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1003-38-9 Usage

Chemical Properties

clear colorless liquid

Uses

2,5-Dimethyltetrahydrofuran is used in preparation method for Hydrodeoxygenation of Oxygenated compounds to unsaturaded products.

Synthesis Reference(s)

Journal of the American Chemical Society, 72, p. 1593, 1950 DOI: 10.1021/ja01160a045

Check Digit Verification of cas no

The CAS Registry Mumber 1003-38-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,0,0 and 3 respectively; the second part has 2 digits, 3 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 1003-38:
(6*1)+(5*0)+(4*0)+(3*3)+(2*3)+(1*8)=29
29 % 10 = 9
So 1003-38-9 is a valid CAS Registry Number.
InChI:InChI=1/C6H12O/c1-5-3-4-6(2)7-5/h5-6H,3-4H2,1-2H3/t5-,6-/m0/s1

1003-38-9 Well-known Company Product Price

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  • Aldrich

  • (D187208)  2,5-Dimethyltetrahydrofuran,mixtureofcisandtrans  96%

  • 1003-38-9

  • D187208-5G

  • 629.46CNY

  • Detail

1003-38-9SDS

SAFETY DATA SHEETS

According to Globally Harmonized System of Classification and Labelling of Chemicals (GHS) - Sixth revised edition

Version: 1.0

Creation Date: Aug 12, 2017

Revision Date: Aug 12, 2017

1.Identification

1.1 GHS Product identifier

Product name 2,5-DIMETHYLTETRAHYDROFURAN

1.2 Other means of identification

Product number -
Other names 2,5-Dimethyloxolane

1.3 Recommended use of the chemical and restrictions on use

Identified uses For industry use only.
Uses advised against no data available

1.4 Supplier's details

1.5 Emergency phone number

Emergency phone number -
Service hours Monday to Friday, 9am-5pm (Standard time zone: UTC/GMT +8 hours).

More Details:1003-38-9 SDS

1003-38-9Relevant articles and documents

One-Step catalytic transformation of carbohydrates and cellulosic biomass to 2,5-dimethyltetrahydrofuran for liquid Fuels

Yang, Weiran,Sen, Ayusman

, p. 597 - 603 (2010)

Existing technologies to produce liquid fuels from biomass are typically energy-intensive, multistep processes. Many of these processes use edible biomass as starting material. Carbohydrates, such as monoand polysaccharides and cellulose, typically constitute 50-80% of plant biomass. Herein, we report that hexose from a wide range of biomass-derived carbohydrates, cellulose, and even raw lignocellulose (e.g., corn stover) can be converted into 2,5-dimethyltetrahydrofuran (DMTHF) in one step, in good yields and under mild conditions in water. Under the same conditions, 2-methyltetrahydrofuran is formed from pentose. The reaction employs a soluble rhodium catalyst, dihydrogen, and HI/HCl+NaI. The catalytic system is robust and can be recycled repeatedly without loss of activity. DMTHF is superior to ethanol and has many of the desirable properties currently found in typical petroleum-derived transportation fuels.

Selective hydrogenation of 5-ethoxymethylfurfural over alumina-supported heterogeneous catalysts

Ras, Erik-Jan,Maisuls, Sergio,Haesakkers, Paul,Gruter, Gert-Jan,Rothenberg, Gadi

, p. 3175 - 3185 (2009)

We report here the synthesis and testing of a set of 48 alumina-supported catalysts for hydrogenation of 5-ethoxymethylfurfural. This catalytic reaction is very important in the context of converting biomass to biofuels. The catalysts are composed of one

Heterogeneous Ketone Hydrodeoxygenation for the Production of Fuels and Feedstocks from Biomass

Jenkins, Rhodri W.,Moore, Cameron M.,Semelsberger, Troy A.,Sutton, Andrew D.

