- An In-Situ Self-regeneration Catalyst for the Production of Renewable Penta-1,3-diene
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Catalyst deactivation is a problem of great concern for many heterogeneous reactions. Here, an urchin-like LaPO4 catalyst was easily developed for pentane-2,3-diol dehydration; it has an impressive ability to restore the activity in situ by itself during the reaction, accounting for its high stability. This facilitates the efficient production of renewable penta-1,3-diene from pentane-2,3-dione via a novel approach, where penta-2,3-diol was obtained as an intermediate in 95 % yield under mild conditions.
- Feng, Ruilin,Qi, Yanlong,Liu, Shijun,Cui, Long,Dai, Quanquan,Bai, Chenxi
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supporting information
p. 9495 - 9498
(2021/05/27)
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- Synthesis method of pentanediol and synthesis method for preparing biomass-based linear pentadiene based on lactic acid conversion
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The invention provides a method for synthesizing pentanediol. The method comprises the following steps: carrying out hydrogenation reaction on a mixed solution obtained by mixing pentanedione, a hydrogenation catalyst and an organic solvent in a hydrogen-containing atmosphere to obtain the pentanediol. According to the invention, a large amount of cheap and easily available bio-based chemical lactic acid can be utilized to obtain pentanediol, and linear pentadiene is further obtained; the raw materials are from renewable resources, and linear pentadiene is obtained through the following steps: (1) condensing lactic acid to prepare pentanedione, (2) hydrogenating pentanedione to prepare pentanediol, and (3) dehydrating pentanediol to obtain linear pentadiene; linear pentadiene, especially 1, 3-pentadiene, is prepared from lactic acid through a process route of condensation, hydrogenation and dehydration; and a green and sustainable linear pentadiene synthesis method based on bio-based chemical conversion is provided, and is simple to operate, short in process, free of harsh experimental conditions, easy to prepare raw materials and catalysts, and has a large-scale synthesis prospect.
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Paragraph 0204; 0207-0208; 0211; 0214-0215; 0218; 0221-0222
(2021/05/19)
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- Hydrodeoxygenation of C4-C6 sugar alcohols to diols or mono-alcohols with the retention of the carbon chain over a silica-supported tungsten oxide-modified platinum catalyst
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The hydrodeoxygenation of erythritol, xylitol, and sorbitol was investigated over a Pt-WOx/SiO2 (4 wt% Pt, W/Pt = 0.25, molar ratio) catalyst. 1,4-Butanediol can be selectively produced with 51% yield (carbon based) by erythritol hydrodeoxygenation at 413 K, based on the selectivity over this catalyst toward the regioselective removal of the C-O bond in the -O-C-CH2OH structure. Because the catalyst is also active in the hydrodeoxygenation of other polyols to some extent but much less active in that of mono-alcohols, at higher temperature (453 K), mono-alcohols can be produced from sugar alcohols. A good total yield (59%) of pentanols can be obtained from xylitol, which is mainly converted to C2 + C3 products in the literature hydrogenolysis systems. It can be applied to the hydrodeoxygenation of other sugar alcohols to mono-alcohols with high yields as well, such as erythritol to butanols (74%) and sorbitol to hexanols (59%) with very small amounts of C-C bond cleavage products. The active site is suggested to be the Pt-WOx interfacial site, which is supported by the reaction and characterization results (TEM and XAFS). WOx/SiO2 selectively catalyzed the dehydration of xylitol to 1,4-anhydroxylitol, whereas Pt-WOx/SiO2 promoted the transformation of xylitol to pentanols with 1,3,5-pentanetriol as the main intermediate. Pre-calcination of the reused catalyst at 573 K is important to prevent coke formation and to improve the reusability.
