762-75-4Relevant articles and documents
Sonolytic destruction of methyl tert-butyl ether by ultrasonic irradiation: The role of O3, H2O2, frequency, and power density
Kang, Joon-Wun,Hung, Hui-Ming,Lin, Angela,Hoffmann, Michael R.
, p. 3199 - 3205 (1999)
The kinetics of degradation of methyl tert-butyl ether (MTBE) by ultrasonic irradiation in the presence of ozone as functions of applied frequencies and applied power are investigated. Experiments are performed over the frequency range of 205-1078 kHz. The higher overall reaction rates are observed at 358 and 618 kHz and then at 205 and 1078 kHz. The observed pseudo-first-order rate constant, k(O), for MTBE degradation increases with increasing power density up to 250 W L-1. A linear dependence of the first- order rate constant, k(O3), for the simultaneous degradation of O3 on power density is also observed. Naturally occurring organic matter (NOM) is shown to have a negligible effect on observed reaction rates. The kinetics of degradation of methyl tert-butyl ether (MTBE) by ultrasonic irradiation in the presence of ozone as functions of applied frequencies and applied power are investigated. Experiments are performed over the frequency range of 205-1078 kHz. The higher overall reaction rates are observed at 358 and 618 kHz and then at 205 and 1078 kHz. The observed pseudo-first-order rate constant, k0, for MTBE degradation increases with increasing power density up to 250 W L-1. A linear dependence of the first-order rate constant, kO(3), for the simultaneous degradation of O3 on power density is also observed. Naturally occurring organic matter (NOM) is shown to have a negligible effect on observed reaction rates.
IRON-CATALYZED CROSS-COUPLING OF METHHANOL WITH SECONDARY OR TERTIARY ALCOHOLS TO PRODUCE FORMATE ESTERS
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Paragraph 0124-0126; 0128, (2019/02/17)
A process for preparing a variety of secondary and tertiary alkyl formate esters via the coupling of methanol and secondary (or tertiary) alcohols. Iron-based catalysts, supported by pincer ligands, are employed to produce these formate esters in high yields and unprecedentedly high selectivities (>99%). Remarkably, the coupling strategy is also applicable to bulkier tertiary alcohols, which afford corresponding tertiary formate esters in moderately high yields and high selectivities.
PROCESS FOR MAKING FORMIC ACID UTILIZING LOWER-BOILING FORMATE ESTERS
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Paragraph 00177; 00178, (2019/02/15)
Disclosed is a process for recovering formic acid from a formate ester of a C3 to C4 alcohol. Disclosed is also a process for producing formic acid by carbonylating a C3 to C4 alcohol, hydrolyzing the formate ester of the alcohol, and recovering a formic acid product. The alcohol may be dried and returned to the reactor. The process enables a more energy efficient production of formic acid than the carbonylation of methanol to produce methyl formate.
Purified mCPBA, a Useful Reagent for the Oxidation of Aldehydes
Horn, Alexander,Kazmaier, Uli
, p. 2531 - 2536 (2018/03/21)
Purified mCPBA is a useful reagent for the oxidation of several classes of aldehyde. Although linear unbranched aliphatic aldehydes are oxidized to the corresponding carboxylic acids, α-branched ones undergo Baeyer–Villiger oxidation to formates. α-Branched α,β-unsaturated aldehydes provide enolformates and/or epoxides, which can be saponified to α-hydroxy ketones with shortening of the carbon chain by 1 carbon. Unbranched α,β-unsaturated aldehydes undergo an interesting Baeyer–Villiger oxidation/epoxidation/formate migration/BV oxidation cascade, which results in formyl-protected hydrates with an overall loss of two carbon atoms.
Tailor-made Molecular Cobalt Catalyst System for the Selective Transformation of Carbon Dioxide to Dialkoxymethane Ethers
Schieweck, Benjamin G.,Klankermayer, Jürgen
supporting information, p. 10854 - 10857 (2017/08/30)
Herein a non-precious transition-metal catalyst system for the selective synthesis of dialkoxymethane ethers from carbon dioxide and molecular hydrogen is presented. The development of a tailored catalyst system based on cobalt salts in combination with selected Triphos ligands and acidic co-catalysts enabled a synthetic pathway, avoiding the oxidation of methanol to attain the formaldehyde level of the central CH2 unit. This unprecedented productivity based on the molecular cobalt catalyst is the first example of a non-precious transition-metal system for this transformation utilizing renewable carbon dioxide sources.