, p. 2807 - 2815 (2017)

In this work, we describe a simple, heterogeneous catalytic system for the hydrodeoxygenation (HDO) of 5-nonanone and 2,5-hexanedione, which we use as model compounds for more complex biomass-derived molecules. We present the stepwise reduction of ketones by using supported metal and solid acid catalysts to identify the intermediates en route to hydrocarbons. Although monoketone HDO can be achieved rapidly using moderate conditions (Ni/SiO2.Al2O3, HZSM-5, 200 °C, 1.38 MPa H2, 1 h), quantitative γ-polyketone HDO requires higher pressures and longer reaction times (Pd/Al2O3, HZSM-5, 2.76 MPa H2, 5 h), although these are more facile conditions than have been reported previously for γ-polyketone HDO. Stepwise HDO of the γ-polyketone shows the reaction pathway occurs through ring-closure to a saturated tetrahydrofuran species intermediate, which requires increased H2 pressure to ring-open and subsequently to fully HDO. This work allows for further understanding of bio-derived molecule defunctionalization mechanisms, and ultimately aids in the promotion of biomass as a feedstock for fuels and chemicals.

Formic Acid-Assisted Selective Hydrogenolysis of 5-Hydroxymethylfurfural to 2,5-Dimethylfuran over Bifunctional Pd Nanoparticles Supported on N-Doped Mesoporous Carbon

Hu, Bin,Warczinski, Lisa,Li, Xiaoyu,Lu, Mohong,Bitzer, Johannes,Heidelmann, Markus,Eckhard, Till,Fu, Qi,Schulwitz, Jonas,Merko, Mariia,Li, Mingshi,Kleist, Wolfgang,H?ttig, Christof,Muhler, Martin,Peng, Baoxiang

, p. 6807 - 6815 (2021)

Biomass-derived 5-hydroxymethylfurfural (HMF) is regarded as one of the most promising platform chemicals to produce 2,5-dimethylfuran (DMF) as a potential liquid transportation fuel. Pd nanoparticles supported on N-containing and N-free mesoporous carbon materials were prepared, characterized, and applied in the hydrogenolysis of HMF to DMF under mild reaction conditions. Quantitative conversion of HMF to DMF was achieved in the presence of formic acid (FA) and H2 over Pd/NMC within 2 h. The reaction mechanism, especially the multiple roles of FA, was explored through a detailed comparative study by varying hydrogen source, additive, and substrate as well as by applying in situ ATR-IR spectroscopy. The major role of FA is to shift the dominant reaction pathway from the hydrogenation of the aldehyde group to the hydrogenolysis of the hydroxymethyl group via the protonation by FA at the C-OH group, lowering the activation barrier of the C?O bond cleavage and thus significantly enhancing the reaction rate. XPS results and DFT calculations revealed that Pd2+ species interacting with pyridine-like N atoms significantly enhance the selective hydrogenolysis of the C?OH bond in the presence of FA due to their high ability for the activation of FA and the stabilization of H?.

Mechanistic study of a one-step catalytic conversion of fructose to 2,5-dimethyltetrahydrofuran

Grochowski, Matthew R.,Yang, Weiran,Sen, Ayusman

, p. 12363 - 12371 (2012)

Carbohydrates, such as fructose, can be fully dehydroxylated to 2,5-dimethyltetrahydrofuran (DMTHF), a valuable chemical and potential gasoline substitute, by the use of a dual catalytic system consisting of HI and RhX 3 (X=Cl, I). A mechanistic study has been carried out to understand the roles that both acid and metal play in the reaction. HI serves a two-fold purpose: HI acts as a dehydration agent (loss of 3 H2O) in the initial step of the reaction, and as a reducing agent for the conjugated carbinol group in a subsequent step. I2 is formed in the reduction step and metal-catalyzed hydrogenation reforms HI. The rhodium catalyst, in addition to catalyzing the reaction of iodine with hydrogen, functions as a hydrogenation catalyst for C=O and C=C bonds. A general mechanistic scheme for the overall reaction is proposed based on identification of intermediates, independent reactions of the intermediates, and deuterium labeling studies. Copyright

