- Preparation method of vinylethylene sulfite
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The invention belongs to the field of additives, and particularly relates to a preparation method of vinylethylene sulfite. The invention discloses a preparation method of vinylethylene sulfite, whichcomprises the following step: reacting 3-butylene-1,2-diol with thionyl chloride to obtain vinylethylene sulfite. The preparation method has the advantages of simple operation, easily available raw materials, greenness, environmental protection, and great implementation value and social and economic benefits.
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Paragraph 0033-0034
(2021/03/31)
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- Iridium-Catalyzed Enantioselective Allylic Substitutions of Racemic, Branched Trichloroacetimidates with Heteroatom Nucleophiles: Formation of Allylic C?O, C?N, and C?S Bonds
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A broadly applicable methodology for the regio- and enantioselective construction of branched allylic carbon-heteroatom bonds from racemic, secondary allylic trichloroacetimidates has been developed. The branched allylic substrates undergo dynamic kinetic asymmetric substitution reactions with a number of unactivated anilines and carboxylic acids as well as unactivated aromatic thiols in the presence of a chiral bicyclo[3.3.0]octadiene-ligated iridium catalyst. The allylic C?O, C?N, and C?S bond containing products are obtained in synthetically useful yield and selectivity. Mechanistic studies suggest that the iridium-catalyzed enantioselective substitution reactions of heteroatom nucleophiles with allylic trichloroacetimidate substrates through an outer-sphere nucleophilic addition mechanism. In addition, the chiral diene-ligated iridium catalyst is effective at promoting asymmetric aminations of acyclic secondary anilines. Importantly, this catalytic iridium methodology enables the use of alkyl substituted allylic electrophiles. (Figure presented.).
- Arachchi, Madhawee K.,Nguyen, Hien M.
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supporting information
p. 4239 - 4246
(2021/07/16)
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- An Amphiphilic (salen)Co Complex – Utilizing Hydrophobic Interactions to Enhance the Efficiency of a Cooperative Catalyst
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An amphiphilic (salen)Co(III) complex is presented that accelerates the hydrolytic kinetic resolution (HKR) of epoxides almost 10 times faster than catalysts from commercially available sources. This was achieved by introducing hydrophobic chains that increase the rate of reaction in one of two ways – by enhancing cooperativity under homogeneous conditions, and increasing the interfacial area under biphasic reaction conditions. While numerous strategies have been employed to increase the efficiency of cooperative catalysts, the utilization of hydrophobic interactions is scarce. With the recent upsurge in green chemistry methods that conduct reactions ‘on water’ and at the oil-water interface, the introduction of hydrophobic interactions has potential to become a general strategy for enhancing the catalytic efficiency of cooperative catalytic systems. (Figure presented.).
- Solís-Mu?ana, Pablo,Salam, Joanne,Ren, Chloe Z.-J.,Carr, Bronte,Whitten, Andrew E.,Warr, Gregory G.,Chen, Jack L.-Y.
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supporting information
p. 3207 - 3213
(2021/06/01)
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- Palladium-catalyzed stereoselective (3 + 2) cycloaddition of vinylethylene carbonates with cyclicN-sulfonyl ketimines
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A diastereoselective (3 + 2) cycloaddition ofN-sulfonyl ketimines with vinylethylene carbonates (VECs) in the presence of Pd2dba3·CHCl3and PPh3has been developed. The reaction of various substituted VECs and diverse cyclicN-sulfonyl ketimines proceeded smoothly under mild conditions, giving highly functionalized oxazolidine frameworks in good to excellent yields with moderate to good diastereoselectivities. With the use of spiroketal-based diphosphine SKP as a chiral ligand, an asymmetric version of the current (3 + 2) cycloaddition was achieved, and chiral products were obtained in >99% ee in most cases.
- Gao, Xing,Zhu, Dongyu,Jiang, Feng,Liao, Jianning,Wang, Wei,Wu, Yongjun,Zheng, Lufei,Guo, Hongchao
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supporting information
p. 4877 - 4881
(2021/06/16)
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- Olefin reaction in the catalyst and the olefin production
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PROBLEM TO BE SOLVED: To provide a catalyst for obtaining an olefin in high selectivity with a vicinal diol as a raw material.SOLUTION: A catalyst for olefination reaction for use in a reaction to produce an olefin by a reaction of a polyol, having two adjacent carbon atoms each having a hydroxy group, with hydrogen comprises: a carrier; at least one oxide selected from the group consisting of oxides of the group 6 elements and oxides of the group 7 elements supported on the carrier; and at least one metal selected from the group consisting of silver, iridium, and gold supported on the carrier.SELECTED DRAWING: None
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Paragraph 0145-0146; 0149
(2020/10/31)
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- Asymmetric Synthesis of N-Fused 1,3-Oxazolidines via Pd-Catalyzed Decarboxylative (3+2) Cycloaddition
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Efficient synthesis of optically active N-fused 1,3-oxazolidines containing quaternary and tertiary stereocenters was achieved via Pd-catalyzed asymmetric (3+2) cycloadditions of sulfamate-derived cyclic imines and vinylethylene carbonates. Using a chiral phosphoramidite ligand, the cycloadditions proceeded effectively providing sulfamidate-fused 1,3-oxazolidines in high yields (up to 96%) with stereoselectivities (up to 25:1 dr; >99% ee). Additionally, the scale-up reaction and further transformations of the product were also achieved demonstrating the synthetic utility toward the construction of useful heterocycles such as chiral oxazoline bearing a quaternary stereocenter. (Figure presented.).
