929-61-3Relevant articles and documents
Bifunctional nanoparticle-SILP catalysts (NPs@SILP) for the selective deoxygenation of biomass substrates
Luska, Kylie L.,Julis, Jennifer,Stavitski, Eli,Zakharov, Dmitri N.,Adams, Alina,Leitner, Walter
supporting information, p. 4895 - 4905 (2015/02/19)
Ruthenium nanoparticles were immobilized onto an acidic supported ionic liquid phase (RuNPs@SILP) in the development of bifunctional catalysts for the selective deoxygenation of biomass substrates. RuNPs@SILPs possessed high catalytic activities, selectivities and recyclabilities in the hydrogenolytic deoxygenation and ring opening of C8- and C9-substrates derived from furfural or 5-hydroxymethylfurfural and acetone. Tailoring the acidity of the SILP through the ionic liquid loading provided a molecular parameter by which the catalytic activity and selectivity of the RuNPs@SILPs were controlled to provide a flexible catalyst system toward the formation of different classes of value-added products: cyclic ethers, primary alcohols or aliphatic ethers. This journal is
One-step chemoselective conversion of tetrahydropyranyl ethers to silyl-protected alcohols
Bergueiro, Julian,Montenegro, Javier,Saa, Carlos,Lopez, Susana
, p. 14475 - 14479 (2014/04/17)
Aluminium trichloride catalyses the expeditious direct conversion of tetrahydropyranyl ethers to silyl ethers. This one-step transformation is chemoselective versus deprotection of the acetal and hydrosilylation of unsaturated carbon-carbon bonds, and can also be applied to linear acetals. A possible mechanism is tentatively proposed. This journal is the Partner Organisations 2014.
Influence of the functionalization degree of acidic ion-exchange resins on ethyl octyl ether formation
Guilera, Jordi,Hanková, Libuse,Jerabek, Karel,Ramírez, Eliana,Tejero, Javier
, p. 14 - 22 (2014/04/03)
Ethyl octyl ether (EOE) can be obtained by the ethylation of 1-octanol by means of ethanol or diethyl carbonate over acidic ion-exchange resins. However, EOE formation has to compete with the less steric demanding formation of diethyl ether, by-product obtained from ethanol dehydration or diethyl carbonate decomposition. In the present work, the influence of the resin functionalization degree on EOE formation has been evaluated. A series of partially sulfonated resins (0.87-4.31 mmol H+/g) were prepared by the sulfonation of a macroreticular styrene-divinylbenzene copolymer. The catalysts were characterized, and subsequently, tested in a batch reactor (T = 150 C, P = 25 bar). Amberlyst 15 and 46 were also tested for comparison purposes. Catalytic runs revealed that EOE formation occurred mainly in the firstly sulfonated domain of the polymer skeleton, the least crosslinked; while diethyl ether was formed in the whole polymer bead. Accordingly, the functionalization of the least accessible polymer domain, as a result of increasing the sulfonation temperature or by using a pre-swelling solvent, is not suitable to produce long chain ethers such as EOE; which are preferred as diesel fuels.
Thermal stability and water effect on ion-exchange resins in ethyl octyl ether production at high temperature
Guilera, Jordi,Ramírez, Eliana,Fité, Carles,Iborra, Montserrat,Tejero, Javier
, p. 301 - 309 (2013/09/02)
Abstract Thermal stability and water inhibition effects were studied at 150 and 190 C on the chlorinated acidic polystyrene-divinylbenzene resins Amberlyst 70, Amberlyst XE804 and Purolite CT482, and the non-chlorinated one Dowex 50Wx2. Catalytic activity in the reaction between ethanol and 1-octanol to form ethyl octyl ether (EOE) was monitored for 70 h in a continuous fixed-bed reactor. Leaching of sulfonic groups at 190 C was found to be negligible for Purolite CT482 and Amberlyst 70, but it was significant for Amberlyst XE804 and Dowex 50Wx2. The activity decay to a steady EOE reaction rate on Purolite CT482 and Amberlyst 70 has been ascribed to the reaction rate inhibition by the formed water. However, water adsorption on the catalyst also modified the resin morphology during the course of the reaction. Adsorbed water swelled the gel-phase and more acid sites became accessible for 1-octanol molecules. As a result, the activity decay of EOE and the longer byproduct di-n-octyl ether syntheses was smaller than that of the shorter one diethyl ether.