Highly efficient synchronized production of phenol and 2,5-dimethylfuran through a bimetallic Ni-Cu catalyzed dehydrogenation-hydrogenation coupling process without any external hydrogen and oxygen supply

Li, Wei,Fan, Guoli,Yang, Lan,Li, Feng

, p. 4353 - 4363 (2017)

2,5-Dimethylfuran (DMF) and phenol are considered as one of the new-fashioned liquid transportation biofuels and a key motif for industrial chemicals, respectively. Herein, a highly efficient vapor-phase dehydrogenation-hydrogenation coupling process over bimetallic Ni-Cu alloy nanocatalysts was established for the synchronized production of phenol and DMF with unprecedentedly high yields (>97%) from two cyclohexanol (CHL) and biomass-derived 5-hydroxymethylfurfural (HMF) substrates, without any external hydrogen and oxygen supply. Systematic characterization and catalytic experiments revealed that the production of phenol went through a consecutive triple-dehydrogenation process from CHL, while HMF was simultaneously hydrogenated into DMF using active hydrogen species generated from the dehydrogenation process. The bimetallic Ni-Cu alloy nanostructures derived from Ni-Cu-Al layered double hydroxide precursors and strong metal-support interactions play important roles in governing the present coupling process. An appropriate Ni-Cu alloy nanostructure could greatly facilitate the dehydrogenative aromatization of CHL, thus significantly improving the selectivities to both phenol and DMF. Such an unparalleled efficient, eco-friendly and versatile coupling process for the synchronized production of various substituted phenols and DMF makes it practically promising for large-scale industrial applications in terms of green chemistry and sustainable development.

Tailored one-pot production of furan-based fuels from fructose in an ionic liquid biphasic solvent system

Li, Changzhi,Cai, Haile,Zhang, Bo,Li, Weizhen,Pei, Guangxian,Dai, Tao,Wang, Aiqin,Zhang, Tao

, p. 1638 - 1646 (2015)

The one-pot catalytic transformation of biomass to useful products is desirable for saving cost and time. The integration of the various reaction steps need to address the presence of incompatible reaction conditions and numerous side reactions. We report a novel process for the one-pot production of furan-based fuels, 2,5-dimethylfuran (DMF) and 2,5-dihmethyltetrahydrofuran (DMTF), from fructose by optimizing the synergic effect of an ionic liquid promoted Ru/C catalyst and the solvent effect. The dehydration of fructose and subsequent in situ hydrodeoxygenation of HMF to DMF and DMTF on Ru/C were enhanced by the use of an ionic liquid and a biphasic [BMIm]Cl/THF solvent. Elemental analysis, X-ray Photoelectron Spectroscopy, Raman spectroscopy and H2-temperature programmed reduction-mass spectroscopy characterization showed that the ionic liquid modified the electronic density of the Ru species to favor HMF in situ hydrodeoxygenation. Moreover, THF served as a reaction-extraction solvent that extracted DMF and DMTF from the reaction layer to avoid further side reactions. A rational design that gave enhancement of the catalytic performance and product protection provides a promising strategy for the one-pot conversion of biomass to desired fuels.

Ruthenium-8-quinolinethiolate-phenylterpyridine versus ruthenium-bipyridine-phenyl-terpyridine complexes as homogeneous water and high temperature stable hydrogenation catalysts for biomass-derived substrates

Sullivan, Ryan J.,Kim, Jin,Hoyt, Caroline,Silks, Louis A.,Schlaf, Marcel

, p. 104 - 114 (2016)