- Ahn, Hye-In,Cho, Ho-Jun,Kim, Ju Hyun,Park, Jong-Un,Xuan, Zi
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supporting information
(2020/04/22)
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- Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
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The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadienes, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) carbene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones to afford alcohol-, amine-, or aniline-containing 1,3-dienes in moderate to high yields and with excellent stereoselectivity. This protocol features operational simplicity, mild reaction conditions, a broad substrate scope, and gram-scalability. Notably, a structurally unique allylic Pd(II) intermediate was isolated and characterized. DFT calculation and control experiments demonstrated that a rare Pd(0) carbene intermediate could be involved in this reaction. Moreover, the polysubstituted butadienes as novel building blocks were unprecedentedly assembled into macrocycles, which efficiently inhibited the P-glycoprotein and dramatically reversed multidrug resistance in cancer cells by 190-fold.
- Chen, Xiangyang,Hao, Jiping,Houk, K. N.,Li, Yingzi,Lou, Liguang,Quan, Haitian,Song, Bichao,Wang, Lu,Xia, Yuanzhi,Xie, Peipei,Xu, Zhongliang,Yang, Weibo
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supporting information
p. 9982 - 9992
(2020/06/27)
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- Transfer hydrogenation of cyclic carbonates and polycarbonate to methanol and diols by iron pincer catalysts
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Herein, we report the first example on the use of an earth-abundant metal complex as the catalyst for the transfer hydrogenation of cyclic carbonates to methanol and diols. The advantage of this method is the use of isopropanol as the hydrogen source, thus avoiding the handling of flammable hydrogen under high pressure. The reaction offers an indirect route for the reduction of CO2 to methanol. In addition, poly(propylene carbonate) was converted to methanol and propylene glycol. This methodology can be considered as an attractive opportunity for the chemical recycling of polycarbonates.
- Liu, Xin,De Vries, Johannes G.,Werner, Thomas
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p. 5248 - 5255
(2019/10/11)
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- The Role of Trichloroacetimidate to Enable Iridium-Catalyzed Regio- And Enantioselective Allylic Fluorination: A Combined Experimental and Computational Study
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Asymmetric allylic fluorination has proven to be a robust and efficient methodology with potential applications for the development of pharmaceuticals and practical synthesis for 18F-radiolabeling. A combined computational (dispersion-corrected
- Sorlin, Alexandre M.,Mixdorf, Jason C.,Rotella, Madeline E.,Martin, Robert T.,Gutierrez, Osvaldo,Nguyen, Hien M.
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supporting information
p. 14843 - 14852
(2019/10/11)
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- Functionalizable Stereocontrolled Cyclopolyethers by Ring-Closing Metathesis as Natural Polymer Mimics
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Whereas complex stereoregular cyclic architectures are commonplace in biomacromolecules, they remain rare in synthetic polymer chemistry, thus limiting the potential to develop synthetic mimics or advanced materials for biomedical applications. Herein we
- Alkattan, Mohammed,Prunet, Jo?lle,Shaver, Michael P.
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supporting information
p. 12835 - 12839
(2018/09/25)
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- A versatile biobased continuous flow strategy for the production of 3-butene-1,2-diol and vinyl ethylene carbonate from erythritol
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A versatile, tunable and robust continuous flow procedure for the deoxydehydration (DODH) of biobased erythritol toward 3-butene-1,2-diol is described. The procedure relies on specific assets of multistep continuous flow processing. Detailed mechanistic and computational studies on erythritol show that either 3-butene-1,2-diol or butadiene are obtained in high selectivity and yield on demand, as a function of the DODH reagent/substrate ratio and of the process parameters. Short reaction times (1-15 min) at high temperature (225-275 °C) and moderate pressure are reported. 3-Butene-1,2-diol is then further converted downstream into its corresponding carbonate, i.e. 4-vinyl-1,3-dioxolan-2-one (vinyl ethylene carbonate), an important industrial building block. The carbonation step uses a supported organocatalyst, and could be directly concatenated to the first DODH step. This unprecedented procedure also relies on a unique combination of on- and off-line analytical protocols for reaction monitoring and product quantification, and offers a biobased strategy toward important industrial building blocks otherwise petrosourced.
- Tshibalonza, Nelly Ntumba,Gérardy, Romaric,Alsafra, Zouheir,Eppe, Gauthier,Monbaliu, Jean-Christophe M.
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supporting information
p. 5147 - 5157
(2018/11/26)
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- Enzyme-mediated enantioselective hydrolysis of 1,2-diol monotosylate derivatives bearing an unsaturated substituent
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We have succeeded in the easy preparation of optically active 1,2-diol monotosylates bearing an unsaturated substituent via enzymatic hydrolysis. Lipase PS quickly catalyzes the hydrolyses of 2-acetoxybut-3-enyl tosylate, which has a double bond, and 2-acetoxybut-3-ynyl tosylate, which has a triple bond, with excellent enantioselectivity to afford the corresponding optically active compounds. The reaction is also applicable to acetates with a longer chain, which has a double bond at the terminus. To demonstrate the applicability of this method, enantiomerically pure (R)-massoialactone, a natural coconut flavor, has been synthesized from racemic 2-acetoxypent-4-enyl tosylate in several steps. Furthermore, the enzyme can recognize the stereochemistry of olefins, and the (Z)-alkenyl structure is more suitable for the enantioselective hydrolysis than the (E)-isomer.