Mild and efficient capture and functionalisation of CO2 using silver(i) oxide and application to 13C-labelled dialkyl carbonates
Tunbridge, Gemma A.,Baruchello, Riccardo,Caggiano, Lorenzo
, p. 4613 - 4621 (2013/05/08)
A high yielding three-component reaction between β-iodo ethylamine derivatives, MeOH and gaseous CO2 at ambient temperatures and pressures is reported using silver(i) oxide. Unfunctionalised alkyl iodides were also found to be effective in this transformation and their optimisation is also described. To highlight the ease and control with which gaseous CO 2 can be captured and functionalised under mild conditions, the reaction was performed using 13C-enriched CO2 to afford specifically 13C-carbonyl-labelled dialkyl carbonates with exquisite control of the isotopic purity in good yields and without the need for specialised equipment.
Synthesis of ethyl octyl ether from diethyl carbonate and 1-octanol over solid catalysts. A screening study
Guilera,Bringué,Ramírez,Iborra,Tejero
body text, p. 21 - 29 (2012/03/27)
The synthesis of ethyl octyl ether (EOE) from a mixture of diethyl carbonate (DEC) and 1-octanol (1:2 molar ratio) over several solid catalysts was studied in batch mode at 150 °C and 25 bar. Catalyst screening revealed that EOE could be successfully obtained over some acid catalysts. In particular the highest yield was achieved over acid ion-exchange resins (33% after 8 h). A reaction scheme of the process is proposed. Selectivity to EOE was mainly affected by the production of diethyl ether (DEE) and di-n-octyl ether (DNOE). However, EOE was the main ether obtained (60 mol%), followed by DEE (20 mol%) and DNOE (20 mol%). By comparing the behavior of several acid resins, it was seen that the synthesis of EOE was highly related to the structural resin properties. It was found that the accessibility of DEC and 1-octanol to acid centers was improved over highly swollen and low polymer density resins. Thus, gel-type resins with low divinylbenzene content are the most suitable to produce EOE (e.g., Amberlyst 121, Dowex 50Wx2-100 and CT224).
Correlation of the rates of solvolysis of n-octyl fluoroformate and a comparison with n-octyl chloroformate solvolysis
Kevill, Dennis N.,D'Souza, Malcolm J.
, p. 240 - 243 (2007/10/03)
The specific rates of solvolysis of n-octyl fluoroformate have been measured at 24.2°C in 28 pure and binary solvents. For the 23 solvents for which both NT(solvent nucleophilicity) and YCl (solvent ionizing power) values are known, a correlation using the two-term Grunwald-Winstein equation leads to sensitivities towards changes in the two scales of 1.80 ± 0.13 (l value) and 0.79 ± 0.06 (m value), respectively. For seven solvents, a parallel study was made of n-octyl chloroformate solvolysis and F:Cl specific rate ratios were, in most instances, above unity, consistent with the association step of an association-dissociation (addition-elimination) pathway being rate-determining.
Azole derivative with leukotriene (LTs) antagonizing activity and thromboxane (TX) A2 antagonizing activity
-
, (2008/06/13)
An azole derivative represented by general formula (I) or a pharmaceutically acceptable salt thereof, having both of a leukotriene antagonistic effect and a thromboxane A2 antagonistic effect and being useful in preventing or treating allergic diseases, ischemic heart diseases or ischemic brain diseases, and a medicinal composition containing the same as the active ingredient, wherein R1 and R2 may be the same or different and represent each hydrogen, cycloalkyl, etc., or R1 and R2 together with (a) may form a fused ring (b) or (c) which may be substituted by optionally substituted lower alkyl, amino, etc.; R3, R6, R7, R8 may be the same or different and represent each hydrogen, amino, etc.; R4 represents cyano, tetrazolyl, --COOR9, etc.; R5 represents hydrogen or lower alkyl; D represents optionally substituted lower alkylene; X and Z may be the same or different and represent each oxygen or sulfur; Y represents --N= or --CH=; A represents --O--B--, --B--O--, --S--B--, --B--S-- or --B-- (B being lower alkylene or lower alkenylene); and n is 0, 1, or 2.
Carbonylation of alkyl sulfonates catalyzed by cobalt complexes
Urata, Hisao,Goto, Daisuke,Fuchikami, Takamasa
, p. 3091 - 3094 (2007/10/02)
Alkyl sulfonates (R1-OSO2R2) react with carbon monoxide and alcohol (R3-OH) in the presence of catalytic amounts of Co complex and Nal to afford the corresponding esters (R1-COOR3) in moderate to good yields.