- Betchaku, Mii,Cao, Ji,Liu, Lujie,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi,Yabushita, Mizuho
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supporting information
p. 5665 - 5679
(2021/08/16)
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- Synthesis of α-hydroxy ketones and vicinal (R, R)-diols by Bacillus clausii DSM 8716T butanediol dehydrogenase
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α-hydroxy ketones (HK) and 1,2-diols are important building blocks for fine chemical synthesis. Here, we describe the R-selective 2,3-butanediol dehydrogenase from B. clausii DSM 8716T (BcBDH) that belongs to the metal-dependent medium chain dehydrogenases/reductases family (MDR) and catalyzes the selective asymmetric reduction of prochiral 1,2-diketones to the corresponding HK and, in some cases, the reduction of the same to the corresponding 1,2-diols. Aliphatic diketones, like 2,3-pentanedione, 2,3-hexanedione, 5-methyl-2,3-hexanedione, 3,4-hexanedione and 2,3-heptanedione are well transformed. In addition, surprisingly alkyl phenyl dicarbonyls, like 2-hydroxy-1-phenylpropan-1-one and phenylglyoxal are accepted, whereas their derivatives with two phenyl groups are not substrates. Supplementation of Mn2+ (1 mM) increases BcBDH's activity in biotransformations. Furthermore, the biocatalytic reduction of 5-methyl-2,3-hexanedione to mainly 5-methyl-3-hydroxy-2-hexanone with only small amounts of 5-methyl-2-hydroxy-3-hexanone within an enzyme membrane reactor is demonstrated.
- Bongaerts, Johannes,Jablonski, Melanie,Kipp, Carina Ronja,Molinnus, Denise,Muschallik, Lukas,Pohl, Martina,Sch?ning, Michael J.,Selmer, Thorsten,Siegert, Petra,Wagner, Torsten
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p. 12206 - 12216
(2020/04/20)
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- Method for synthesizing o-glycol compounds by virtue of bifunctional characteristic catalyst
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The invention belongs to the technical field of organic chemical synthesis and particularly relates to a method for synthesizing o-glycol compounds by virtue of a bifunctional characteristic catalyst.The o-glycol compounds are prepared from olefin and an oxidizing agent through reaction under the effect of the bifunctional characteristic catalyst, wherein the bifunctional characteristic catalystcontains the following components in percentage by mass: 25%-75% of a titanium silicalite molecular sieve, 20%-70% of nano-silicon dioxide and 5%-10% of heteropolyacid. The method provided by the invention has the beneficial effects that a process for synthesizing o-glycol by virtue of a traditional two-step method is simplified; the catalyst can still remain good catalytic performance under a long-period operation condition in the method, the raw material conversion rate is high, and the yields of the o-glycol compounds are high; and the olefin raw material conversion rate is 80.2%-94.6%, andthe selectivity of o-glycol generated through reaction is 85.7%-96.3%.
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Paragraph 0034-0035; 0036-0037; 0039-0045
(2018/04/26)
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- Method for synthesizing vicinal diol compound by virtue of one-step process
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The invention belongs to the technical field of organic chemical synthesis, and in particular relates to a method for synthesizing a vicinal diol compound by virtue of a one-step process. The vicinaldiol compound is obtained by carrying out reaction on olefin and an oxidizing agent in presence of a bifunctional catalyst, wherein the bifunctional catalyst comprises 25-75% of titanium silicalite molecular sieves, 20-70% of nano alumina and 3-8% of boric oxide in percentage by mass with the titanium silicalite molecular sieves, nano alumina and boric oxide as the benchmarks. The method for synthesizing the vicinal diol compound has the advantages that the traditional two-step vicinal diol synthesis technology is simplified; in the synthetic method, a catalyst still maintains good catalytic performance under long-period operation condition, raw material conversion rate is high, and yield of the vicinal diol compound is high; and olefin raw material conversion rate is 80.2-94.6%, and vicinal diol reaction generation selectivity is 85.7-96.3%.