- Matsumoto,Oohana,Hashimoto,Usuda,Shimoda,Ohshima,Suzuki,Togawa
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supporting information
p. 3981 - 3988
(2018/06/15)
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- Formal [5+3] Cycloaddition of Zwitterionic Allylpalladium Intermediates with Azomethine Imines for Construction of N,O-Containing Eight-Membered Heterocycles
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A formal [5+3] cycloaddition of zwitterionic allylpalladium intermediates with 1,3-dipoles is developed, providing N,O-containing eight-membered heterocyclic compounds in high yields. Catalytically generated zwitterionic allylpalladium intermediates in situ from vinylethylene carbonates or vinyloxiranes acted as dipolarophile. (Figure presented.).
- Yuan, Chunhao,Wu, Yang,Wang, Dongqi,Zhang, Zhenhua,Wang, Chang,Zhou, Leijie,Zhang, Cheng,Song, Baoan,Guo, Hongchao
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supporting information
p. 652 - 658
(2017/12/26)
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- Asymmetric Hydroformylation of 4-Vinyl-1,3-dioxolan-2-one
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A chiral cyclic carbonate, 4-vinyl-1,3-dioxolan-2-one was used as racemic substrate in asymmetric hydroformylation. The catalysts were formed in situ from “pre-formed” PtCl2(diphosphine) and tin(II) chloride. (2S,4S)-2,4-Bis(diphenylphosphinopentane ((S,S)-BDPP)), (S,S)-2,3-O-izopropylidine-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane ((S,S)-DIOP)), and (R)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl ((R)-BINAP)) were used as optically active diphosphine ligands. The platinum-containing catalytic systems provided surprisingly high activity. The hydroformylation selectivities of up to 97% were accompanied by perfect regioselectivity towards the dioxolane-based linear aldehyde. The enantiomeric composition of all components in the reaction mixture was determined and followed throughout the reaction. The unreacted 4-vinyl-1,3-dioxolan-2-one was recovered in optically active form. The kinetic resolution was rationalized using the enantiomeric composition of the substrate and the products.
- Pongrácz, Péter,Kollár, László
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p. 1430 - 1436
(2017/03/27)
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- Modular Construction of Protected 1,2/1,3-Diols, -Amino Alcohols, and -Diamines via Catalytic Asymmetric Dehydrative Allylation: An Application to Synthesis of Sphingosine
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A new enantioselective catalysis has been developed for the one-step construction of methylene-bridged chiral modules of 1,2- and 1,3-OH and/or NH function(s) from δ- or λ-OH/NHBoc-substituted allylic alcohols and H2C=O / H2C=NBoc . A protonic nucleophile, either in situ-generated CH2OH or CH2NHBoc, is intramolecularly allylated to furnish eight possible 1,2- or 1,3-O,O, -O,N, -N,O, and -N,N chiral modules equipped with an ethenyl group in high yields and enantioselectivities. The utility of this method has been demonstrated in the five-step synthesis of sphingosine.
- Tanaka, Shinji,Gunasekar, Ramachandran,Tanaka, Tatsuya,Iyoda, Yoko,Suzuki, Yusuke,Kitamura, Masato
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p. 9160 - 9170
(2017/09/11)
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- METHOD FOR PRODUCING ALLYL ALCOHOLS
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PROBLEM TO BE SOLVED: To provide a method for producing allyl alcohols by direct addition of water to a raw material olefin which can achieve both high selectivity of compounds and high yield. SOLUTION: In a method for producing allyl alcohols by direct addition of water to a raw material olefin, the raw material olefin and water are brought into contact with a solid catalyst, where a catalytically active component containing at least one transition metal element selected from groups 8-10 of the periodic table is carried on an oxide carrier, in the presence of oxygen to convert the raw material olefin to allyl alcohols. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
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Paragraph 0078
(2017/05/27)
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- Versatile PdTe/C catalyst for liquid-phase oxidations of 1,3-butadiene
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A commercial Pd catalyst based on Sibunit carbon support was treated with H6TeO6 in a reducing media to obtain a Te coating on the surface of Pd particles. The PdTe/C catalyst prepared in this way showed the ability to control the radical chain oxidation of 1,3-butadiene by promoting the selective formation of 2-butene-1,4-diol, 4-hydroxybut-2-enal and furan in DMA (total selectivity of 61% and yield of 7%). At the same time, the catalyst induced oxidation of 1,3-butadiene by a non-radical heterolytic mechanism involving the formation of two groups of primary products: (1) crotonaldehyde and methyl vinyl ketone and (2) the products of oxygenation at the 1,4-positions. The compounds of the second group including 1,4-dimethoxy-2-butene and maleic acid dimethyl ester were formed on PdTe centers in MeOH. Increasing the Te concentration in the PdTe/C catalyst forced the conversion of 1,3-butadiene toward 1,4-oxygenation and simultaneously decreased the intensity of secondary oxidation, resulting in the selective formation of derivatives of the 1,4-oxygenation - 1,4-dimethoxy-2-butene and allenic alcohol methyl ether (total selectivity of 84% and yield of 48%).
