- Preparation method of pyruvic aldehyde glycol
-
The invention relates to a method for preparing pyruvic aldehyde glycol, which comprises the following step of: reacting 1, 3-dihydroxy acetone with alcohol in the presence of a catalyst to obtain the pyruvic aldehyde glycol.
- -
-
Paragraph 0085-0087; 0090; 0091; 0098; 0099; ...
(2021/10/13)
-
- Synergistic Production of Methyl Lactate from Carbohydrates Using an Ionic Liquid Functionalized Sn-Containing Catalyst
-
Considerable progress has been made recently in the catalytic conversion of renewable biomass resources to methyl lactate (MLA). However, conceiving eco-friendly and effective catalytic systems for the production of MLA from biomass carbohydrates remains a key challenge. Herein, we report a multifunctional catalyst Sn(salen)/IL, consisting of a Sn(salen) complex and an imidazolium-based ionic liquid (IL), which acts via an intramolecular synergistic effect to convert carbohydrates to MLA in methanol. The versatile properties of the resultant catalyst were revealed to be responsible for the conversion of fructose to MLA and the efficient suppression of undesired side reactions. This catalyst displayed outstanding catalytic activity, high selectivity, and excellent recyclability, giving an MLA yield of up to 68.9 % at 160 °C after 2 h. The results of this study will contribute to new approaches for designing synergistic catalysts for producing liquid fuels and chemicals from biomass resources.
- Wang, Fenfen,Wen, Yi,Fang, Yanxiong,Ji, Hongbing
-
p. 4154 - 4161
(2018/09/06)
-
- Synthesis of Sn-Beta with Exclusive and High Framework Sn Content
-
Sn-Beta zeolite was prepared by acid dealumination of Beta zeolite, followed by dehydration and impregnation with anhydrous SnCl4. The formation of extraframework Sn (EFSn) species was prevented by the removal of unreacted SnCl4 in a methanol washing step prior to calcination. The resulting Sn-Beta zeolites were characterized by X-ray diffraction, Ar physisorption, NMR, UV/Vis, and FTIR spectroscopy. These well-defined Lewis acid zeolites exhibit good catalytic activity and selectivity in the conversion of 1,3-dihydroxyacetone to methyl lactate. Their performance is similar to a reference Sn-Beta zeolite prepared by hydrothermal synthesis. Sn-BEA zeolites that contain EFSn species exhibit lower catalytic activity; the EFSn species also catalyze formation of byproducts. DFT calculations show that partially hydrolyzed framework Sn-OH species (open sites), rather than the tetrahedral framework Sn sites (closed sites), are the most likely candidate active sites for methyl lactate formation.
- Van Der Graaff, William N. P.,Li, Guanna,Mezari, Brahim,Pidko, Evgeny A.,Hensen, Emiel J. M.
-
p. 1152 - 1160
(2015/04/14)
-
- Highly active and recyclable Sn-MWW zeolite catalyst for sugar conversion to methyl lactate and lactic acid
-
Not just sugar! Lewis-acidic Sn-MWW zeolites are obtained through postsynthesis functionalization of deboronated B-MWW with Sn. These materials are highly active, selective, and recyclable catalysts for the conversion of triose sugars to methyl lactate (in methanol) and lactic acid (in water). They also demonstrate good performance in the conversion of hexose sugars and sucrose to methyl lactate. Copyright
- Guo, Qiang,Fan, Fengtao,Pidko, Evgeny A.,Van Der Graaff, William N. P.,Feng, Zhaochi,Li, Can,Hensen, Emiel J. M.
-
p. 1352 - 1356
(2013/09/12)
-
- Efficient preparation of α-ketoacetals
-
The Weinreb amides 2a,b were prepared from the a,a-dimethoxyacetic acids 1c,d. A number of representative nucleophilic additions (RMgX and RLi) on 2 afforded a-ketoacetals 3a-j in 70-99% yield. These compounds represent a versatile arrangement of functional groups of significant synthetic value, as demonstrated in the synthesis of (±)-salbutamol.
