- Dihydroxylation of olefins catalyzed by zeolite-confined osmium(0) nanoclusters: An efficient and reusable method for the preparation of 1,2-cis-diols
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Addressed herein is a novel, eco-friendly, recoverable, reusable and bottleable catalytic system developed for the dihydroxylation of various olefins yielding 1,2-cis-diols. In our protocol, zeolite-confined osmium(0) nanoclusters (zeolite-Os0) are used as reusable catalyst and H 2O2 served as a co-oxidant. Zeolite-Os0 are found to be highly efficient and selective catalysts for the dihydroxylation of a wide range olefins in an aqueous acetone mixture at room temperature. In all of the olefins surveyed, the catalytic dihydroxylation reaction proceeds smoothly and the corresponding 1,2-cis-diols are obtained in excellent chemical yield under the optimized conditions. The present heterogeneous catalyst system provides many advantages, such as being eco-friendly and industrially applicable over the traditional homogenous OsO4-NMO system for the dihydroxylation of olefins.
- Metin, Oender,Alp, Nurdan Alcan,Akbayrak, Serdar,Bier, Abdullah,Gueltekin, Mehmet Serdar,Oezkar, Saim,Bozkaya, Uur
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experimental part
p. 1488 - 1492
(2012/06/29)
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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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- A multicatalyst system for the one-pot desymmetrization/oxidation of meso-1,2-alkane diols
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Two is better than one: We demonstrate the viability of an organocatalytic reaction sequence along a short peptide backbone that carries two independent catalytic functionalities, which allow the rapid, one-pot acylative desymmetrization and oxidation of meso-alkane-1,2-diols to the corresponding acetylated acetoins with good yields and enantioselectivities (see scheme). Copyright
- Mueller, Christian E.,Hrdina, Radim,Wende, Raffael C.,Schreiner, Peter R.
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supporting information; experimental part
p. 6309 - 6314
(2011/08/07)
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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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- Adrenaline profiling of lipases and esterases with 1,2-diol and carbohydrate acetates
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The adrenaline test for enzymes is a general back-titration procedure to detect 1,2-diols, 1,2-aminoalcohols and α-hydroxyketones reaction products of enzyme catalysis by colorimetry. The method was used to profile a series of esterases and lipases for their esterolytic activity on a series of carbohydrate and polyol acetates. Substrates were prepared by peracetylation and used for parallel microtiter-plate analysis of enzyme activities. This method can be used to achieve a rapid and automated characterization of a set of enzymes during HTS screening.
- Wahler, Denis,Boujard, Olivier,Lefèvre, Fabrice,Reymond, Jean-Louis
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p. 703 - 710
(2007/10/03)
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- A one-step procedure for the monoacylation of symmetrical 1,2-diols
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A series of lanthanide (III) salts have been shown to catalyze the monoacylation of symmetrical 1,2-diols by carboxylic acid anhydrides with surprisingly high selectivity.
- Clarke, Paul A.,Kayaleh, Nadim E.,Smith, Martin A.,Baker, James R.,Bird, Stephan J.,Chan, Chuen
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p. 5226 - 5231
(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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- Rhodium(I)- and iridium(I)-catalyzed hydroboration reactions: Scope and synthetic applications
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A study of the rhodium(I)- and iridium(I)-catalyzed hydroboration of olefins with catecholborane is described. Applications to organic synthesis were one focus of this investigation. The scope of the reaction was defined, and issues of stereoselection were addressed. The rhodium-catalyzed hydroboration of several classes of allylic alcohols was found to be highly diastereoselective, preferentially affording the isomer complementary to that furnished by the uncatalyzed variant of the reaction (9-BBN). The first two general approaches to effecting a directed olefin hydroboration were developed. Both phosphinites and amides proved capable of delivering the transition metal reagent.
- Evans, David A.,Fu, Gregory C.,Hoveyda, Amir H.
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p. 6671 - 6679
(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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- 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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p. 269 - 272
(2007/10/02)
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- DOMINANT cis-DIACETOXYLATION OF ALKENES WITH TELLURIUM(IV) OXIDE AND LITHIUM BROMIDE IN ACETIC ACID
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Oxidation of alkenes with tellurium(IV) oxide and lithium bromide in acetic acid affords the corresponding α,β-diacetoxyalkanes in good yields after acetylation of the primary products with acetic anhydride/pyridine.From cyclic alkenes such as cyclopentene, cyclohexene, cycloheptene, and 1,4-cyclohexadiene, the cis-diacetate is obtained as almost the sole product.In the cases of linear cis alkenes such as cis-2-octene and cis-4-octene cis-stereochemistry is also preferred (cis/trans = 87-89/13-11), while the proportion of the cis-product is decreased in the cases of the corresponding trans-alkenes (cis/trans = 56-58/44-42).Transformation of a C-Te bond to a C-OAc bond under these reaction conditions is shown unambiguously by using β-chloroalkyltellurium(IV) trichlorides (TeCl4 adducts of alkenes) and β-oxyalkyl phenyl tellurides (oxytellurenylation products of alkenes), cis-diacetates being solely formed from the trans-tellurium compounds in a cyclohexyl system.One of the possible reaction patways for the oxidation is proposed which involves the acetoxy-, hydroxy-, and/or halogeno-tellurinylation of a double bond followed by an SN2 type acetolysis of the produced C-Te bond.
- Uemura, Sakae,Ohe, Kouichi,Fukuzawa, Shin-Ichi,Patil, Suresh R.,Sugita, Nobuyuki
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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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- 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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