- Kuznetsova,Zudin,Kuznetsova,Zaikovskii,Kajitani,Utsunomiya,Takahashi
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- Chirality induction and chiron approaches to enantioselective total synthesis of α-lipoic acid
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Abstract An efficient, short and convenient asymmetric synthesis of (R)-(+)-lipoic acid in seven steps from chiral hydroxy aldehyde with 32.5% overall yield is described. Synthesis of S and R enantiomers of α-lipoic acid from cis-1,4-butene diol derived chiral lactone is reported with 34 % overall yield. The present synthesis involves use of simple reaction conditions making it a convenient synthesis.
- Chavan, Subhash P.,Pawar, Kailash P.,Praveen, Ch.,Patil, Niteen B.
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supporting information
p. 4213 - 4218
(2015/06/02)
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- Transfer hydrogenation of organic formates and cyclic carbonates: An alternative route to methanol from carbon dioxide
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Transfer hydrogenation of organic formates and cyclic carbonates was achieved for the first time using a readily available ruthenium catalyst. Nontoxic and economical 2-propanol was used, both as a solvent and hydrogen source, without the need of using flammable H2 gas under high pressure. This method provides an indirect strategy to produce methanol from carbon dioxide under mild conditions as well as an operationally simple and environmentally benign way to reduce formates and carbonates.
- Kim, Seung Hyo,Hong, Soon Hyeok
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p. 3630 - 3636
(2015/02/19)
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- Expedient synthesis of epigoitrin from L-ascorbic acid
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Epigoitrin is the main bioactive constituent of an important traditional Chinese herbal medicine, Radix isatidis. Reported pharmacological effects of epigoitrin include antiviral, anticancer, and antithyroid activities. Extensive biological exploration of
- Yang, Jing-Jing,Wu, Jian-Zhong,Qiao, Chunhua
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supporting information
p. 1240 - 1244
(2014/04/17)
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- 1,3-Dimethylimidazolium-2-carboxylate: A zwitterionic salt for the efficient synthesis of vicinal diols from cyclic carbonates
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The development of efficient, cheap and recyclable catalysts for reactions under mild reaction conditions is a very attractive topic in green chemistry. Herein, a series of basic ionic liquids (ILs) were investigated as catalysts for the synthesis of vicinal diols via the hydrolysis of cyclic carbonates in order to improve this kind of synthetic process. The effects of the IL structure, the molar ratio of cyclic carbonate to water, and various reaction parameters on the catalytic performance were investigated in detail. It was found that 1,3-dimethylimidazolium-2-carboxylate, a simple halogen-free zwitterionic catalyst, showed high activity (a space-time yield of 1086 h-1) and excellent selectivity for the preparation of ethylene glycol via the hydrolysis of ethylene carbonate. The catalyst could be reused over six times without obvious loss of catalytic activity. Also, it was applicable to a variety of cyclic carbonates for the production of their corresponding vicinal diols with high yields and selectivities. A possible catalytic cycle for this kind of catalytic process was proposed based on the experimental results, NMR spectroscopy and theoretical calculations. This reaction protocol opens a new possibility for chemical synthesis as a substitution for traditional base or basic ILs. This journal is the Partner Organisations 2014.
- Sun, Jian,Yao, Xiaoqian,Cheng, Weiguo,Zhang, Suojiang
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p. 3297 - 3304
(2014/06/10)
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- Preparation of enantioenriched tetraols and triolamines from a common epoxide
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We identify a silylcyclopentene oxide that is amenable to several distinct asymmetric catalytic transformations providing access to enantio-enriched tetraol and triol-amines. The sequence employed allows for selective protection of one amine or alcohol from the four heteroatoms that are introduced into the carbon scaffold.
- Kaviani-Joupari, Makan,Schramm, Michael P.
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supporting information
p. 5014 - 5017
(2013/09/02)
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- Catalytic properties of heteropoly compounds in 1,3-butadiene oxidation with hydrogen peroxide
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The homogeneous oxidation of 1,3-butadiene (BD) in H2O 2-HPC-CH3CN (HPC = heteropoly compound) solutions has been investigated. The route of the reaction depends on the nature of the metal capable of coordinating with active oxygen in the HPC. The products of radical BD oxidation (acrolein, 3-butene-1,2-diol, 2-butene-1,4-diol, furan) form in the presence of H3+n PMo12 - n V n O40 (n = 1, 2) acids. 3,4-Epoxy-1-butene (EB) and acrolein + furan, which form in equal amounts in the presence of the (n-Bu4N)5PW 11O39Fe(OH) salt, result, respectively, from the electrophilic addition of hydrogen peroxide to BD and from radical BD oxidation on iron-oxygen complexes in the HPC composition. The reaction carried out in the presence of (n-Bu4N)3{PO4[WO(O 2)2]4}, (n-Bu4N)5Na 0.6H1.4PW11O39, or (EMIm) 5NaHPW11O39 yields EB with high selectivity on the reacted BD basis (up to 97%) and H2O2 (about 100%). The formation and conversion of the phosphotungstate peroxo complexes PW n O m α- (n = 2, 3, 4) that are active in BD epoxidation have been investigated by 31PNMR spectroscopy. The role of the tetrabutylammonium and ethylmethylimidazolium cations in the formation of these complexes has been demonstrated.
