- Efficient preparation of vic-diacetates from epoxides and acetic anhydride in the presence of iron(III)-substituted polyoxometalate as catalyst
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Iron(III)-substituted polyoxometalate (TBA)4PFeW 11O39· 3H2O, has been demonstrated as an efficient catalyst in the ring opening of 1,2-epoxides with acetic anhydride for the one-pot synthesis of 1,2-diol esters in high to excellent yields under solvent-free condition. Copyright
- Yadollahi, Bahram,Esfahani, Farhad Kabiri
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- Heterogeneous acidic and eco-friendly reagents for mild and convenient conversion of epoxides to 1,2-diacetates
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A highly regioselective ring-opening of epoxides with acetic anhydride in the presence of hydrated disodium hydrogen phosphate and sodium hydrogen sulfate as efficient and eco-friendly reagents is described. The reactions are clean and lead to 1,2-diacetates in high to excellent yields.
- Gilanizadeh, Masumeh,Zeynizadeh, Behzad
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- Oxidation of Olefins with Benzenetelluric Anhydride
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Olefins were found to be oxidized by use of benzenetellurinic anhydride in acetic acid leading to vic-diacetates.Benzenetellurenic acid derivatives formed in situ are suggested as the active species.This diacetoxylation proceeds in net syn fashion probably via anti acetoxytellurenylation of the olefin followed by displacement of the phenyltelluro group by an acetoxy group with inversion.
- Kambe, Nobuaki,Tsukamoto, Takashi,Miyoshi, Noritaka,Murai, Shinji,Sonoda, Noboru
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- Diol-Ritter Reaction: Regio- And Stereoselective Synthesis of Protected Vicinal Aminoalcohols and Mechanistic Aspects of Diol Monoester Disproportionation
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The well-known epoxide-Ritter reaction generally affords oxazolines with poor to average regioselectivity. Herein, a mechanism-based study of the less known diol-Ritter reaction has provided a highly regioselective procedure for the synthesis of 1-vic-amido-2-esters from either terminal epoxides or 1,2-diols via Lewis acid-catalyzed monoesterification. When treated with a stoichiometric Lewis acid catalyst (BF3), these diol monoesters form dioxonium cation intermediates that are ring-opened with nitrile nucleophiles to form nitrilium intermediates, which undergo rapid and irreversible hydration to give the desired amidoesters. Diester byproduct formation is irreversible and appears to occur through disproportionation of diol monoester. With chiral epoxide starting materials, the formation of amidoester occurs with retention of configuration and no apparent erosion of optical purity as determined by single-crystal X-ray analyses and chiral chromatography, respectively. The direct access to chiral vic-amidoesters is especially practical with regard to the synthesis of antibacterial oxazolidinone analogues of the Zyvox antimicrobial family.
- Ondari, Mark E.,Klosin, Jerzy,Kruper, William R.,Lysenko, Ivan,Thomas, Pulikkottil J.,Cheng, Kevin,Abboud, Khalil A.,Kruper, William J.
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p. 2063 - 2074
(2021/10/20)
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- Vicinal Difunctionalization of Alkenes under Iodine(III) Catalysis involving Lewis Base Adducts
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The influence of a 2-pyridinyl substituent on the catalytic performance of aryl iodides as catalyst in iodine(III) chemistry was explored. An efficient Lewis base adduct between the pyridine nitrogen and the electrophilic iodine(III) center was identified and confirmed by X-ray analysis. This arrangement was shown to generate a kinetically competent superior catalyst structure for the catalytic dioxygenation of alkenes. It introduces the concept of Lewis base adduct formation as a kinetic factor in iodine(I/III) catalysis. (Figure presented.).
- Aertker, Kristina,Rama, Raquel J.,Opalach, Julita,Mu?iz, Kilian
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supporting information
p. 1290 - 1294
(2017/04/18)
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- A highly efficient protocol for regioselective ring-opening of epoxides with alcohols, water, acetic acid, and acetic anhydride catalyzed by SbF3
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SbF3as an efficient catalyst has been used for regioselective alcoholysis, acetolysis and hydrolysis of epoxides to the corresponding β-alkoxy, β-acetoxy alcohols, and 1,2-diols in high to excellent yields. This study also represents a convenient synthesis of vic-diacetates from ring-opening of epoxides with acetic anhydride.
