6413-26-9Relevant academic research and scientific papers
MOR zeolite supported Bronsted acidic ionic liquid: An efficient and recyclable heterogeneous catalyst for ketalization
Li, Zhang-Min,Zhou, Yan,Tao, Duan-Jian,Huang, Wei,Chen, Xiang-Shu,Yang, Zhen
, p. 12160 - 12167 (2014/03/21)
In order to widen the application of ionic liquids as efficient and renewable heterogeneous catalysts, supported ionic liquids (SILs) have received considerable attention. A novel heterogeneous catalyst MOR zeolite supported Bronsted acidic ionic liquid (BAIL@MOR) was therefore prepared, characterized and applied in the ketalization reaction. The influences of reaction temperature, time, and catalyst loading have also been investigated in detail. Combined characterization results of XRD, FT-IR, SEM, TG-DTG and N 2 adsorption-desorption suggested that the BAIL [CPES-BSIM][HSO 4] was successfully immobilized on the surface of MOR zeolite by covalent bonds. Moreover, the catalytic performance tests demonstrated that the catalyst BAIL@MOR exhibited excellent catalytic activities in the ketalization of cyclohexanone with glycol, 1,2-propylene glycol and 1,3-butylene glycol under mild reaction conditions, as comparable with the homogeneous catalysis of the precursors [BSmim][HSO4] and H2SO4. In addition, the catalyst BAIL@MOR was also found to be reusable five times without a significant loss of its catalytic activity. Thus, the heterogeneous catalyst BAIL@MOR can act as a promising candidate for the ketalization reaction.
Chiral and flexible 2,4-pentanediol-tethered cyclopropanation of olefins with a carbenoid derived from a diazo ester to construct three stereogenic centers
Sugimura, Takashi,Mori, Atsushi,Tai, Akira,Tei, Takahiro,Sakamoto, Yasuhiro,Okuyama, Tadashi
, p. 881 - 890 (2007/10/03)
2,4-Pentanediol-tethered cyclopropanation of an olefin with an internal carbenoid generated from a diazo ester proceeded smoothly to give a chiral adduct having three stereogenic centers under full stereocontrol. The high stereoselectivity was not affected by the structure of the olefinic portion, studied so far with six substrates. Conversion of the product cyclopropane to other optically active compounds is also reported.
Synthesis and stereochemistry of some new chiral spiro-1,3-dioxanes
Grosu, Ion,Ple, Gerard,Mager, Sorin,Martinez, Roberto,Mesaros, Clementina,Del Carmen Camacho, Brigida
, p. 6215 - 6232 (2007/10/03)
The stereoisomerism of some spiro-1,3-dioxanes obtained from chiral 1,3-diols or chiral substituted cyclohexanones is discussed on the basis of the helical chirality of the 1,5-dioxaspiro[5,5]undecane skeleton and of the data of conformational analysis. The influence of the flexibility of the rings on the representative number of isomers and on their NMR spectra is commented. The compositions of the stereoisomers (diastereoisomers and enantiomers) of some representative compounds have been determined by gas chromatography using chiral columns.
ANALYTICAL ENANTIOMER SEPARATION OF ALIPHATIC DIOLS AS BORONATES AND ACETALS BY COMPLEXATION GAS CHROMATOGRAPHY
Schurig, V.,Wistuba, D.
, p. 5633 - 5636 (2007/10/02)
Cyclic boronates and acetals of mono- and dialkylsubstituted 1,2-, 2,3- 1,3-and 1,4-diols have been quantitatively separated into enantiomers by complexation gas chromatography utilizing optically active metal chelates.An efficient, precise and sensitive method for determining enantiomeric purities for volatile glycols is thus available.
