- Multisite catalysis: A mechanistic study of β-lactone synthesis from epoxides and CO - Insights into a difficult case of homogeneous catalysis
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Carbonylation of epoxides with a combination of Lewis acids and cobalt carbonyls was studied by both theoretical and experimental methods. Only multisite catalysis opens a low-energy pathway for trans opening of oxirane rings. This ring-opening reaction is not easily achieved with a single-site metal catalyst due to structural and thermodynamic constraints. The overall reaction pathway includes epoxide ring opening, which requires both a Lewis acid and a tetracarbonylcobaltate nucleophile, yielding a cobalt alkyl - alkoxy-Lewis acid moiety. After CO insertion into the Co-Calkyl bond, lactone formation results from a nucleophilic attack of the alkoxy Lewis acid entity on the acylium carbon atom. A theoretical study indicates a marked influence of the Lewis acid on both ring-opening and lactone-formation steps, but not on carbonylation. Strong Lewis acids induce fast ring opening, but slow lactone formation, and visa versa: a good balance of Lewis acidity would give the fastest catalytic cycle as all steps have low barriers. Experimentally, carbonylation of propylene oxide to β-butyrolactone was monitored by online ATR-IR techniques with a mixture of tetracarbonylcobaltate and Lewis acids, namely BF3, Me3Al, Et2Al+ · diglyme, and a combination of Me3Al/dicobaltoctacarbonyl. We found that the last two mixtures are extremely active in lactone formation.
- Molnar, Ferenc,Luinstra, Gerrit A.,Allmendinger, Markus,Rieger, Bernhard
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- Acrylonitrile Derivatives from Epoxide and Carbon Monoxide Reagents
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The present invention is directed to reactor systems and processes for producing acrylonitrile and acrylonitrile derivatives. In preferred embodiments of the present invention, the processes comprise the following steps: introducing an epoxide reagent and carbon monoxide reagent to at least one reaction vessel through at least one feed stream inlet; contacting the epoxide reagent and carbon monoxide reagent with a carbonylation catalyst to produce a beta-lactone intermediate; polymerizing the beta-lactone intermediate with an initiator in the presence of a metal cation to produce a polylactone product; heating the polylactone product under thermolysis conditions to produce an organic acid product; optionally esterifying the organic acid product to produce one or more ester products; and reacting the organic acid product and/or ester product with an ammonia reagent under ammoxidation conditions to produce an acrylonitrile product.
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Paragraph 0194; 0196
(2019/01/15)
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- Ruthenium-Promoted Acceptorless and Oxidant-Free Lactone Synthesis in Aqueous Medium
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Ruthenium-catalyzed formation of lactones from diols in aqueous medium has been demonstrated. 1,3,5-Triazaphosphaadamantane (PTA) included water-soluble ruthenium complexes [RuCl 2 (PPh 3)(2,6-Py-(CH 2 -PTA) 2 ]·2Br and [RuCl 2 (PPh 3) 2 (2-PyCH 2 PTA)]·Br in the presence of KOH were found to be efficient for the synthesis of lactones from diols. The reported synthetic protocol is green as it uses water as solvent, avoids the use of any hydrogen acceptor/oxidant, and produces hydrogen as the only side product. Mechanistic studies revealed that lactone formation involved aldehyde intermediate and followed dehydrogenative pathway.
- Bhatia, Anita,Kannan, Muthukumar,Muthaiah, Senthilkumar
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supporting information
p. 721 - 725
(2019/03/26)
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- PROCESSES FOR PRODUCING BETA-LACTONE AND BETA-LACTONE DERIVATIVES WITH HETEROGENOUS CATALYSTS
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The present invention is directed to processes from producing beta-lactone and beta-lactone derivatives using heterogenous catalysts. In preferred embodiments of the present invention, the processes comprise the steps: passing a feed stream comprising an epoxide reagent and a carbon monoxide reagent to a reaction zone; contacting the epoxide reagent and the carbon monoxide reagent with a heterogenous catalyst to produce a beta-lactone product in the reaction zone; and removing the beta-lactone product from the reaction zone. In preferred embodiments, the heterogenous catalyst comprises a solid support containing a cationic Lewis acid functional group and a metal carbonyl compound comprising at least one of anionic metal carbonyl compound or a neutral metal carbonyl compound. In certain preferred embodiments, the epoxide reagent and carbon monoxide reagent have a biobased content.