- Zeynizadeh, Behzad,Gilanizadeh, Masumeh,Aminzadeh, Farkhondeh Mohammad
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p. 1051 - 1056
(2016/07/06)
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- A trans -1,2-cyclohexanediol diacetate method for the preparation of
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The invention discloses a preparation method of trans-1,2-cyclohexanol glycol diacetate. The preparation method comprises the following steps: (1) adding trans-1,2-cyclohexanol glycol and an esterification catalyst into a reaction container, then adding a reaction solvent, and heating to ensure that the trans-1,2-cyclohexanol glycol and the esterification catalyst are completely dissolved; (2) heating the reaction solution while stirring to boil the reaction solution, and when an organic phase overflow layered in a refluxing water separator returns to the reaction container, dropwise adding an esterifying agent into the reaction solution, and continuously reacting after dropwise adding the esterifying agent until the esterification reaction is finished; and (3) performing filtration, alkali cleaning, water washing and rectification on a reaction product to obtain the trans-1,2-cyclohexanol glycol diacetate. The preparation method disclosed by the invention is high in yield, low in investment and running costs and simple in production process, and is easy to realize industrial large-scale production.
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Paragraph 0035-0043
(2017/05/30)
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- Direct transformation of epoxides to 1,2-diacetates with Ac2O/B(OH)3 system
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Direct transformation of different kinds of epoxides to 1,2-diacetates was carried out easily and efficiently with Ac2O/B(OH)3 system. All reactions were carried out under reflux conditions within 2 h to afford 1,2-diacetates in high yields.
- Gilanizadeh, Masumeh,Zeynizadeh, Behzad
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p. 1234 - 1238
(2016/01/12)
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- A photoinduced cyclization cascade - Total synthesis of (-)-leuconoxine
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A protecting-group-free and enantioselective total synthesis of the monoterpenoid indole alkaloid (-)-leuconoxine was accomplished. The key step comprises a novel photoinduced domino macrocyclization/transannular cyclization involving the Witkop cyclization, for which additional mechanistic evidence is provided. This process furnishes a diaza[5.5.6.6]fenestrane skeleton, which is a hitherto unprecedented structure element.
- Pfaffenbach, Magnus,Gaich, Tanja
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supporting information
p. 6355 - 6357
(2015/04/22)
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- Prilezhaev dihydroxylation of olefins in a continuous flow process
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Epoxidation of both terminal and non-terminal olefins with peroxy acids is a well-established and powerful tool in a wide variety of chemical processes. In an additional step, the epoxide can be readily converted into the corresponding trans-diol. Batch-wise scale-up, however, is often troublesome because of the thermal instability and explosive character of the peroxy acids involved. This article describes the design and semi-automated optimization of a continuous flow process and subsequent scale-up to preparative production volumes in an intrinsically safe manner. Olefins go with the flow: Prilezhaev dihydroxylation can be performed on a large scale in continuous flow microreactor systems in the oxidation of terminal and internal olefins. Major drivers for a continuous flow process include better control, improved safety, and a faster overall process, leading to a significantly higher throughput. Copyright
- Van Den Broek, Bas A. M. W.,Becker, René,K?ssl, Florian,Delville, Mari?lle M. E.,Nieuwland, Pieter J.,Koch, Kaspar,Rutjes, Floris P. J. T.
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experimental part
p. 289 - 292
(2012/06/01)
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- Triflic acid catalyzed oxidative lactonization and diacetoxylation of alkenes using peroxyacids as oxidants
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A clean and efficient diacetoxylation reaction of alkenes catalyzed by triflic acid using commercially available peroxyacids as the oxidants has been developed. This method was also applied in oxidative lactonizations of unsaturated carboxylic acids in good to high yields.
- Kang, Yan-Biao,Gade, Lutz H.