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Paragraph 0032-0041
(2018/04/26)
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- Investigation of the Reaction Pathways of Biomass-Derived Oxygenate Conversion into Monoalcohols in Supercritical Methanol with CuMgAl-Mixed-Metal Oxide
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Reaction pathways for the conversion of cellulose into C2–C6 monoalcohols by supercritical methanol depolymerization and hydrodeoxygenation (SCM-DHDO) over a CuMgAl oxide catalyst have been elucidated using a range of model compounds. SCM-DHDO of intermediate oxygenates including glycerol, methyl lactate, and 1,2-ethanediol produces similar products as those produced from the SCM-DHDO of cellulose. The pathway to C2–C6 monoalcohols occurs through rapid C?C coupling reactions between methanol and diols followed by C?C scission between vicinal alcohol groups to produce two monoalcohols. Methyl-branched monoalcohols are produced through a methyl shift in a secondary diol followed by dehydration. Esters are produced by dehydrogenative coupling between an adsorbed methoxy and a primary alcohol. Both dehydrogenation to a ketone and esterification to a methyl ester are in equilibrium with the corresponding alcohol and were reversible. Dehydration of diols is the slowest observed reaction and not a main pathway to monoalcohols. SCM-DHDO of glucose, dihydroxyacetone, and cellulose all produced similar high molecular weight species indicating that condensation of intermediates can produce undesired side products.
- Galebach, Peter H.,Thompson, Sean,Wittrig, Ashley M.,Buchanan, J. Scott,Huber, George W.
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p. 4007 - 4017
(2018/11/23)
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- Method for synthesizing vicinal diol compound which takes hydrocarbon epoxide as raw material
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The present invention discloses a method for preparing a vicinal diol compound which takes a hydrocarbon epoxide as a raw material. The method takes the hydrocarbon epoxide as the raw material and takes an anion exchange resin as a catalyst. The vicinal diol compound is prepared by using a fixed bed continuous hydrolysis reaction technology. The anion exchange resin is a halogen-substituted macroporous polystyrene-divinyl benzene quaternary ammonium salt type anion exchange resin. The synthesis method is simple, the catalyst can be used many times, the raw material conversion rate is high, and the yield of the vicinal diol compound is high.
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Paragraph 0027-0028; 0032; 0037
(2017/08/03)
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- Method for preparing vicinal diol compound through ring-opening reaction
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The present invention discloses a method for preparing a vicinal diol compound through a ring-opening reaction. The method takes a hydrocarbons epoxide as a raw material and takes an anion exchange resin as a catalyst. The vicinal diol compound is prepared by using a fixed bed continuous hydrolysis reaction technology. The anion exchange resin is a halogen-substituted macroporous polystyrene-divinyl benzene quaternary ammonium salt type anion exchange resin. The synthesis method is simple, the catalyst can be used many times, the raw material conversion rate is high, and the yield of the vicinal diol compound is high.
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Paragraph 0015; 0031; 0033; 0036
(2017/03/28)
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- Method for synthesizing ortho-diol compound by using macroporous anion exchange resin as catalyst
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The invention discloses a method for synthesizing an ortho-diol compound by using macroporous anion exchange resin as a catalyst. According to the method, hydrocarbon epoxide is used as a raw material, the anion exchange resin is used as the catalyst, and a fixed bed continuous hydrolysis reaction technology is adopted for preparing the ortho-diol compound; the anion exchange resin is halogen ortho-substituted macroporous polystyrene-divinyl benzene quaternary phosphonium salt type anion exchange resin. The synthesis method is simple, the catalyst can be used repeatedly, the conversion rate of the raw material is high, and the yield of the ortho-diol compound is high.
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Paragraph 0024; 0025; 0026; 0028; 0029; 0030-0035
(2017/05/27)
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- Method of using anion exchange resin as catalyst to synthesize vicinal diol compound
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The invention discloses a method of using anion exchange resin as a catalyst to synthesize a vicinal diol compound. The method includes: using hydrocarbon epoxide as a raw material and the anion exchange resin as the catalyst; adopting a fixed bed continuous hydrolysis reaction process to obtain the vicinal diol compound, wherein the anion exchange resin is halogen substituted macroporous polystyrene-divinyl benzene quaternary ammonium salt type anion exchange resin. The method is simple, the catalyst can be utilized repeatedly, the raw material is high in conversion rate, and the vicinal diol compound is high in yield.
