2144-41-4Relevant academic research and scientific papers
One-pot reduction of 5-hydroxymethylfurfural via hydrogen transfer from supercritical methanol
Hansen, Thomas S.,Barta, Katalin,Anastas, Paul T.,Ford, Peter C.,Riisager, Anders
, p. 2457 - 2461 (2012)
Catalytic conversion of HMF to valuable chemicals was achieved over a Cu-doped porous metal oxide in supercritical methanol. The hydrotalcite catalyst precursor is prepared following simple synthetic procedures, using inexpensive and earth-abundant starting materials in aqueous solutions. The hydrogen equivalents needed for the reductive deoxygenation of HMF originate from the solvent itself upon its reforming. Dimethylfuran, dimethyltetrahydrofuran and 2-hexanol were obtained in good yields. At milder reaction temperatures, a combined yield (DMF + DMTHF) of 58% was achieved. Notably, the formation of higher boiling side products and undesired char from HMF is not detected under these reaction conditions.
Renewable fuels from biomass-derived compounds: Ru-containing hydrotalcites as catalysts for conversion of HMF to 2,5-dimethylfuran
Nagpure, Atul S.,Venugopal, Ashok Kumar,Lucas, Nishita,Manikandan, Marimuthu,Thirumalaiswamy, Raja,Chilukuri, Satyanarayana
, p. 1463 - 1472 (2015)
Production of transportation fuels from renewable biomass is hugely important considering the current ecological concerns over CO2 built up in the atmosphere. Ruthenium-containing hydrotalcite (HT) catalysts were applied for the selective hydrogenolysis of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF). Structural and morphological features of the catalysts were examined using various physico-chemical characterization techniques. The influence of various reaction parameters, such as reaction temperature, solvent, Ru content of the catalyst, etc., was investigated with respect to HMF conversion and DMF yield. The study clearly shows that well-dispersed Ru nanoparticles are highly active and selective in the conversion of HMF to DMF. A catalyst containing only 0.56 wt% Ru converted 100 mol% HMF to yield 58 mol% DMF. This catalyst was found to be recyclable as the activity was retained even after five cycles of reaction. 2-Propanol was found to be a good solvent as it helped to improve DMF yield through transfer hydrogenation. Based on the results of the investigations, a reaction pathway for the conversion of HMF to DMF was proposed for the present Ru-based catalyst system.
(OTf)2 as a homogeneous catalyst for the hydrogenation of biomass derived 2,5-hexanedione and 2,5-dimethyl-furan in aqueous acidic medium
Latifi, Elnaz,Marchese, Austin D.,Hulls, Margaret C.W.,Soldatov, Dmitriy V.,Schlaf, Marcel
, p. 4666 - 4679 (2017/10/13)
The complex [Ru(triphos)(CH3CN)3](OTf)2 is an effective catalyst for the hydrogenation of 2,5-hexanedione and 2,5-dimethyl-furan in aqueous acidic medium at temperatures between 150 and 200 °C realizing up to 96% combined yields of 2,5-hexanediol and 2,5-dimethyl-tetrahydrofuran with the product distribution being sensitive to the amount of acid co-catalyst (HOTf) present. For the furan, the reaction pathway is through an acid-catalyzed hydrolysis to the dione rather than direct hydrogenation of the ring. The hydrogenation of the dione shows a first order dependence on hydrogen pressure as determined by direct hydrogen uptake rate measurements at temperature and pressure (1.38-6.90 MPa at 150 °C) and is postulated to operate through a heterolytic activation of hydrogen gas by [Ru(H)x(triphos)(Y)y]n+ (Y = solvent, water, counter ion) species formed in situ by loss and hydrogenation of the nitrile ligands. In water the catalyst is deactivated by dimerization to [Ru2(μ-OH)3(triphos)2](OTf).