- Ayala-Mata, Francisco,Barrera-Mendoza, Citlalli,Jimenez-Vazquez, Hugo A.,Vargas-Diaz, Elena,Zepeda, L. Gerardo
-
p. 13864 - 13878
(2013/03/13)
-
- The smallest vicinal tricarbonyl compound as a monohydrate and tetracarbonyl compound as a Thiane Derivative- First effective synthesis, characterization and chemistry
-
An effective synthesis of 2-oxo-l,3-propanedial monohydrate or mesoxaldehyde (6a) and the first synthesis of 2, 3-dioxo-1,4-butanedial (18) as a thiane derivative are reported. These first members of the smallest vicinal tri- and tetracarbonyl compounds are stabilized by conversion to thiane derivatives 8, 9, 10, 11, 12, 15 and 19, which can be isolated as long-lived compounds at room temperature. The structures of these novel thianes 8, 10, 12 and 15 were confirmed by their X-ray crystal structures. The synthesis of a series of protected as well as free heterocyclic aldehydes (pterins and quinoxa-lines) by the use of the appropriate tricarbonyl compounds is also reported. Additionally, a one-step synthetic strategy to prepare a series of different biheterocycles with the smallest vicinal tetracarbonyl compound is demonstrated. Wiley-VCH Verlag GmbH & Co. KGaA.
- Goswami, Shyamaprosad,Maity, Annada C.,Fun, Hoong-Kun,Chantrapromma, Suchada
-
experimental part
p. 1417 - 1426
(2009/08/07)
-
- A practical route to pyrazines and quinoxalines, and an unusual synthesis of benzimidazoles
-
1,2-Dicarbonyl compounds can be accessed by a radical addition-transfer of xanthates and used for the synthesis of pyrazines and quinoxalines, as well as in an unusual approach to benzimidazoles.
- Mougin, Catherine,Sancon, Julien,Zard, Samir Z.
-
p. 211 - 218
(2008/09/17)
-
- Tin-catalyzed conversion of trioses to alkyl lactates in alcohol solution
-
Tin chlorides, SnCl2 and SnCl4·5H2O are excellent catalysts for the reactions of trioses, dihydroxyacetone and glyceraldehyde with alcohols (MeOH, EtOH and nBuOH) to give alkyl lactates, whose reaction mechanism involves the intermediary formation of pyruvic aldehyde followed by its esterification, which is distinctively promoted by tin halides. The Royal Society of Chemistry 2005.
- Hayashi, Yukiko,Sasaki, Yoshiyuki
-
p. 2716 - 2718
(2007/10/03)
-
- Reactions of alcohols with α-alkoxyacroleins at room temperature
-
The first stage of the reactions of alcohols with α-alkoxyacroleins in an acidic medium at 20°C under kinetically controlled conditions is the Markovnikoff addition at the C=C bond to form 2,2-dialkoxypropanals (methylglyoxal ketals). Under conditions of thermodynamic control, subsequent acetalization of the aldehyde group occurs to form 1,1,2,2-tetraalkoxypropanes. When the duration of the reaction is further increased in the absence of a water acceptor, the ketal group undergoes hydrolysis and methylglyoxal acetals are formed. A method was developed for the preparation of methylglyoxal ketals.
- Keiko,Chuvashev,Stepanova,Voronkov
-
p. 2422 - 2425
(2007/10/03)
-
- A Study of Rearrangement of some 1,3-Dimethoxyalkan-2-ones
-
1,3-Dialkoxyacetones, 1-alkyl- and 1-(substituted phenyl)-, 1-alkanoyl-1,3-dimethoxyacetones, and methyl 2,4-dimethoxyacetoacetate were shown to undergo acid-catalysed rearrangement to give respectively methylglyoxal dialkyl acetals, 3-substituted methylglyoxal dimethyl acetals, 5-alkyl-3-methoxy- and 4,5-dimethoxyfuran-2(5H)-ones. 1-(Substituted aroyl)-1,3-dimethoxyacetones underwent only scission to give substituted ω-methoxyacetophenones.Methyl 2-alkyl-2,4-dimethoxyacetoacetates, 3- and 1-methoxy-, and 1,5-dimethoxypentane-2,4-diones were not affected by similaracid treatment except for the fact that they suffered some limited C-C bond scissions.Implications related to rearrangement mechanisms are discussed.
- Yu, Yin,Chen, Guo-qiang,Zhu, Jun,Zhang, Xu-sheng,Chen, Shu-xin,et al.
-
p. 2239 - 2243
(2007/10/02)
-
- Process for synthesizing methyl glyoxal acetals
-
A one-step process for the synthesis of methyl glyoxal acetals from dihydroxyacetone wherein dihydroxyacetone, an alkanol and an acid catalyst are reacted to produce the acetals.
- -
-
-