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Paragraph 0027; 0029; 0030; 0036
(2017/07/06)
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- Synthetic method for o-glycol compounds
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The invention discloses a synthetic method for o-glycol compounds. The method prepares the o-glycol compounds by using a fixed-bed continuous hydrolysis reaction process with hydrocarbon epoxides as raw materials and anion exchange resin as a catalyst, wherein the anion exchange resin is halogen-p-substituted macroporous polystyrene-divinyl benzene quaternary phosphonium salt anion exchange resin. The synthetic method is simple; the catalyst can be repeatedly used a plurality of times; the conversion rate of the raw materials is high; and the yield of the o-glycol compounds is high.
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Paragraph 0026-0027; 0029-0036
(2017/08/28)
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- Facile and highly diastereoselective synthesis of syn- and cis-1,2-diol derivatives from protected α-hydroxy ketones
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An efficient method for the synthesis of monoprotected syn- or cis-1,2-diol derivatives by reduction of easily accessible α-(2,2,6,6-tetramethylpiperidinyloxy) ketones is reported. The α-(tetramethylpiperidinyloxy) group as the stereodirecting group induces in unhindered acyclic or cyclic ketones complete syn- or cis-diastereoselectivity, respectively, with L-Selectride. For more hindered derivatives, where L-Selectride becomes unreactive, LiAlH4 proved effective, essentially showing the same high selectivity. The diastereoselectivity of the reduction can be rationalized for acyclic ketones by the Felkin-Anh model, whereas for cyclic substrates, attack from the face opposite to the tetramethylpiperidinyloxy group predictably prevails with high selectivity regardless of the substitution pattern. The liberation of free diols was achieved by reductive N-O bond cleavage of the alkoxyamine unit. Monoprotected syn- and cis-1,2-diols were synthesized by reduction of ketones bearing the stereodirecting α-(2,2,6,6-tetramethylpiperidinyloxy) group. The latter induces syn- or cis-selectivity in unhindered acyclic or cyclic ketones with L-Selectride, whereas the smaller LiAlH4 induced excellent diastereoselectivity with hindered ketones. Free 1,2-diols were liberated by reductive N-O bond cleavage.
- Jahn, Emanuela,Smr?ek, Jakub,Pohl, Radek,Císa?ová, Ivana,Jones, Peter G.,Jahn, Ullrich
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p. 7785 - 7798
(2015/12/31)
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- Osmium impregnated on magnetite as a heterogeneous catalyst for the syn-dihydroxylation of alkenes
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A new catalyst derived from osmium has been prepared, fully characterized and tested in the dihydroxylation of alkenes. The catalyst was prepared by wet impregnation methodology of OsCl3·3H2O on a commercial micro-magnetite surface. The catalyst allowed the reaction with one of the lowest osmium loadings for a heterogeneous catalyst and was selective for the monodihydroxylation of 1,5-dienes. Moreover, the catalyst was easily removed from the reaction medium by the simple use of a magnet. The selectivity of catalyst is very high with conversions up to 99%. Preliminary kinetics studies showed a first-order reaction rate with respect to the catalyst.
- Cano, Rafael,Pérez, Juana M.,Ramón, Diego J.