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Paragraph 0185-0192
(2019/02/24)
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- Molecular products from the thermal degradation of glutamic acid
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The thermal behavior of glutamic acid was investigated in N2 and 4% O2 in N2 under flow reactor conditions at a constant residence time of 0.2 s, within a total pyrolysis time of 3 min at 1 atm. The identification of the main pyrolysis products has been reported. Accordingly, the principal products for pyrolysis in order of decreasing abundance were succinimide, pyrrole, acetonitrile, and 2-pyrrolidone. For oxidative pyrolysis, the main products were succinimide, propiolactone, ethanol, and hydrogen cyanide. Whereas benzene, toluene, and a few low molecular weight hydrocarbons (propene, propane, 1-butene, and 2-butene) were detected during pyrolysis, no polycyclic aromatic hydrocarbons (PAHs) were detected. Oxidative pyrolysis yielded low molecular weight hydrocarbon products in trace amounts. The mechanistic channels describing the formation of the major product succinimide have been explored. The detection of succinimide (major product) and maleimide (minor product) from the thermal decomposition of glutamic acid has been reported for the first time in this study. Toxicological implications of some reaction products (HCN, acetonitrile, and acyrolnitrile), which are believed to form during heat treatment of food, tobacco burning, and drug processing, have been discussed in relation to the thermal degradation of glutamic acid.
- Kibet, Joshua K.,Khachatryan, Lavrent,Dellinger, Barry
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p. 7696 - 7704
(2013/09/02)
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- PROCESS FOR THE PRODUCTION OF ACID ANHYDRIDES FROM EPOXIDES
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A method of making acid anhydrides from epoxide and carbon monoxide feedstocks is presented. In various aspects, the method includes steps of reacting the contents of a feed stream comprising an epoxide, a solvent, a carbonylation catalyst and carbon monoxide to produce a first carbonylation product stream comprising a beta-lactone, then reacting the contents of the first carbonylation product stream with additional carbon monoxide to produce a second carbonylation product stream comprising an acid anhydride, and separating at least a portion of the acid anhydride from the second carbonylation product stream to produce: i) an acid anhydride product stream comprising the separated portion of acid anhydride; and ii) a recycling stream comprising the carbonylation catalyst, and finally adding the recycling stream to the feed stream.
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Page/Page column 50-51
(2013/08/28)
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- ACRYLIC ACID PRODUCTION METHODS
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In one aspect, the present invention encompasses safe and efficient methods for providing highly pure acrylic acid. In certain embodiments, the inventive methods include the step of producing polypropiolactone from ethylene oxide at a first location, transporting the polymer to a second location and pyrolyzing the polypropiolactone to provide glacial acrylic acid. In certain embodiments, the step of pyrolyzing the polymer is performed continuously in conjunction with a polymerization process to make SAPs.
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Page/Page column 12; 13; 14
(2013/09/12)
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- PROCESS FOR BETA-LACTONE PRODUCTION
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The present application provides a method for producing an beta-lactone product. The method includes the steps of: reacting an epoxide, a solvent with a carbonylation catalyst and carbon monoxide to produce a reaction stream comprising a beta-lactone then separating a portion of the beta-lactone in the reaction stream from the solvent and carbonylation catalyst to produce: i) a beta-lactone stream with the beta-lactone, and ii) a catalyst recycling stream including the carbonylation catalyst and the high boiling solvent; and adding the catalyst recycling stream to the feed stream.
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Page/Page column 15
(2012/05/21)
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- CARBONYLATION OF EPOXIDES
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The present invention pertains to a process for the carbonylation of an epoxide by reacting it with carbon monoxide in the presence of a catalyst system containing two components, wherein the first component is a source of one or more metals selected from the group consisting of cobalt, ruthenium and rhodium, and the second component is a coordination complex of a tetrapyrrole compound with one or more of the metals belonging to the group consisting of groups IIIA and IIIB of the periodic system, lanthanides and actinides. The present invention also pertains a process for the preparation of catalyst system, and to the use of such catalyst system for the carbonylation of epoxides.
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- Generation of alkyl hypochlorites in oxidation of alcohols with carbon tetrachloride catalyzed by vanadium and manganese compounds
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Primary alcohols and diols with various structures were subjected to transformations into esters, aldehydes, ketones, and lactones under the action of carbon tetrachloride in the presence of manganese compounds (MnCl 2, MnO2, Mn(OAc)2, Mn(acac)3) and vanadium compounds (VCl5, V2O5, VO(acac) 2) as catalysts. These transformation proceeded with the involvement of alkyl hypochlorites, which were generated in the course of oxidation of alcohols with carbon tetrachloride catalyzed by manganese or vanadium compounds. The optimum molar ratios between the catalyst and reagents were determined, and the reaction conditions for the highly selective synthesis of esters, aldehydes, ketones, and lactones from alcohols were found.