[(4′-Ph-terpy)(bipy)Ru(L)](OTf)n and [(4′-Ph-terpy)(quS)Ru(L)](OTf)n (n = 0 or 1 depending on the charge of L, L = labile ligand, e.g., H2O, CH3CN or OTf, bipy = 2,2′-bipyridine, quS = quinoline-8-thiolate) have been evaluated as catalysts for the hydrogenation of the biomass-derivable C6-substrates 2,5-dimethylfuran (obtainable from 5-hydroxymethylfurfural) and 2,5-hexanedione (the hydrolysis product of 2,5-dimethylfuran). Operating in aqueous acidic medium at T = 175-225 °C the bipy complex is only marginally active, while the quinoline-8-thiolate complex realizes yields of hydrogenated products up to 97% starting from 2,5-hexanedione and up to 66% starting from 2,5-dimethylfuran. The catalyst can also convert the 5-HMF derived acetone 4-(5-methyl-2-furanyl)-3-buten-2-one into 2,5,8-nonatriol, a potentially valuable cross-linker for polymer formulations. On the basis of DFT calculations, the higher activity of the quinoline-8-thiolate complex is proposed to be rooted in a metal-ligand bifunctional mechanism for the heterolytic activation and transfer of dihydrogen to the carbonyl substrate with the hydride-thiol complex [(4′-Ph-terpy)(quSH)Ru(H)]+ as the active catalyst.

Ni Nanoparticles Inlaid Nickel Phyllosilicate as a Metal-Acid Bifunctional Catalyst for Low-Temperature Hydrogenolysis Reactions

Kong, Xiao,Zhu, Yifeng,Zheng, Hongyan,Li, Xianqing,Zhu, Yulei,Li, Yong-Wang

, p. 5914 - 5920 (2015)

Hydrogenolysis of carbon-oxygen bonds is a versatile synthetic method, of which hydrogenolysis of bioderived 5-hydroxymethylfurfural (HMF) to furanic fuels is especially attractive. However, low-temperature hydrogenolysis (in particular over non-noble catalysts) is challenging. Herein, nickel nanoparticles (NPs) inlaid nickel phyllosilicate (NiSi-PS) are presented for efficient hydrogenolysis of HMF to yield furanic fuels at 130-150 °C, being much superior with impregnated Ni/SiO2 catalysts prepared from the same starting materials. NiSi-PS also shows a 2-fold HMF conversion intrinsic rate and 3-fold hydrogenolysis rate compared with the impregnated Ni/SiO2. The superior performance originated from the synergy of highly dispersed nickel NPs and substantially formed acid sites due to coordinatively unsaturated Ni (II) sites located at the remnant nickel phyllosilicate structure, as revealed by detailed characterizations. The model reactions over the other reference catalysts further highlighted the metal-acid synergy for hydrogenolysis reactions. NiSi-PS can also efficiently catalyze low-temperature hydrogenolysis of bioderived furfural and 5-methylfurfural, demonstrating a great potential for other hydrogenolysis reactions.

A Convenient One-step Preparation of Oxacyclanes by Dehydration of Diols over Alumina

Inoue, Yoshihisa,Deguchi, Shokichiro,Hakushi, Tadao

, p. 3031 - 3032 (1980)

Dehydration of 1,4-, 1,5-, or 1,6- alkanediols over alumina at 220-250 deg C in a distillation apparatus gave the corresponding 5- to 7-membered oxacyclanes in good yield of 51-71percent.Diethylene glycol also gave 1,4-dioxane in 49percent yield, whereas attempted one-step synthesis of crown ethers from polyethylene glycols in a similar manner resulted in the predominant formation of 1,4-dioxane without any trace of crown ether.

