Fluoride-free and low concentration template synthesis of hierarchical Sn-Beta zeolites: efficient catalysts for conversion of glucose to alkyl lactate
Hierarchical Sn-Beta was prepared by a hydrothermal postsynthesis method. It shows higher catalytic activity for conversion of glucose to alkyl lactate than microporous Sn-Beta hydrothermally synthesized in fluoride media.
Brønsted acid ionic liquid catalyzed formation of pyruvaldehyde dimethylacetal from triose sugars
作者:Shunmugavel Saravanamurugan、Anders Riisager
DOI:10.1016/j.cattod.2012.07.001
日期:2013.2
A series of sulfonic acid functionalized ionic liquids (SO3H-ILs) have been synthesized, characterized and investigated as catalysts for the conversion of the triose sugars, 1,3-dihydroxyacetone (DHA) and glyceraldehyde (GLA), to pyruvaldehyde dimethylacetal (PADA) in methanol. Depending on the reaction conditions and the applied SO3H-ILs a good yield of up to 52% of PADA was obtained. Under identical
Stereochemical aspects of the formation of diastereoisomeric 3-acetyl-2-(polyacetoxyalkyl)-5-phenyl-2,3-dihydro-1,3,4-oxadiazoles
作者:László Somogyi
DOI:10.1016/0008-6215(88)84088-6
日期:1988.10
arabino -(tetra-acetoxybutyl)]- [(−)- and (+)- 4a , (−)- 4b ] and 3-acetyl-2-[ d - manno -(penta-acetoxypentyl)]-5-phenyl-2,3-dihydro-1,3,4-oxadiazoles [(+)- 4d ] via cyclisation of the corresponding ( O -acetylated) aldose benzoylhydrazones ( 2a,b,d ) under acetylating conditions is described. The stereochemicalaspects of the formation of C-2 epimeric oxadiazolines [ e.g. , (−)- and (+)- 4a ] are discussed
Tin-catalyzed conversion of trioses to alkyl lactates in alcohol solution
作者:Yukiko Hayashi、Yoshiyuki Sasaki
DOI:10.1039/b501964h
日期:——
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 pyruvicaldehyde followed by its esterification, which is distinctively promoted by tin halides.
Reactions of alcohols with α-alkoxyacroleins at room temperature
作者:N. A. Keiko、Yu. A. Chuvashev、L. G. Stepanova、M. G. Voronkov
DOI:10.1007/bf02641546
日期:1998.12
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 undegroes hydrolysis