TiCl4/Et3N-Mediated Condensation of Acetate and Formate Esters: Direct Access to β-Alkoxy- and β-Aryloxyacrylates
álvarez-Calero, José María,Jorge, Zacarías D.,Massanet, Guillermo M.
supporting information, p. 6344 - 6347 (2016/12/23)
A methodology to build (E)-β-alkoxy- and (E)-β-aryloxyacrylate moieties from acetate and formate esters promoted by the TiCl4/Et3N system is presented. The reaction is compatible with a broad range of structural skeletons and elapses through an unusual condensation pathway. Taking into account the obtained results, we propose a plausible mechanism involving a bimetallic titanium intermediate for this type of transformation.
Double-modified mesoporous molecular sieve catalytic SBA method for preparing carboxylic acid T-butyl ester
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Paragraph 0040; 0041, (2016/11/21)
The invention discloses a method for preparing tert-butyl carboxylate by using a dual-modified SBA mesoporous molecular sieve catalyst. According to the method, carboxylic acid and isobutylene are subjected to addition esterification by using a dual-modified SBA mesoporous molecular sieve as a catalyst to synthesize the tert-butyl carboxylate. The molecular sieve catalyst is a metal-doped sulfonate-grafted dual-modified SBA mesoporous molecular sieve catalyst prepared by a one-step cocondensation process. When the dual-modified SBA mesoporous molecular sieve catalyst is used in the addition esterification reaction process of synthesizing tert-butyl carboxylic acid from carboxylic acid and isobutylene, no polar solvent (such as tert-butyl alcohol, methyl tert-butyl ether or the like) is needed as an isobutylene polymerization inhibitor, and the quantity of the carboxylic acid is not excessive, thereby reducing the energy consumption for separating the reaction product. The catalyst has the advantages of high conversion rate, high selectivity, non-homogeneous phase, no corrosiveness, adjustable acid quantity and acid center and the like, and is recyclable.
Nucleophilic reactivity of a copper(II)-superoxide complex
Pirovano, Paolo,Magherusan, Adriana M.,McGlynn, Ciara,Ure, Andrew,Lynes, Amy,McDonald, Aidan R.
supporting information, p. 5946 - 5950 (2014/06/10)
Metal-bound superoxide intermediates are often implicated as electrophilic oxidants in dioxygen-activating metalloenzymes. In the nonheme iron α-ketoglutarate dependent oxygenases and pterin-dependent hydroxylases, however, FeIII-superoxide intermediates are postulated to react by nucleophilic attack on electrophilic carbon atoms. By reacting a Cu II-superoxide complex (1) with acyl chloride substrates, we have found that a metal-superoxide complex can be a very reactive nucleophile. Furthermore, 1 was found to be an efficient nucleophilic deformylating reagent, capable of Baeyer-Villiger oxidation of a number of aldehyde substrates. The observed nucleophilic chemistry represents a new domain for metal-superoxide reactivity. Our observations provide support for the postulated role of metal-superoxide intermediates in nonheme iron α-ketoglutarate dependent and pterin-dependent enzymes. Nucleophilic superoxide: A copper(II)-superoxide complex has been found to be a highly reactive nucleophile. The complex reacts readily with certain electrophiles and is capable of the nucleophilic deformylation of electron-rich aldehydes (Baeyer-Villiger oxidation). These observations provide experimental support for the postulated nucleophilic reactivity of metal-superoxide intermediates in the catalytic cycles of certain nonheme iron enzymes.
Comparison of photocatalytic performance of degussa TiO2 P25 and P90 in gas phase photocatalytic reactor
In, Su Il
experimental part, p. 2629 - 2631 (2012/01/19)
Photocatalytic performances of Degussa TiO2 P25, one of the most active commercial photocatalysts and P90, recently developed material by Degussa, were studied using gas phase photocatalytic reactor. Photodecomposition of methyl tert-butyl ether was used to characterize photocatalytic behaviour of two samples containing different ratio of TiO2 anatase and rutile. This is the first demonstration that although the activity of P90 was higher than that of P25 TiO2, the surface area normalized activity showed that P25 had a better performance.
Formylation of amines and alcohols using aminopropylated mesoporous SBA-15 silica (APMS) as an efficient and recyclable catalyst
Malakooti, Reihaneh,Sobhani, Sara,Razavi, Nasrin,Shafiei, Soheila,Mokhtari, Rezvan
experimental part, p. 1979 - 1990 (2012/04/17)
Aminopropylated mesoporous SBA-15 silica (APMS) is introduced as a new, recyclable and efficient catalyst for the formylation of a variety of amines and alcohols by using readily available formic acid under solvent-free conditions.