Catalytic transfer hydrogenation/hydrogenolysis for reductive upgrading of furfural and 5-(hydroxymethyl)furfural
Scholz, David,Aellig, Christof,Hermans, Ive
, p. 268 - 275 (2014/03/21)
The sequential transfer hydrogenation/hydrogenolysis of furfural and 5-hydroxymethylfurfural to 2-methylfuran and 2,5-dimethylfuran was studied over in situ reduced, Fe2O3-supported Cu, Ni, and Pd catalysts, with 2-propanol as hydrogen donor. The remarkable activity of Pd/Fe 2O3 in both transfer hydrogenation/hydrogenolysis is attributed to a strong metal-support interaction. Selectivity towards hydrogenation, hydrogenolysis, decarbonylation, and ring-hydrogenation products is shown to strongly depend on the Pd loading. A significant enhancement in yield to 62%, of 2-methylfuran and 2-methyltetrahydrofuran was observed under continuous flow conditions.
Cyclization of alkanediols in high-temperature liquid water with high-pressure carbon dioxide
Yamaguchi, Aritomo,Hiyoshi, Norihito,Sato, Osamu,Shirai, Masayuki
experimental part, p. 302 - 305 (2012/07/28)
Dehydration of 1,4-butanediol (1,4-BDO) to tetrahydrofuran (THF), 2R,5R-hexanediol (2R,5R-HDO) to 2,5-dimethyltetrahydrofuran (2,5-DMTHF), and 2,5-dimethyl-2,5-hexanediol (2,5-DM-2,5-HDO) to 2,2,5,5- tetramethyltetrahydrofuran (2,2,5,5-TMTHF) proceeded in high-temperature liquid water at 523 K. The formation rates of cyclic ethers were enhanced by high-pressure carbon dioxide (16.2 MPa). The order of dehydration rates in high-temperature water with carbon dioxide was 2,5-DM-2,5-HDO > 2R,5R-HDO > 1,4-BDO (tertiary > secondary > primary alcohols), which was the same order as the stability of corresponding carbocation species.
STEREOSELECTIVE SYNTHESIS OF CYCLIC ETHERS VIA BROMINE ASSISTED EPOXIDE RING EXPANSION
Davies, Stephen G.,Polywka, Mario E. C.,Thomas, Susan E.
, p. 1461 - 1464 (2007/10/02)
9-Oxabicyclonon-4-ene reacts with bromine to give stereoselectively trans,trans-2,6-dibromo-9-oxabicyclononane and trans,trans-2,5-dibromo-9-oxabicyclononane.
The photolysis of tetrahydrofuran and of some of its methyl derivatives at 185 nm
Kizilkilic, Nuray,Schuchmann, Heinz-Peter,Sonntag, Clemens Von
, p. 2819 - 2826 (2007/10/02)
The uv photolysis of tetrahydrofuran, 1, 2-methyltetrahydrofuran, 2, cis-2,5-dimethylterahydrofuran, 3, trans-2,5-dimethyltetrahydrofuran, 4, and 2,2,5,5-tetramethyltetrahydrofuran, 5, has been investigated by product analysis in the liquid phase, and quantum yields have been determined.The photolysis of tetrahydrofuran itself was also studied in the gas phase at pressures ranging from 1 to 120 atm (pressurizing gas N2); and very little difference was found between the photolytic behaviour of the vapour at 120 atm and that of the liquid.The major products are in all cases the cyclopropanes and the corresponding carbonyl compounds, as well as the olefinic alcohols and the carbonyl compounds that are isomeric with the starting material.These products are considered to be formed by the two primary processes and . The cyclopropanes formed in reaction retain some excess energy (apparently more then is needed to realize the trimethylene form), and in the photolysis of tetrahydrofuran vaapour the hot cyclopropane rearranges to a considerable extent into propene.The propene to cyclopropane yield ratio falls strongly with increasing pressure, to a value of 0.065 at 120 atm.A similar value is observed in the liquid phase photolysis.The five-membered oxyl alkyl diradical from reaction is the likely intermediate in the cis-trans photoisomerization that is observable with the 2,5-dimethyltetrahydrofurans (Φ(cis -> trans) ca. Φ(trans -> cis) ca. 0.2).The photolysis of these compounds also demonstrates that steric factors have a strong bearing on the course of the reaction, e. g. the quantum yield of methylcyclopropane from the cis compound is 0.22, vs. 0.08 from the trans compound.Molecular hydrogen is produced if the tetrahydrofurans carry hydrogen in α-position.Its production is enhanced if the α-position is shared with a methyl group (1 gives a hydrogen quantum yield of 0.07, 2 of 0.17, 3 of 0.27, 4 of 0.29, and 5 of zero).