Direct use of humic acid mixtures to construct efficient Zr-containing catalysts for Meerwein-Ponndorf-Verley reactions

Sha, Yufei,Xiao, Zhenhuan,Zhou, Huacong,Yang, Keli,Song, Yinmin,Li, Na,He, Runxia,Zhi, Keduan,Liu, Quansheng

, p. 4829 - 4837 (2017)

With the increasing demands for energy and carbon resources, exploration of novel utilization approaches of fossil resources and promotion of the conversion of sustainable resources become critical issues facing human society. In this study, we used humic acids (HAs), which are important derivatives from the low-rank coal, and the transition metal zirconium (Zr) to construct novel Zr-containing catalysts (Zr-HAs) for Meerwein-Ponndorf-Verley (MPV) reactions of biomass-derived platforms. Both commercial HAs and HAs extracted directly from lignite without any purification were used as raw materials to prepare the catalysts. The results showed that Zr-HAs catalysts were highly efficient for the conversion of furfural, with a high furfuryl alcohol yield of up to 97%, and also effective for the conversion of other carbonyl compounds with different structures under mild conditions. This novel strategy to construct catalysts using HAs as raw materials may be beneficial for both value-added utilization of low-rank coal and the conversion of biomass resources.

Self-tuned properties of CuZnO catalysts for hydroxymethylfurfural hydrodeoxygenation towards dimethylfuran production

Brzezińska, Magdalena,Keller, Nicolas,Ruppert, Agnieszka M.

, p. 658 - 670 (2020)

5-Hydroxymethylfurfural (HMF) is a very valuable platform molecule obtained from biomass. It can be catalytically transformed to many industrially relevant products of both oxidation and reduction reactions. In this work, we showed that robust CuZnO can be an efficient, self-tuned catalyst for 2,5-dimethylfuran (DMF) (biofuel additive) synthesis. We showed that CuZnO catalysts can be further activated in the reaction environment and this process depends strongly on the initial catalyst properties and therefore on the catalyst preparation method. Smaller copper particles are more active but more prone to carbon deposit formation. Based on activity tests and extensive characterization, we have concluded that both Cun+ and Cu0 sites are necessary for high HMF conversion. While these two sites favor high conversion and high 2,5-bishydroxymethylfuran (BHMF) yield, the in situ formation of Lewis acid sites is proposed to be necessary for achieving a high DMF yield.

Hydroconversion of 5-Hydroxymethylfurfural to 2,5-Dimethylfuran and 2,5-Dimethyltetrahydrofuran over Non-promoted Ni/SBA-15

Chen, Shuo,Ciotonea, Carmen,De Oliveira Vigier, Karine,Jér?me, Fran?ois,Wojcieszak, Robert,Dumeignil, Franck,Marceau, Eric,Royer, Sebastien

, p. 2050 - 2059 (2020)

The selective hydroconversion of 5-hydroxymethylfurfural (HMF) to biofuels is currently highly sought-for. While the literature has demonstrated that this reaction is possible on promoted Ni catalysts, we show here that a monometallic, non-promoted Ni/SBA-15 catalyst, prepared by incipient wetness impregnation, can convert HMF to 2,5-dimethylfuran (DMF) and to 2,5-dimethyltetrahydrofuran (DMTHF) at 180 °C, in a consecutive way. Through a control over reaction time, high yields to DMF (71 %, at conversion of 93 %) or DMTHF (97 %, at conversion of 100 %) can be achieved. Kinetic modelling suggests a preferential route to DMF via 5-methylfurfural (MFFR) as intermediate, though the route via 2,5-bis(hydroxylmethyl)furan (BHMF) is also present. The favored route in the experimental conditions involves the hydrogenolysis of the hydroxyl group of HMF as first step, followed by the hydrogenation of the aldehyde function, to methylfurfuryl alcohol (MFOL). It is suggested a higher reaction rate of hydrogenation or hydrogenolysis of the side group is linked to the presence of a methyl group in the molecule. No hydrogenation of the furan ring is detected on the intermediates.