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experimental part
p. 1610 - 1615
(2012/04/04)
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- Ligand-assisted rate acceleration in lanthanum
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The transesterification of an equimolar mixture of carboxylic esters and primary (1°), secondary (2°), and tertiary (3°) alcohols in hydrocarbon solvents was promoted with high efficiency by a lanthanum(III) complex, which was prepared in situ from lanthanum (III) isopropoxide (1 mol %) and 2-(2-methoxyethoxy)ethanol (2 mol %). The present La(III) catalyst was highly effective for the chemoselective transesterification in the presence of competitive 1°-and 2°-amines. Remarkably, esters were obtained in good to excellent yields as colorless materials without an inconvenient workup procedure.
- Hatano, Manabu,Furuya, Yoshiro,Shimmura, Takumi,Moriyama, Katsuhiko,Kamiya, Sho,Maki, Toshikatsu,Ishihara, Kazuaki
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supporting information; experimental part
p. 426 - 429
(2011/04/15)
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- One-pot catalytic conversion of epoxides to 1,2-diacetates with hydride transferring agents in acetic anhydride
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Direct transformation of structurally different epoxides to the corresponding 1,2-diacetates was studied with catalytic amounts of NaBH 4, LiAlH4, CaH2, and NaH. The reactions were carried out in refluxing acetic anhydride within 1.5-2.5h to give vic-diacetates in good to excellent yields. Conversion of R-(+)-styrene oxide to S-(+)-1,2-diacetoxy-1-phenylethane was carried out with good yield and stereospecificity with the NaBH4/Ac2O system at 0°C.
- Zeynizadeh, Behzad,Sadighnia, Leila
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scheme or table
p. 637 - 644
(2011/03/21)
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- Investigation of the catalytic activity of an electron-deficient vanadium(IV) tetraphenylporphyrin: A new, highly efficient and reusable catalyst for ring-opening of epoxides
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In this work, the catalytic activity of high-valent tetraphenylporphyrinatovanadium(IV) trifluoromethanesulfonate, [V IV(TPP)(OTf)2], in the nucleophilic ring-opening of epoxides is reported. This new V(IV) catalyst was used as an efficient catalyst for alcoholysis with primary (methanol, ethanol and n-propanol), secondary (iso-propanol) and tertiary alcohols (tert-butanol), hydrolysis and acetolysis of epoxides with acetic acid and also for the conversion of epoxides to 1,2-diacetates with acetic anhydride, conversion of epoxides to thiiranes with ammonium thiocyanate and thiourea, and for conversion of epoxides to acetonides with acetone. The catalyst was reused several times without loss of its activity.
- Taghavi, S. Abdolmanaf,Moghadam, Majid,Mohammadpoor-Baltork, Iraj,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza,Ahmadi, Venus
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experimental part
p. 2244 - 2252
(2011/10/03)
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- A green protocol for catalytic conversion of epoxides to 1,2-diacetoxy esters with phosphomolybdic acid alone or its supported on silica gel
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Catalytic conversion of structurally different epoxides to the corresponding 1,2-diacetoxy esters was carried out readily with phosphomolybdic acid alone or its supported on SiO2. The reactions were carried out under solvolytic or solvent free conditions within 5-15 min at room temperature. The product 1,2-diacetates were obtained in high to excellent yields. Supporting of phosphomolybdic acid on SiO2 showed the better catalytic activity than Al2O3. Conversion of optically pure R-(+)-styrene oxide to S-(+)-1,2-diacetoxy-1-phenylethane was carried with phosphomolybdic acid in high yield and stereospecificity.
- Zeynizadeh, Behzad,Sadighnia, Leila
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experimental part
p. 2644 - 2648
(2010/12/25)
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- A mild, rapid and highly regioselective ring-opening of epoxides and aziridines with acetic anhydride under solvent-free conditions using ammonium-12-molybdophosphate
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A highly regioselective ring opening of epoxides and aziridines can be carried out efficiently with acetic anhydride to form the acetates of the corresponding 1,2-diols and 2-amino-alcohols, respectively, using ammonium-12-molybdophosphate (AMP) as a heterogeneous catalyst, at room temperature, in the absence of solvent.
