- One-pot production of diethyl maleate via catalytic conversion of raw lignocellulosic biomass
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The conversion of lignocellulose into a value-added chemical with high selectivity is of great significance but is a big challenge due to the structural diversities of biomass components. Here, we have reported an efficient approach for the one-step conversion of raw lignocellulose into diethyl maleate by the polyoxometalate ionic liquid [BSmim]CuPW12O40 in ethanol under mild conditions. The results reveal that all of the fractions in biomass, i.e., cellulose, lignin and hemicellulose, were simultaneously converted into diethyl maleate (DEM), achieving a 329.6 mg g-1 yield and 70.3% selectivity from corn stalk. Importantly, the performance of the ionic liquid catalyst [BSmim]CuPW12O40 was nearly twice that of CuHPW12O40, which can be attributed to the lower incorporation of the Cu2+ site in [BSmim]CuPW12O40. Hence, this process opens a promising route for producing bio-based bulk chemicals from raw lignocellulose without any pretreatment.
- Cai, Zhenping,Chen, Rujia,Zhang, Hao,Li, Fukun,Long, Jinxing,Jiang, Lilong,Li, Xuehui
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supporting information
p. 10116 - 10122
(2021/12/24)
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- INDICYANINE DYES AND THE DERIVATIVES THEREOF FOR ANALYSING BIOLOGICAL MICROMOLECULES
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The invention relates to two series of synthesised indolenine pentamethine dyes (37 compounds) comprising a reactive group in the third and fifth positions of the indolenine cycle, respectively. A method for producing, extracting and purifying the dyes and the precursors thereof, consisting in determining the absorption and fluorescence maxima, molecular extinction factors, fluorescence quantum yields, relative fluorescence effectiveness at excitation on a wavelength of 635 nm (detection of 670 nm) and 655 nm (detection of 690 nm), relative light stability and comparative sensitivity of detection of marked oligonucleotides on biochips of the claimed dyes, is disclosed. The use of the claimed dyes in the form of fluorescent marks for oligonucleotide and protein chips is also disclosed.
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Page/Page column 54-55
(2010/04/23)
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- PROCESS FOR PRODUCING TETRAALKOXYPROPANE AND DERIVATIVE THEREOF
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In view of the fact that a methyl vinyl ether, which is useful as a starting material for the synthesis of tetraalkoxypropane useful as a skeleton-forming agent having a high reactivity usable as a starting material, etc. for a pharmaceutical and agrochemical intermediates such as a pyrazole derivative or pyrimidine derivative, particularly 1,1,3,3-tetramethoxypropane, is in a gaseous state and difficult to use for industrial production, tetraalkoxypropane useful as a skeleton-forming agent for a pharmaceutical and agrochemical intermediate such as a pyrazole derivative or pyrimidine derivative is easily produced on an industrial scale by using the industrially useable propoxyvinyl ether, as a starting material, without using a gaseous state methyl vinyl ether.
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Page/Page column 6
(2008/06/13)
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- Process for the preparation of malondialdehyde-derivatives
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Process for the preparation of malondialdehyde-derivatives by reacting vinylesters with orthoesters in the presence of a precious metal catalyst.
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- Process for preparing acetals of malondialdehyde
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A process directed to the preparation of acetals of malondialdehyde by reacting alkylvinyl ethers or esters with ortho formates in the gas phase with a heterogeneous catalyst.