- Khusnutdinov,Shchadneva,Baiguzina,Lavrentieva,Dzhemilev
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p. 2074 - 2079
(2007/10/03)
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- Amino acid nitrosation products as alkylating agents
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Nitrosation reactions of α-, β-, and γ-amino acids whose reaction products can act as alkylating agents of DNA were investigated. To approach in vivo conditions for the two-step mechanism (nitrosation and alkylation), nitrosation reactions were carried ou
- Garcia-Santos,Calle,Casado
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p. 7506 - 7510
(2007/10/03)
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- Synthesis of β-lactones by the regioselective, cobalt and Lewis acid catalyzed carbonylation of simple and functionalized epoxides
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The PPNCo(CO)4 and BF3·Et2O catalyzed carbonylation of simple and functionalized epoxides in DME gives the corresponding β-lactones regioselectively in good to high yields. The carbonylation occurred selectively at the uns
- Lee, Jong Tae,Thomas,Alper
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p. 5424 - 5426
(2007/10/03)
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- Nickel (II) and iron (II) / Dowex 50W: An effective catalyst for the Baeyer-Villiger oxidation of ketones using molecular oxygen and benzaldehyde
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A mixture of Ni(II) and Fe(II) supported on Dowex 50W catalyses Baeyer- Villiger oxidation of ketones using molecular oxygen and benzaldehyde.
- Hashemi,Beni
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p. 196 - 197
(2007/10/03)
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- Method for synthesizing oxetan-2-ones and intermediates for their preparation
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A method is described for the synthesis of oxetan-2-ones comprising protection of the hydroxy group of an hydroxy ester with an acid-labile acetal protecting group, reduction of this O-protected hydroxy ester to an O-protected hydroxy aldehyde, condensation of this aldehyde with a metal enolate of an activated carboxylic acid derivative and spontaneous deprotection of the hydroxy group during the acidic workup procedure. Using the new O-protected hydroxy aldehydes as intermediates the oxetan-2-ones can be obtained after separation in diastereomerically and enantiomerically pure form, in a remarkably reduced number of steps, and in a significantly improved overall yield.
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- P(CH3NCH2CH2)3N: A Nonionic Superbase for Efficient Dehydrohalogenation
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The commercially available nonionic Superbase P(CH3NH2CH2)3N (1) is far superior to DBU for the conversion of primary and secondary alkyl halides to alkenes. A reason for the efficacy of acetonitrile as a solvent for the halides requiring extended reaction times is presented.
- Arumugam, Subramaniam,Verkade, John G.
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p. 4827 - 4828
(2007/10/03)
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- DISTRIBUTION OF β-LACTONES BETWEEN AQUEOUS AND ORGANIC PHASES
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Distribution coefficients of β-lactones between aqueous and organic phases are determined by the electrophilicity of the organic extractant, but a satisfactory quantitative relation between the distribution coefficients and the properties of organic solvents can be obtained only by a multiparameter equation that takes various solvation processes into account.The distribution of β-lactones between aqueous and organic phases can be described by the equation (corg)n/(cH2O) = const.
- Kotovich, Kh. Z.,Makitra, R. G.,Pirig, Ya. N.,Khorunzha, Ya. M.
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p. 445 - 451
(2007/10/02)
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- RING-CLOSURE REACTIONS. XXV. WHY ARE STRAINED SMALL RINGS SO EASILY FORMED IN INTRAMOLECULAR NUCLEOPHILIC SUBSTITUTION REACTIONS?
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The leaving group effect (kBr/kCl) has been determined for two typical series of SN2 cyclisation reactions in the ring size range of 3 to 6 in order to probe the effect of ring strain on transition state structure.The general increase of the magnitude of the leaving group effect on going from the less strained to the more strained ring systems indicates that bond making and bond breaking is significant also in the small ring transition states.The apparent unimportance of strain in the products to the ease of closure of the smallest rings is tentatively explained by the hypothesis that the adverse effect of ring strain is partially offset by a significant reduction of non-bonded interactions in the transition states.
- Casadei, Maria Antonietta,Martino, Alessandro di,Galli, Carlo,Mandolini, Luigi
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p. 659 - 664
(2007/10/02)
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- Macrocyclic Oligolactones by Oligomerization of Simple Lactones
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The catalyst system K-t-butoxide/THF is useful not only for converting ε-caprolactone into the known cyclic oligomers (14-, 21-, 28-ring etc.) but also for preparing the unknown cyclic oligomers of δ-valerolactone (12-, 18-, 24-ring etc.) if large amounts of catalyst are used in the presence of t-butyl alcohol.With γ-butyrolactone, the acidity of the α-CH2 leads instead to a bicyclic aldol type condensation product for which there is evidence of subsequent dimerization to a tricyclic 10-ring dilactone. β-Propiolactone undergoes eliminative ring-opening to acrylic acid which is in equilibrium with acyclic homologues.In contrast, the catalyst system BF3/CH2Cl2 converts β-propiolactone (but not the other lactones) cleanly to cyclic oligomers (12-, 16-, 20-ring etc.).The driving force for these reactions is primarily the instability of the cis ester configuration in monolactones, the ester groups of the oligolactones adopting exclusively the trans ester configuration.Ring strain seems to contribute only in the case of β-propiolactone.
- Dale, Johannes,Schwartz, Jan-Erik
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p. 559 - 567
(2007/10/02)
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