- Das, Biswanath,Reddy, V. Saidi,Tehseen, Fouzia
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p. 6865 - 6868
(2007/10/03)
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- Aerobic oxidation of alkenes to esters of vicinal diols with a syn-configuration catalyzed by I2 and the H5PV 2Mo10O40 polyoxometalate
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A new method for the synthesis of vicinal diols from alkenes has been developed. Reaction of molecular iodine in the presence of a polyoxometalate as oxidation catalyst under aerobic conditions in acetic acid solvent leads to the oxidative iodoacetoxylation of an alkene, i.e. formation of a 1,2-iodoacetate. Further in situ substitution of the iodide by water yields the 1,2-diol monoacetate with a predominantly (ca. 4.5:1) cis-configuration. Further esterification under the reaction's acidic conditions leads also to the cis-diacetate. The method may be valuable for the synthesis of cis-vicinal diols without use of toxic osmium catalysts. Georg Thieme Verlag Stuttgart.
- Branytska, Olena,Neumann, Ronny
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p. 2525 - 2527
(2007/10/03)
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- Tributylphosphine-catalyzed ring-opening reaction of epoxides and aziridines with acetic anhydride
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Reactions of aziridines and epoxides with acetic anhydride catalyzed by an organophosphine provided the corresponding esters of β-amino alcohols and 1,2-diols in high yields, respectively.
- Fan, Ren-Hua,Hou, Xue-Long
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p. 4411 - 4413
(2007/10/03)
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- Kinetic resolution of trans-2-acetoxycycloalkan-1-ols by lipase-catalysed enantiomerically selective acylation
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Kinetic resolution of a series of racemic trans-cycloalkane-1,2-diol monoacetates rac-2a-d was performed by enantiomerically selective transesterification with vinyl acetate catalysed by commercial and our own-prepared fungal lipases to yield diacetates (
- Bodai, Viktoria,Orovecz, Oliver,Szakacs, Gyoergy,Novak, Lajos,Poppe, Laszlo
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p. 2605 - 2612
(2007/10/03)
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- The Use of Bismuth(III) Acetate in 'Wet' and 'Dry' Prevost Reactions
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cis-Diol and trans-diol derivatives can be prepared from alkenes by reaction with iodine and bismuth(III) acetate in 'wet' and 'dry' acetic acid, respectively.Reactions using lesser amounts of bismuth(III) acetate under 'dry' conditions give iodo acetates and under 'wet' conditions a mixture of iodohydrins and iodo ethers.Comparison of these reactions with those promoted by silver, copper, mercury and thallium salts is included.
- Trainor, Robert W.,Deacon, Glen B.,Jackson, W. Roy,Giunta, Nunzio
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p. 1265 - 1280
(2007/10/02)
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- An Optimized Sequential Kinetic Resolution of trans-1,2-Cyclohexanediol
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Quantitative analysis of sequential kinetic resolutions (resolutions that proceed via two or more enantioselective steps) indicates that optimal reinforcement of the enantioselectivities occurs when the rates of the two steps are equal.Unter these conditions, the reinforcement is multiplicative and the overall enantioselectivity, ET(max), is given approximately by 1E2)>/2.To test these ideas we optimized the resolution of trans-1,2-cyclohexanediol, 1.The first step of the porcine liver esterase (PLE) catalyzed hydrolysis of trans-1,2-diacetoxycyclohexane proceeded 47 times faster than the second step and the resolution yielded 1 with only 58 percent ee at 44 molpercent.Addition of a hexane phase slowed the first step by selectively extracting the fast-reaction 1-diacetate (relative rate = 6) and increased the enantiomeric purity to 94 percent ee at 34 molpercent.The resolution of 1 was further improved using lipase from Pseudomonas cepacia (Amano P, PCL) which showed an ET(max) of >2000 as compared to an ET(max) for PLE of 54.Resolution with PCL after equalization of the rates of the two steps gave (R)-1 and recovered (S)-1-diacetate both with >99 percent ee.
- Caron, Gaetan,Kazlauskas, Romas J.
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p. 7251 - 7256
(2007/10/02)
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- Bismuth(III) Acetate: A Cheap, Efficient, and Environmentally Acceptable Reagent for 'Wet' and 'Dry' Prevost Reactions
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cis- and trans-Diol derivatives can be prepared from alkenes by reaction with bismuth(III) acetate in 'wet' and 'dry' acetic acid respectively.
- Campi, Eva M.,Deacon, Glen B.,Edwards, Gavin L.,Fitzroy, Mark D.,Giunta, Nunzio,et al.