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Page column 5
(2008/06/13)
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- Ozonolysis of Olefins, I. - Ozonolysis of 1,4-Cyclohexadiene and Acid-Catalysed Reaction of Primary Cleavage Products
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The reaction of 1,4-cyclohexadiene (1) with ozone under different reaction conditions was investigated.Complete ozonolysis of 1 in chloroform led to a highly explosive ozonide.Oxidative ozonolysis gave malonic acid in 30percent yield, ozonolysis in alcoholic solutions of HCl gave alkyl 3,3-dialkoxypropionates 3 in 60-70percent yield and small amounts of the 1,1,3,3-tetraalkoxypropane 4 as well as dialkyl malonate 5.Partial ozonolysis of1 in HCl/methanol led to a mixture of 3,5 and the corresponding (Z)-3-hexene derivatives 6a-c.Depending on the reaction time and concentration of HCl, also the two methanol addition products 7b and 7d could be obtained.To verify the structure of these two compounds, 4-methoxycyclohexene (8) was ozonized in HCl/methanol, which gave a mixture of 7a-d.
- Mittelbach, Martin,Poklukar, Norbert,Junek, Hans
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p. 185 - 188
(2007/10/02)
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- Enantioselective Saponification of Diacetates of 2-Nitro-1,3-propanediols by Pig-Liver Esterase and Preparation of Enantiomerically Pure Derivatives of 2-Nitro-allylic Alcohols (Chiral Multiple-Coupling Reagents)
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The reproducible enantioselective saponification of open-chain and cyclic diacetates of meso-2-nitro-1,3-propanediols (see 4b-13b) with pig-liver esterase (PLE) gives monoacetates (see 4c-13c) of >95percent enantiomeric excess.The Re enantiotopic acetate group appears to be saponified preferentially, as proved by the X-ray crystal structure analysis of three camphanoates 4d, 6d, and 7d.Elimination of H2O or AcOH from the hydroxy acetates thus available gives derivatives of nitro-allylic alcohols (see 20-24, 27, and 29) which are subjected to diastereoselective Michael additions or SN2' substitutions.
- Eberle, Martin,Egli, Martin,Seebach, Dieter
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- CONDENSATION OF o-PHENYLENE DIAMINE AND SUBSTITUTED ACROLEINS TO FORM MACROHETEROCYCLES
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The reaction of o-phenylene diamine with β-alkoxy-, β-dimethylamino-, and β-acetoxy-α-alkyl- or α-arylacroleins has been studied.A new synthesis of 7,16-diaryldihydrodibenzo-tetraazaannulenes was developed, and the syntheses of 5,14 dihydrodibenzoteraazaannulene and 7,16-dialkyldihydrodibenzotetraazaannulenes were improved. 5,14-Dihydrodibenzotetraazaannulenes were synthesized with various substituents in the benzene rings and at possitions 7 an 16.
- Yatluk, Yu. G.,Suvorov, A. L.
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p. 316 - 320
(2007/10/02)
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- SYNTHESIS AND SOME PROPERTIES OF CYCLIC ACETALS OF MALONALDEHYDE
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The Lewis acid-catalyzed addition of cyclic orthoformates to vinyl ethyl ether, which leads to the formation of malonaldehyde acetals, was studied.It is shown that of the linear-cyclic malonaldehyde acetals, 2-(2,2-diethoxyethyl)- and 5,5-dimethyl-2-(2,2-diethoxyethyl)-1,3-dioxanes are stable.The transacetalization of 1,1,3,3-tetraethoxypropane with 1,2- and 1,3-diols, which leads to the formation of cyclic malonaldehyde acetals, was studied.The physicochemical constants of the acetals were determined, and their 1H and 13C NMR spectra are described.
- Imashev, U. B.,Kalashnikov, S. M.,Gordeeva, G. N.
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p. 369 - 373
(2007/10/02)
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- Chemistry of enol ethers. LI. Reaction of vinyl silyl ethers with orthoformic esters
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The silyl ethers of enolic forms of ketones react with orthoformates in the presence of zinc chloride at catalyst to form β-ketoacetals.The analogous reaction with the silyl ethers of enolic forms of aldehydes leads to the formation of the tetraacetals of 1,3-dialdehydes.
- Makin, S. M.,Kruglikova, R. I.,Popova, T. P.,Tagirov, T. K.
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p. 630 - 634
(2007/10/02)
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