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p. 177 - 182
(2014/01/06)
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- Highly efficient and stereoselective biosynthesis of (2S,5S)-hexanediol with a dehydrogenase from Saccharomyces cerevisiae
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The enantiopure (2S,5S)-hexanediol serves as a versatile building block for the production of various fine chemicals and pharmaceuticals. For industrial and commercial scale, the diol is currently obtained through bakers' yeast-mediated reduction of 2,5-hexanedione. However, this process suffers from its insufficient space-time yield of about 4 g L-1 d-1 (2S,5S)-hexanediol. Thus, a new synthesis route is required that allows for higher volumetric productivity. For this reason, the enzyme which is responsible for 2,5-hexanedione reduction in bakers' yeast was identified after purification to homogeneity and subsequent MALDI-TOF mass spectroscopy analysis. As a result, the dehydrogenase Gre2p was shown to be responsible for the majority of the diketone reduction, by comparison to a Gre2p deletion strain lacking activity towards 2,5-hexanedione. Bioreduction using the recombinant enzyme afforded the (2S,5S)-hexanediol with >99% conversion yield and in >99.9% de and ee. Moreover, the diol was obtained with an unsurpassed high volumetric productivity of 70 g L-1 d-1 (2S,5S)-hexanediol. Michaelis-Menten kinetic studies have shown that Gre2p is capable of catalysing both the reduction of 2,5-hexanedione as well as the oxidation of (2S,5S)-hexanediol, but the catalytic efficiency of the reduction is three times higher. Furthermore, the enzyme's ability to reduce other keto-compounds, including further diketones, was studied, revealing that the application can be extended to α-diketones and aldehydes.
- Mueller, Marion,Katzberg, Michael,Bertau, Martin,Hummel, Werner
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experimental part
p. 1540 - 1550
(2010/07/04)
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- Kinetic resolution of 1,2-diols through highly site- and enantioselective catalytic silylation
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(Chemical Equation Presented) Resolved to silylate: A chiral silylation catalyst is used for kinetic resolution of three classes of acyclic 1,2-diols. The catalyst differentiates, with excellent precision, between the two hydroxy groups of a substrate. The majority of the diols, obtained in high enantiomeric purity, cannot be accessed with similar stereochemical purity through catalytic asymmetric dihydroxylation.
- Zhao, Yu,Mitra, Aurpon W.,Hoveyda, Amir H.,Snapper, Marc L.
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p. 8471 - 8474
(2008/09/18)
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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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- Diols obtained via chemo and regioselective ring opening of epoxy alcohols: A straightforward synthesis of 2S,3S-octandiol
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Epoxy alcohols are regio and chemoselectively opened to the corresponding iodohydrins and then reduced in situ to diols; the application of the described procedure leads to a short asymmetric of a well known pheromone. Also homoallylic (E and Z) epoxy alcohols and its benzylated derivatives shows high preference for regioselective opening affording the corresponding 1,3 diol.
- Bonini, Carlo,Righi, Giuliana
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p. 1531 - 1538
(2007/10/02)
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- Baker's Yeast Reduction of 1,2-Diketones. Preparation of Pure (S)-(-)-2-Hydroxy-1-phenyl-1-propanone
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1,2-Diketones are readily reduced by fermenting baker's yeast but the reactions proceed with little selectivity.One notable exception is the reduction of 1-phenyl-1,2-propanedione which affords pure (S)-(-)-2-hydroxy-1-phenyl-1-propanone in good yield.
- Chenevert, Robert,Thiboutot, Sonia
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p. 1191 - 1192
(2007/10/02)
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- Stereochemical Evidence for an Alkylated Perepoxide Intermediate
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Peroxymercuration of (Z)-pent-2-ene afforded single stereoisomers of 2-(bromomercurio)-3-(tert-butylperoxy)pentane (M1) and 3-(bromomercurio)-2-(tert-butylperoxy)pentane (M2), which were separated by medium pressure liquid chromatography.Iodinolysis of each of these gave a pair of epimeric β-iodopentyl tert-butyl peroxides (I1a and I1B from M1, and I2A and I2B from M2), which were similarly separated.When treated with silver trifluoroacetate, the regioisomers I1A and I2A each yielded the same 5:3 mixture of 3-(tert-butylperoxy)-2-(trifluoroacetoxy)pentane (T1) and 2-(tert-butylperoxy)-3-(trifluoroacetoxy)pentane (T2).Independent experiments showed that the starting iodides and the product trifluoroacetates were stereochemically stable under the reaction conditions.Hence, the results are taken to provide compelling evidence for the intermediacy of a tert-butylated perepoxide (PA) that is sufficiently long-lived to be attacked at each ring carbon atom.However, the epimeric regioisomers I1B and I2B each reacted with silver trifluoroacetate to afford a single, new, trifluoroacetate with retention of both regio- and stereochemistry.This is taken to provide evidence for a new mechanism of substitution involving a six-centered cyclic transition state.Product correlations for similar substitutions with analogous bromo peroxides for which stereochemistries are identified by assuming trans addition for peroxymercuration and retention of configuration during bromodemercuration indicate that the alkylated perepoxide (PA) has the structure with cis-alkyl groups.This was confirmed by identifying the stereochemistry of T1 and T2 by LiAlH4 reduction to threo-pentane-2,3-diol.