- Kuznetsova,Kuznetsova,Maksimovskaya,Koshcheeva,Utkin
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p. 420 - 430
(2013/12/04)
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- Asymmetric synthesis of a 12-membered macrolactone core and a 6-epi analogue of amphidinolide W from 4-pentenoic acid
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A flexible and efficient asymmetric route to the synthesis of a 12-membered macrolactone core and a 6-epi analogue of amphidinolide W has been accomplished from commercially available 4-pentenoic acid. The successful generation of stereocenters was achieved by utilizing an Evans' chiral auxiliary-based alkylation and aldol reaction. Other key reactions such as a Julia-Kocienski olefination, Kita's macrolactonization, ring closing metathesis (RCM) reaction, and Yamaguchi's esterification were significant for the construction of the macrolactone cores.
- Chatterjee, Bhaskar,Mondal, Dhananjoy,Bera, Smritilekha
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p. 1170 - 1185,16
(2020/09/09)
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- Synthesis and stereospecificity of 4,5-disubstituted oxazolidinone ligands binding to T-box riboswitch RNA
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The enantiomers and the cis isomers of two previously studied 4,5-disubstituted oxazolidinones have been synthesized, and their binding to the T-box riboswitch antiterminator model RNA has been investigated in detail. Characterization of ligand affinities and binding site localization indicates that there is little stereospecific discrimination for binding antiterminator RNA alone. This binding similarity between enantiomers is likely due to surface binding, which accommodates ligand conformations that result in comparable ligand-antiterminator contacts. These results have significant implications for T-box antiterminator-targeted drug discovery and, in general, for targeting other medicinally relevant RNA that do not present deep binding pockets.
- Orac, Crina M.,Zhou, Shu,Means, John A.,Boehm, David,Bergmeier, Stephen C.,Hines, Jennifer V.
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scheme or table
p. 6786 - 6795
(2011/12/04)
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- Asymmetric total synthesis of (2S,3S)-3-hydroxypipecolic acid
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A synthetic route to (2S,3S)-3-hydroxypipecolic acid was achieved from readily available nonchiral pool starting material cis-2-butene-1,4-diol and involved Claisen orthoester rearrangement, Sharpless asymmetric dihydroxylation and intramolecular lactamisation of azido lactone as the key steps.
- Chavan, Subhash P.,Dumare, Nilesh B.,Harale, Kishor R.,Kalkote, Uttam R.
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scheme or table
p. 404 - 406
(2011/02/28)
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- Three step synthesis of single diastereoisomers of the vicinal trifluoro motif
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A three step route to single diastereoisomers of the vicinal trifluoromethyl motif is described. The route starts from either syn- or anti-α,β-epoxy alcohols and takes a direct approach in that each of the three steps introduces a fluorine atom in a regio- and stereospecific manner. Starting from either the syn- or the anti-α,β-epoxy alcohol, stereospecific reactions generate two separate diastereoisomeric series of this motif. The route is a significant improvement on an earlier six step strategy.
- Brunet, Vincent A.,Slawin, Alexandra M. Z.,O'Hagan, David
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supporting information; experimental part
(2010/04/22)
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- "Cassette" in situ enzymatic screening identifies complementary chiral scaffolds for hydrolytic kinetic resolution across a range of epoxides
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(Figure Presented) Put the cassette in: An in situ enzymatic screen can give real-time estimates of the sense and magnitude of enantioselectivity across more than one substrate. Screening identified CoIII-salen catalysts with β-pinene- and α-naphthylalanine-derived chiral scaffolds with broad, yet complementary, substrate specificities. ADH = alcohol dehydrogenase, HL = horse liver, LK = Lactobacillus kefir, salen = (salicylidene) ethylenediamine.
- Dey, Sangeeta,Powell, Douglas R.,Hu, Chunhua,Berkowitz, David B.
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p. 7010 - 7014
(2008/09/17)
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- METHOD FOR PRODUCING UNSATURATED VICINAL DIOL COMPOUND
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A method for producing an unsaturated vicinal diol compound represented by the formula (2): wherein R1, R2, R3 R4, R5 and R6 are the same or different and each independently represent a hydrogen atom; a C1-C20 alkyl group which may be substituted with a halogen atom or atoms, a C1-C6 alkoxy group or groups, a C2-C7 alkoxycabonyl group or groups, a C6-C10 aryl group or groups, or a carboxyl group or groups; or a C6-C10 aryl group which may be substituted with a halogen atom or atoms, a C1-C6 alkoxy group or groups, a C6-C10 aryl group or groups, or a carboxyl group or groups, which comprises reacting an unsaturated epoxy compound represented by the formula (1): wherein R1, R2, R3, R4, R5 and R6 are the same as defined above, with water in the presence of a silicate containing at least one element selected from a group 5 element and a group 6 element of the long periodic table as a constituent.
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Page/Page column 7; 8
(2008/06/13)
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- Synthesis of diols from 1,2-epoxy-3-butene
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The catalytic hydration of 1,2-epoxy-3-butene was studied. The products of the reaction are 3-butenediol-1,2(BD-1,2) and 2-butenediol-1,4 (BD-1,4). It was shown that the formation of 2-butenediol-1,4 proceeds predominantly in a polar solvent medium in the presence of the catalytic system "nickel iodide (bromide)-tetraethylammonium iodide" at a temperature of 80°C. In the presence of inorganic acids, the main product is 3-butenediol-1,2. Nauka/Interperiodica 2007.