Direct one-pot conversion of monosaccharides into high-yield 2,5-dimethylfuran over a multifunctional Pd/Zr-based metal-organic framework@sulfonated graphene oxide catalyst

Insyani, Rizki,Verma, Deepak,Kim, Seung Min,Kim, Jaehoon

, p. 2482 - 2490 (2017)

A one-pot conversion of monosaccharides (fructose and glucose) into high-yield 2,5-dimethylfuran (2,5-DMF) is demonstrated over a multifunctional catalyst obtained by loading Pd on a Zr-based metal-organic framework (UiO-66) that is deposited on sulfonated graphene oxide (Pd/UiO-66@SGO). The Br?nsted acidity associated with UiO-66@SGO activates the fructose dehydration to form 5-hydroxymethylfurfural (5-HMF), while the Pd nanoparticles further convert 5-HMF to 2,5-DMF by hydrogenolysis and hydrogenation. The results show that under the optimized reaction conditions of 160 °C and 1 MPa H2 in tetrahydrofuran for 3 h, the yield of 2,5-DMF is as high as 70.5 mol%. This value is higher than the previously reported values, and the direct conversion of fructose can be achieved without additional purification of 5-HMF from the reaction mixture. In addition, for the first time, glucose is converted to 2,5-DMF with a high yield of 45.3 mol%. A recyclability test suggests that the 4.8 wt% Pd loaded on the UiO-66@SGO catalyst can be re-used up to five times.

A Pd-Catalyzed in situ domino process for mild and quantitative production of 2,5-dimethylfuran directly from carbohydrates

Li, Hu,Zhao, Wenfeng,Riisager, Anders,Saravanamurugan, Shunmugavel,Wang, Zhongwei,Fang, Zhen,Yang, Song

, p. 2101 - 2106 (2017)

An in situ domino process has been developed to be highly efficient for direct and mild conversion of various hexose sugars to the biofuel 2,5-dimethylfuran in almost quantitative yields, without separation of unstable intermediates at 120 °C in n-butanol, by using polymethylhydrosiloxane and hydrophobic Pd/C as a H-donor and a bifunctional catalyst, respectively. Among the cascade reactions, the hydrosilylation process was confirmed by deuterium-labeling and kinetic studies to be favorable for sugar dehydration and exclusively acts on deoxygenation of in situ formed intermediates including furanic alcohols and aldehydes to DMF via a hydride transfer process that was facilitated by an alcoholic solvent. The catalytic system is more selective than the H2- participated counterpart, and could be scaled up with only 0.04 mol% catalyst loading, giving DMF in a comparable yield of 85%. Moreover, Pd(0) was demonstrated to be the active species for deoxygenation, and the heterogeneous catalyst exhibited good recyclability with little elemental leaching.

Synthetic Methods and Reactions; 99. Preparation of Cyclic Ethers over Superacidic Perfluorinated Resinsulfonic Acid (Nafion-H) Catalyst

Olah, George A.,Fung, Alexander P.,Malhotra, Ripudaman

, p. 474 - 476 (1981)

-

Insights into the Ring-Opening of Biomass-Derived Furanics over Carbon-Supported Ruthenium

Gilkey, Matthew J.,Mironenko, Alexander V.,Yang, Leerang,Vlachos, Dionisios G.,Xu, Bingjun

, p. 3113 - 3121 (2016)

The selective ring-opening of cellulose-derived furanic molecules is a promising pathway for the production of industrially relevant linear oxygenates, such as 1,6-hexanediol. 2,5-Dimethylfuran (DMF) is employed as a model compound in a combined experimental and computational investigation to provide insights into the metal-catalyzed ring-opening. Ring-opening to 2-hexanol and 2-hexanone and ring-saturation to 2,5-dimethyltetrahydrofuran (DMTHF) are identified as two main parallel pathways. DFT calculations and microkinetic modeling indicate that DMF adsorbs on Ru in an open-ring configuration, which is potentially a common surface intermediate that leads to both ring-opening and ring-saturation products. Although the activation barriers for the two pathways are comparable, the formation of DMTHF is more thermodynamically favorable. In addition, steric interactions with co-adsorbed 2-propoxyl, derived from the solvent, and the oxophilic nature of Ru play key roles to determine the product distribution: the former favors less bulky, that is, ring-closed, intermediates, and the latter retards O?H bond formation. Finally, we show that the hydrodeoxygenation of oxygenated furanics, such as 5-methylfurfural and (5-methyl-2-furyl)methanol, on Ru occurs preferentially at oxygen-containing side groups to form DMF, followed by either ring-opening or ring-saturation.