- Bloodworth, A. J.,Bowyer, Kevin J.,Mitchell, John C.
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p. 1124 - 1128
(2007/10/02)
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- DIASTEREOSELECTIVITY OF THE MERCURATION OF ACYCLIC ALLYLIC ALCOHOLS
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The diastereoselectivity of the mercuration of acyclic alkenes 4 can be reversed by changing the substituent in the allylic position; with alcohols the erythro isomers 5 and with esters or hemiacetals the threo isomers 6 and 8 are formed predominantly (Table I).
- Giese, Bernd,Bartmann, Dieter
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p. 1197 - 1200
(2007/10/02)
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- The Mechanism of Ozone-Alkene Reactions in the Gas Phase. A Mass Spectrometric Study of the Reactions of Eight Linear and Branched-Chain Alkenes
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The stable products of the low-pressure (4 - 8 torr (1 torr = 133.33 Pa)) gas-phase reactions of ozone with ethene, propene, 2-methylpropene, cis-2-butene, trans-2-butene, trans-2-pentene, 2,3-dimethyl-2-butene, and 2-ethyl-1-butene have been identified by using a photoionization mass spectrometer coupled to a stirred-flow reactor.The products observed are characteristic of (i) a primary Criegee split to an oxoalkane (aldehyde or ketone) and a Criegee intermediate, (ii) reactions of the Criegee intermediates such as unimolecular decomposition, secondary ozonide formation, etc., and (iii) secondary alkene chemistry involving OH and other free-radical products formed by the unimolecular decomposition of the Criegee intermediates.The secondary OH - alkene - O2 reactions account for a significant fraction of the alkene (CnH2n) consumed and lead to characteristic products such as Cn dioxoalkanes nH2n + 30)>, Cn acyloins nH2n + 32)>, and Cn alkanediols nH2n + 34)>.Cn oxoalkanes and Cn epoxyalkanes observed at m/e (CnH2n + 16) are probably formed primarily via epoxidation of the alkene by O3.A general mechanism has been proposed to account for the observations.
- Martinez, Richard I.,Herron, John T.,Huie, Robert E.
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p. 3807 - 3820
(2007/10/02)
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- Method for recovering molybdenum catalyst values and use of said values in the recycling of said catalyst
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This application is directed to a method for regenerating catalyst values used in the synthesis of a diol; the synthesis consists of a hydroperoxide reaction with an olefin in the presence of water and a molybdenum catalyst; the regenerating process consists in treating the molybdenum catalyst residue (or a fraction thereof) with ammonia -- optionally after calcining -- and causing a diol to act on the ammonium molybdate so obtained; in one embodiment ammonia in gaseous form is passed in contact with a catalyst residue (not previously calcined) which is in solution; the reaction products in the synthesis of the diol are a hydroperoxide such as tertiary hydroperoxide of isopentane and an olefin such as methyl 2-butene; the diol synthesized in 2-methyl 2,3-butanediol; it is also the synthesized diol which is preferably reacted with the ammonium molybdate.
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