- Mel'nik,Srednev,Rybina,Meshechkina,Shevchuk,Danilova
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p. 201 - 204
(2008/09/21)
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- Preparation of 2,3,4-trihydroxybutylarsonic acid: A starting compound for novel arsonolipids
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Possible routes for the preparation of 2,3,4-trihydroxybutylarsonic acid, a key compound for the synthesis of novel arsonolipids, were experimentally evaluated. The best substrate was found to be 3,4-epoxybutane-1,2-diol. Its reaction with alkaline sodium arsenite, "Na3AsO3," gave the arsonic acid in 50% yield, as two pairs of diastereoisomers, each pair being a racemic mixture. Copyright Taylor & Francis Group, LLC.
- Lala, Maria A.,Tsivgoulis, Gerasimos M.,Ioannou, Panayiotis V.
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p. 2747 - 2760
(2008/12/22)
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- METHOD FOR PRODUCING 2-HYDROXY-4-(METHYLTHIO)BUTANOIC ACID
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A method for producing 2-hydroxy-4-(methylthio)butyric acid which comprises the following steps (A), (B) and (C): Step (A): step of reacting 1,2-epoxy-3-butene with water to obtain 3-butene-1,2-diol, Step (B): step of reacting 3-butene-1,2-diol with methanethiol to obtain 4-(methylthio)butane-1,2-diol, Step (C): step of oxidizing 4-(methylthio)butane-1,2-diol to obtain 2-hydroxy-4-(methylthio)butyric acid.
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- The preparation of enantiomerically pure 3,4-epoxy-1-butene and 3-butene-1,2-diol
-
Single enantiomer 2-hydroxy-3-butenyl tosylate is a key precursor for single enantiomer 3,4-epoxy-1-butene and 3-butene-1,2-diol. The epoxide results from ring-closure of the hydroxytosylate while the diol is obtained through the intermediacy of the corresponding cyclic carbonate. This latter sequence avoids the loss of enantiomeric purity observed through direct hydrolysis. Georg Thieme Verlag Stuttgart.
- Boaz, Neil W.,Falling, Stephen N.,Moore, Mary K.
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p. 1615 - 1617
(2007/10/03)
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- Enzymatic resolution of 1,1-dimethoxybut-3-en-2-ol and 1,1-dimethoxypent-4- en-2-ol, α-hydroxyaldehyde precursors for aldol-type reactions
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Hydroxyacetals 2 and 3 were resolved by acylation with vinyl acetate in the presence of lipases in organic media. The reverse reaction, the enzymatic hydrolysis of the corresponding acetates, was also highly stereoselective and provided the opposite enant
- Chenevert, Robert,Gravil, Sebastien,Bolte, Jean
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p. 2081 - 2086
(2007/10/03)
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- Synthesis of the fully functionalized ABCDE ring moiety of ciguatoxin
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A fully functionalized ABCDE ring moiety of ciguatoxin (CTX), the major causative agent of ciguatera poisoning, was synthesized for the first time. The present strategy involves the efficient installation of the C5-dihydroxybutenyl substituent and constru
- Kobayashi, Shoji,Alizadeh, Babak H.,Sasaki, Shin-Ya,Oguri, Hiroki,Hirama, Masahiro
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p. 751 - 754
(2007/10/03)
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- Industrialization of the Microbial Resolution of Chiral C3 and C4 Synthetic Units: From a Small Beginning to a Major Operation, a Personal Account
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This account describes the research and development of the microbial resolution of chiral C3 and C4 synthetic units through to the production stage. These chiral C3 and C4 synthetic units are mainly used for the production of various pharmaceuticals, new materials such as liquid crystals, chiral polymers, and natural compounds as well as in basic chemical research. The research started in 1983 and the industrial plant was built in 1994. The development is still ongoing and is being broadened to include C4 chiral units, chiral propylene glycol, and so on. This project started as simple research on the activated sludge from an epichlorohydrin plant and evolved through many events and much research to an industrial production. We describe the various implications and the flow of events in the research and development through to the production of these chiral C3 and C4 synthetic units.
- Kasai, Naoya,Suzuki, Toshio
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p. 437 - 455
(2007/10/03)
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- Highly selective hydrolytic kinetic resolution of terminal epoxides catalyzed by chiral (salen)CoIII complexes. Practical synthesis of enantioenriched terminal epoxides and 1,2-diols
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The hydrolytic kinetic resolution (HKR) of terminal epoxides catalyzed by chiral (salen)CoIII complex 1·OAc affords both recovered unreacted epoxide and 1,2-diol product in highly enantioenriched form. As such, the HKR provides general access to useful, highly enantioenriched chiral building blocks that are otherwise difficult to access, from inexpensive racemic materials. The reaction has several appealing features from a practical standpoint, including the use of H2O as a reactant and low loadings (0.2-2.0 mol %) of a recyclable, commercially available catalyst. In addition, the HKR displays extraordinary scope, as a wide assortment of sterically and electronically varied epoxides can be resolved to ≥ 99% ee. The corresponding 1,2-diols were produced in good-to-high enantiomeric excess using 0.45 equiv of H2O. Useful and general protocols are provided for the isolation of highly enantioenriched epoxides and diols, as well as for catalyst recovery and recycling. Selectivity factors (krel) were determined for the HKR reactions by measuring the product ee at ca. 20% conversion. In nearly all cases, krel values for the HKR exceed 50, and in several cases are well in excess of 200.