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p. 407 - 408
(2007/10/02)
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- COORDINATION AND CATALYTIC REACTIONS OF UNSATURATED COMPOUNDS. VIII. HETEROGENEOUS CATALYTIC ACETOXYLATION OF 1-HEXENE AND CYCLOHEXENE
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During the acetoxylation of 1-hexene and cyclohexene in acetic acid in the presence of atmospheric oxygen and intermetallic compounds based on palladium and rhodium the ester groups are introduced into the substrate molecule.In the case of 1-hexene, the monoacetates of 1,2-hexanediol and 3-acetoxy-1-hexene are formed preferentially.The reactivity of the cyclic alkene is more clearly defined than that of the acyclic analog, and the catalyzate contains the cis- and trans-diacetoxy derivatives, 3-acetoxycyclohexene, and the products from ring concentration.The difference in the catalytic activity of the palladium and rhodium intermetallic compounds shows up mainly in the actoxylation of 1-hexene.The ring concentration products are evidently formed in the stages involving the transformation of the actoxonium ion.
- Devekki, A. V.,Yakushkin, M. I.,Egor'kov, A. N.,Belyaeva, N. V.,Mozzhukhina, T. N.,et al.
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p. 1680 - 1684
(2007/10/02)
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- THER RECATION OF α-METHYLSTYRENE ANALOGS AND RELATED COMPOUNDS WITH SODIUM PERBORATE IN ACETIC ACID
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A series of α-substituted styrene analogs have been reacted with sodium perborate in acetic acid to produce 1-acetoxy-2-aryl-2-popanol analogs in good yield.The reaction constitutes a mild and convenient method for the oxidation of styrene type double bon
- Gupton, John T.,Duranceau, Steven J.,Miller, John F.,Kosiba, Michael L.
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p. 937 - 948
(2007/10/02)
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- ALKENE OXIDATION BY AN IRON(II)/PERSULFATE/ACETIC ACID SYSTEM
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Mono- and disubstituted alkenes were converted to trans-vicinal diacetates by heating with an iron(II)/persulfate/acetic acid system.The synthetic utility and limitations were identified.A mechanism for the transformation is proposed wich involves an initial addition of sulfate radical anion to the alkene followed by solvolysis, addition, hydrolysis, and acetylation.
- Fristad, William E.,Peterson, John R.
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p. 1469 - 1476
(2007/10/02)
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- STUDIES ON THE SYNTHESIS OF HETEROCYCLIC COMPOUNDS. IX. SEPARATION OF DIASTEREOMERIC DIOL COMPOUNDS
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The separation of diastereomeric diols by transformation into the corresponding dioxastannolanes was carried out.The products are solid, stable and easily separable by fractional crystallization.By reaction of acids (or acyl halides) with the stannolanes the corresponding diols (or esters) were obtained in a high degree of purity.The structures of the compounds prepared were assigned on the basis of their analytical, physical and spectral data.
- Anchisi, Carlo,Maccioni, Antonio,Maccioni, Anna Maria,Podda, Gianni
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- IRON(II) CATALYZED ODIDATION OF ALKENES TO VICINAL DIACETATES
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Mono- and disubstituted alkenes are converted to trans-vicinal diacetates by heating with an acetic acid solution of ammonium persulfate and a ferrous sulfate catalyst.
- Fristad, William E.,Peterson, John R.
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p. 4547 - 4550
(2007/10/02)
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- Base-Catalyzed SO2-Induced Allylic Oxidation of Cyclohexene with Molecular Oxygen
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Sulfur dioxide has been found to promote a novel liquid-phase oxidation of cyclohexene with molecular oxygen in acetic acid as solvent.Oxidation at the allylic position occurs only if the reaction is base-catalyzed; with added acetoxy ions, e.g., the major product obtained is 2-cyclohexen-1-one together with minor amounts of 1,2-cyclohexanediol diacetate (mainly as the trans isomer), while a competitive autoxidation of sulfur dioxide to sulfur trioxide is observed.The results are discussed on the basis of an anion-radical mechanism involving the formation of sulfur dioxide stabilized peroxide ions.
- Tempesti, E.,Montoneri, E.,Giuffre, L.,Airoldi, G.
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p. 4278 - 4280
(2007/10/02)
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