STEREOCHEMISTRY OF THE IODOCYCLIZATION OF UNSATURATED ALCOHOLS

Gevaza, Yu. I.,Kupchik, I. P.,Staninets, V. I.

, p. 24 - 26 (1981)

The corresponding tetrahydrofuran derivatives were obtained by iodination of δ,ε-unsaturated alcohols containing substituents attached to the α-carbon atom.The effect of substituents on the stereochemistry of the products and the rate of iodination of the

Ring closure reactions of substituted 4-pentenyl-1-oxy radicals. The stereoselective synthesis of functionalized disubstituted tetrahydrofurans

Hartung,Gallou

, p. 6706 - 6716 (1995)

N-(Alkyloxy)pyridine-2(1H)-thiones 3 and benzenesulfenic acid O-esters 5 have been synthesized from substituted 4-pentenols 1 or the derived tosylates. Compounds 3 and 5 are efficient sources of free alkoxy radicals 6 which undergo synthetically useful fast ring closure reactions 6 → 8 [k(exo) = (2 ± 1) x 108 s-1 to (6 ± 2) x 109 s-1 (T = 30 ± 0.2°C)]. Tetrahydrofurfuryl radicals 8 can be trapped with, e.g., hydrogen or chlorine atom donors to afford either trans- or cis-disubstituted tetrahydrofurans 10 or 12 depending on the substitution pattern of the 4-pentenyloxy radical. Substituted tetrahydropyrans 11 or 13 are formed in the minor 6-endo-trig cyclization. According to the data of competition kinetics, the observed stereoselectivities in free alkoxy radical cyclizations arise from steric interactions between the substituents in the transition state of the ring closure reactions. Alkyl substituents cause small differences in the measured relative rate constants of 5-exo cyclizations which are reminiscent of the data obtained from the rearrangements of alkyl-substituted 5-hexenyl radicals. Likewise, a stereochemical model for oxygen radical cyclization is proposed where the pentenyloxy chain adopts a six-membered, chairlike transition state with the alkyl substituents preferentially situated in the pseudoequatorial positions leading to 2,5-trans-, 2,4-cis-, and 2,3-trans-substituted tetrahydrofurfuryl radicals 8 as the major intermediates.

Robust and recyclable nonprecious bimetallic nanoparticles on carbon nanotubes for the hydrogenation and hydrogenolysis of 5-hydroxymethylfurfural

Yu, Lili,He, Le,Chen, Jin,Zheng, Jianwei,Ye, Linmin,Lin, Haiqiang,Yuan, Youzhu

, p. 1701 - 1707 (2015)

Selective hydrogenation and hydrogenolysis of 5-hydroxymethylfurfural were performed with carbon nanotube-supported bimetallic Ni-Fe (Ni-Fe/CNT) catalysts. The combination of Ni and Fe in an appropriate atomic ratio of Ni/Fe (2.0) significantly increased the selectivity to 2,5-furandimethanol or 2,5-dimethylfuran depending on the reaction temperature. The selectivities to 2,5-furandimethanol and 2,5-dimethylfuran were as high as 96.1 % at 383 K and 91.3 % at 473 K, respectively. The characterization results confirmed that bimetallic particles with sizes less than 7 nm were formed on the catalyst. Several key molecules related to 5-hydroxymethylfurfural transformation were used to investigate the product distribution and reaction pathway. The results indicated that the formation of Ni-Fe alloy species is beneficial to the selective cleavage of the C-O bond. Recycling experiments showed that the catalyst can be easily separated with a magnet and reused several times without significant loss of activity.