- Schaus, Scott E.,Brandes, Bridget D.,Larrow, Jay F.,Tokunaga, Makoto,Hansen, Karl B.,Gould, Alexandra E.,Furrow, Michael E.,Jacobsen, Eric N.
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p. 1307 - 1315
(2007/10/03)
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- Effect of a proximal oxygen substituent on the efficacy of ruthenium-catalyzed cross-metathesis and RCM
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Ruthenium-catalyzed cross-metathesis of various derivatives of 1,2-dihydroxy-3-butene reveals that cyclic acetals are best suited as substrates compared to acyclic diethers or diacetates, while RCM is relatively insensitive to the presence of allylic or homoallylic hydroxy or acetoxy groups.
- Maishal, Tarun K,Sinha-Mahapatra, Dilip K,Paranjape, Kavita,Sarkar, Amitabha
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p. 2263 - 2267
(2007/10/03)
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- A chemoenzymatic approach to the synthesis of the stereoisomers of a β-adrenergic receptor antagonist
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The four stereoisomers of Δ2-isoxazoline 2, a β-adrenergic receptor antagonist structurally related to Falintolol 1, were prepared by an enzyme-catalyzed kinetic resolution of the unsaturated secondary alcohol (±)-7 followed by its cycloadditio
- Dallanoce, Clelia,De Amici, Marco,Carrea, Giacomo,Secundo, Francesco,Castellano, Sabrina,De Micheli, Carlo
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p. 2741 - 2751
(2007/10/03)
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- Bacterial biotransformation of isoprene and related dienes
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The bacterium Pseudomonas putida ML 2 was used in the oxidative biodegradation of the acyclic dienes isoprene, trans-piperylene, cis-piperylene, and 1,3-butadiene. Regioselective dioxygenase-catalyzed dihydroxylation of alkenes yielded vicinal diols in the preferred sequence monosubstituted 〉 cis-disubstituted 〉 gem-disubstituted 〉 trans-disubstituted. The isolated diol metabolites had an excess of the R configuration (9-97% ee), and further diol oxidation was controlled by addition of propylene glycol as an inhibitor. Stereoselectivity using the ML2 strain resulted from both enzymatic asymmetric alkene dihydroxylation and kinetic resolution of diols. Enantioselective oxidation of the allylic secondary alcohol group of R configuration yielded the corresponding unsaturated ketoalcohol; the residual diol was recovered with a large excess (≥ 93% ee) of the S configuration. In addition to the enzymatic diene oxidation steps yielding unsaturated diols and ketoalcohols, evidence was also found of enzymatic alkene hydrogenation to yield saturated ketoalcohols and diols.
- Boyd, Derek R.,Clarke, David,Cleij, Marcel C.,Hamilton, John T.G.,Sheldrake, Gary N.
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p. 673 - 685
(2007/10/03)
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- Isomerization of allylic silyl ethers catalyzed by ReO3(OSiR3) complexes
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Efficient isomerization of allylic alcohols and allylic ethers at room temperature by rhenium (VII) oxo complexes is described. (C) 2000 Elsevier Science Ltd.
- Bellemin-Laponnaz, Stéphane,Le Ny, Jean Pierre,Osborn, John A.
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p. 1549 - 1552
(2007/10/03)
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- New synthesis of sn-1,2- and sn-2,3-O-diacylglycerols application to the synthesis of enantiopure phosphonates analogous to triglycerides: A new class of inhibitors of lipases
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Phosphonate compounds mimic the first transition state occurring during enzymatic carboxyester hydrolysis of natural substrates by forming a covalent bond with the catalytic serine. However, until now the organophosphorus compounds used in the inhibition studies more or less resembled a natural triglyceride substrate. In order to elucidate the interfacial activation and the mechanism of action of lipases, specific inhibitors need to be prepared. To achieve this goal, enantiomerically pure sn-1,2- and sn-2,3O- didecanoylglycerol compounds were prepared - starting from a C-4 chiral synthon, 3-buten-1,2-diol - and treated with n-pentylphosphonic dichloride and p-nitrophenol to afford the corresponding diastereomeric phosphonates, which were acylglycerol analogs. Subsequent separation of each of the phosphonate diastereomers A/B or ent-A/ent-B, performed by HPLC, led to four enantiopure stereoisomers that will be investigated as inhibitors of Human Pancreatic Lipase (HPL) and Human Gastric Lipase (HGL) using the monomolecular film technique.
- Marguet, Frank,Cavalier, Jean-Francois,Verger, Robert,Buono, Gerard
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p. 1671 - 1678
(2007/10/03)
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- Acylnitrene route to vicinal amino alcohols. Application to the synthesis of (-)-bestatin and analogues
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Bestatin, valinoctin A, and microginin are naturally occurring small peptides containing a nonproteinogenic α-hydroxy-α-amino acid at the N-terminus of the peptide chain. We report here our development of a general method for the synthesis of α-hydroxy-β-amino acids and exemplify this with a synthesis of (-)-bestatin and analogues. Our synthesis utilizes an intramolecular acylnitrene-mediated aziridination to generate a key bicyclic aziridine in excellent yield and stereoselectivity. This bicyclic aziridine can be opened with a number of organometallic reagents to provide a series of substituted oxazolidinones. The oxazolidinones are readily converted to bestatin and a series of bestatin analogues. As part of this approach, we have developed a new method for the synthesis of azidoformates. We have also demonstrated that oxazolidinones can be selectively hydrolyzed in the presence of peptide bonds. This acylnitrene route to bestatin should prove useful for the synthesis of a variety of analogues of bestatin as well as other α-hydroxy-β-amino acids and their corresponding peptides.
