alkanolides in good yields.
- Nakano, Taichi,Kayama, Mikio,Nagai, Yoichiro
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p. 1049 - 1052
(2007/10/02)
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- SOME (E)-1,4-ALKADIENE DERIVATIVES AND THE SYNTHESIS OF 5-(3E,6-HEPTADIENYL)DIHYDRO-2(3H)-FURANONE
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From 2-allyl-3-chlorotetrahydropyran, (E)-4,7-octadien-1-ol and (E)-4,7-octadienal were obtained.The aldehyde was conjugated with ethyl acrylate to give a γ-keto ester from which 5-(3E,6-heptadienyl)dihydro-2(3H)-furanone was prepared. 4-Oxo- and 4-hydroxy-derivatives of decanoic and undecanoic acids are discussed.
- Voaden, Denys J.
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- Electroorganic Chemistry. Part 73. Electroreductive Cross-coupling of 3-Substituted Alkanoic Acid Esters with Aldehydes or Acid Anhydrides
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Elecroreductive cross-coupling reaction of 3-phenylthioalkanoic acids esters (4a) or quaternary ammonium salts of 3-aminoalkanoic acid esters (4b) with aldehydes gave the corresponding γ-lactones in one step.The cross-coupling reaction of (4b) with acid anhydrides leading to the formation of the corresponding γ-keto esters is also described.
- Shono, Tatsuya,Matsumura, Yoshihiro,Kashimura, Shigenori
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p. 1922 - 1935
(2007/10/02)
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- FREE RADICAL ADDITION OF α-BROMOCARBOXYLIC ACIDS TO OLEFINS LEADING TO γ-BUTYROLACTONES
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Benzoyl peroxide-catalyzed free radical addition of bromoacetic, α-bromopropionic, and α-bromobutyric acids to olefins took place under mild conditions to afford γ-alkyl-, γ-alkyl-α-methyl-, and γ-alkyl-α-ethyl-γ-butyrolactones in good yields.
- Nakano, Taichi,Kayama, Mikio,Matsumoto, Hideyuki,Nagai, Yoichiro
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p. 415 - 418
(2007/10/02)
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- Electroreductive hydrocoupling of activated olefins with ketones or aldehydes in the presence of trimethylchlorosilane
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Electroreductive crossed hydrocoupling of α,β-unsaturated esters with aldehydes or ketones in the presence of trimethylchlorosilane afforded γ-lactones in good yields. Similarly, α,β-unsaturated nitriles gave γ-hydroxynitriles in high yields.
- Shono, Tatsuya,Ohmizu, Hiroshi,Kawakami, Souta,Sugiyama, Hiroshi
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p. 5029 - 5032
(2007/10/02)
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- Carbon-Carbon Bond Formation by the Use of Chloroiodomethane as a C1 Unit. II. The Preparation and Synthetic Application of 1-Chloro-3-iodoheptane
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Terminal alkenes, R-CH=CH2 (R=Et, n-Pr, n-Bu, N-Hex), were readily transformed into 1-chloro-3-iodoalkanes by the AIBN-induced free radical addition of chloroiodomethane.Thus, 1-chloro-3-iodoheptane was obtained from 1-hexene in an 88percent yield; this in turn was allowed to react with dialkyl malonates in the presence of alkoxides in alcohols to give dialkyl 2-butylcyclobutane-1,1-dicarboxylates and dialkyl (E)-3-octene-1,1-dicarboxylates (7), either of which could be obtained preferentially by the choice of the experimental parameters.The olefinic product, 7, was further utilized for the synthesis of (E)-5-decenyl acetate and/or 1,4-nonanolide.
- Miyano, Sotaro,Hokari, Hiroshi,Umeda, Yoshiharu,Hashimoto, Harukichi
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p. 770 - 774
(2007/10/02)
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