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Cekovic,Z. et al.

, p. 2021 - 2026 (1979)

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In situ generation of water-stable and -soluble ruthenium complexes of pyridine-based chelate-ligands and their use for the hydrodeoxygenation of biomass-related substrates in aqueous acidic medium

Minard, Thomas A.,Oswin, Christopher T.,Waldie, Fraser D.C.,Howell, Jennifer K.,Scott, Benjamin M.T.,Mondo, Domenico Di,Sullivan, Ryan J.,Stein, Benjamin,Jennings, Michael,Schlaf, Marcel

, p. 175 - 187 (2016)

The complexes [Ru(2,2′-dipicolylamine)(OH2)3](OTf)2 and [Ru(6,6′-bis(aminomethyl)-2,2′-bipyridine)(OH2)2](OTf)2 can be prepared by reaction of 2,2′-dipicolylamine or 6,6′-bis(aminomethyl)-2,2′-bipyridine with [RuIII(DMF)6](OTf)3 in aqueous medium. During the reaction an in situ reduction from a paramagnetic RuIII to a diamagnetic RuII-complexes occurs with one equivalent of DMF acting as the reducing agent for two ruthenium centres by its reaction with water and decomposition to dimethylammonium triflate and CO2 generating an additional equivalent of HOTf in the process. The complex solutions are active as catalysts for the hydrogenation of 2,5-hexanedione and 2,5-dimethylfuran to 2,5-hexanediol and 2,5-dimethyltetrahydrofuran with both complexes realizing very high yields (>95% combined yield of the two products with the selectivity determined as a function of added acid co-catalyst). The 2,2′-dipicolylamine complex is stable to 150?°C, while the 6,6′-bis(aminomethyl)-2,2′-bipyridine complex is stable to 200?°C allowing the in situ hydrolysis of 2,5-dimethylfuran to the 2,5-hexanedione and thus direct conversion to the same products in up to 78% combined yield. The effects of co-solvents, acid co-catalysts and temperature on catalyst activity, decomposition and stability are explored.

-

Cortese

, p. 1519 (1930)

-

Highly active bifunctional Pd-Co9S8/S-CNT catalysts for selective hydrogenolysis of 5-hydroxymethylfurfural to 2,5-dimethylfuran

Liao, Weiping,Zhu, Zhiguo,Chen, Naimeng,Su, Ting,Deng, Changliang,Zhao, Yuchao,Ren, Wanzhong,Lü, Hongying

, (2020)

A series of Pd-Co bimetallic catalysts were smoothly synthesized using sulfur-modified carbon nanotubes (S-CNT) as support by impregnation method. Those catalysts were characterized by XRD, XPS, TEM, SEM, H2-TPR, TGA, and nitrogen adsorption-de

Generation of alkyl hypochlorites in oxidation of alcohols with carbon tetrachloride catalyzed by vanadium and manganese compounds

Khusnutdinov,Shchadneva,Baiguzina,Lavrentieva,Dzhemilev

, p. 2074 - 2079 (2002)

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.

Ga+-catalyzed hydrosilylation? about the surprising system Ga+/HSiR3/olefin, proof of oxidation with subvalent Ga+and silylium catalysis with perfluoroalkoxyaluminate anions

Barthélemy, Antoine,Glootz, Kim,Hanske, Annaleah,Krossing, Ingo,Scherer, Harald

, p. 439 - 453 (2022/01/22)

Already 1 mol% of subvalent [Ga(PhF)2]+[pf]- ([pf]- = [Al(ORF)4]-, RF = C(CF3)3) initiates the hydrosilylation of olefinic double bonds under mild conditions. Reactions with HSiMe3 and HSiEt3 as substrates efficiently yield anti-Markovnikov and anti-addit

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