- Bergmeier, Stephen C.,Stanchina, Dionne M.
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p. 2852 - 2859
(2007/10/03)
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- Kinetic chiral resolutions of 1,2-diols and desymmetrization of glycerol catalyzed by glycerol kinase
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Enantioselective phosphorylation catalyzed by glycerol kinase (EC 2.7.1.30) facilitated the kinetic chiral resolution of 3-chloro-1,2- propanediol, 3-fluoro-1,2-propanediol, 3-butene-1,2-diol, and 1,2,4- butanetriol. Both enantiomers of each compound were isolated is free diol or triol form, in excellent enantiomeric purity (91 to > 99.5% ee) and in moderate to good yield (60-94% of theoretical). The enantioselectivities of glycerol kinase from different sources were compared using 1,2,4-butanetriol as the substrate. The effect of elevated temperatures on enzymatic activity, stability, and enantioselectivity were studied, and procedures for the isolation of diol and triol products were optimized. Glycerol kinase- catalyzed phosphorylation facilitated the three-step chemoenzymatic conversion of glycerol to (S)-1,2-O-isopropylideneglycerol in 83% yield and > 99.5% ee).
- Keith Chenault,Chafin, Laura F.,Liehr, Sebastian
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p. 4039 - 4045
(2007/10/03)
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- Isomerization of vinyl glycols to unsaturated diols
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This invention relates to a process for the isomerization of a vinyl glycol to an unsaturated diol in the presence of a rhenium-based catalyst; and to a catalyst for said isomerization. More specifically, this invention relates to the isomerization of 3-butene-1,2-diol to 2-butene-1,4-diol; and to a process for the manufacture of 1,4-butanediol involving the step of isomerizing 3-butene-1,2-diol to 2-butene-1,4-diol in the presence of said catalyst. The catalyst is characterized in that it comprises a transition metal on a carrier wherein the carrier is a zeolite Y type substance containing silicon and aluminum in a mole ratio of from about 1.5:1 to about 1000:1, and the transition metal is rhenium or a rhenium compound and mixtures thereof present in an amount of from about 0.1 to about 50 weight percent based on total combined weight of the carrier and of the rhenium or rhenium compound and mixtures thereof.
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- Iodide assisted zeolite catalysed 1,4-addition of water to butadiene monoxide
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Selective 1,4-addition of water to butadiene monoxide can be achieved in a liquid phase catalytic process using ultrastable Y zeolite as Broensted acid, potassium iodide, and an ether solvent. The reaction mechanism could be elucidated based on the occurrence of intermediate reaction products. Iodide is added to the terminal unsaturated carbon atom of a protonated butadiene monoxide molecule. The strong solvent effect observed can be rationalised based on the nucleophilicity of the iodide depending on the basicity of the ether function. With USY zeolite, the 2-butene-1,4-diol selectivity reaches 73.9% at 100% conversion when using 1,2-dimethoxyethane solvent, 2,5-dihydrofuran being the main by-product. With this catalytic system followed by an additional hydrogenation step, butadiene monoxide can be selectively converted into 1,4-butanediol.
- Remans, Thomas J.,Van Oeffelen, Domien,Steijns, Matt,Martens, Johan A.,Jacobs, Pierre A.
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p. 312 - 315
(2007/10/03)
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- In vitro and in vivo mutagenicity of the butadiene metabolites butadiene diolepoxide, butadiene monoepoxide and diepoxybutane
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Three metabolites of 1,3-butadiene, namely butadiene diolepoxide, butadiene monoepoxide and diepoxybutane, were tested in the bacterial mutation assay using Salmonella typhimurium Strain TA100 with and without metabolic activation (S9 mix). All three compounds showed a mutagenic response. The bifunctional epoxide was more effective than the diolepoxide which was more effective than the monoepoxide. Toxicity appeared to follow the ranking of the chemicals for their mutagenic potency. The monoepoxide and the diolepoxide were also tested for induction of micronuclei in mouse bone marrow erythrocytes and for dominant lethal mutation induction in postmeiotic male mouse germ cells. The effects of the diepoxide in both in vivo tests have been published earlier. In the micronucleus assay, the three metabolites gave a positive response whereby the diepoxide was more effective than the monoepoxide which was more effective than the diolepoxide. In contrast to the diepoxide which was positive at a dose as low as 36 mg/kg, the monoepoxide and the diol did not show an induction of dominant lethal effects up to doses of 120 and 240 mg/kg, respectively. It is concluded that the metabolites were mutagenic in bacteria without metabolic activation and clastogenic in mouse bone marrow; only the bifunctional diepoxide, however, was active in postmeiotic male mouse germ cells.
- Adler,Kliesch,Nylund,Peltonen
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p. 339 - 345
(2007/10/03)
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