4228-48-2Relevant academic research and scientific papers
Biobased catalyst in biorefinery processes: Sulphonated hydrothermal carbon for glycerol esterification
De La Calle, Carlos,Fraile, José M.,García-Bordejé, Enrique,Pires, Elísabet,Roldán, Laura
, p. 2897 - 2903 (2015)
Sulphonated hydrothermal carbon (SHTC), obtained from d-glucose by mild hydrothermal carbonisation and subsequent sulphonation with sulphuric acid, is able to catalyse the esterification of glycerol with different carboxylic acids, namely, acetic, butyric and caprylic acids. Product selectivity can be tuned by simply controlling the reaction conditions. On the one hand, SHTC provides one of the best selectivity towards monoacetins described up to now without the need for an excess of glycerol. On the other hand, excellent selectivity towards triacylglycerides (TAG) can be obtained, beyond those described with other solid catalysts, including well-known sulphonic resins. Recovery of the catalyst showed partial deactivation of the solid. The formation of sulphonate esters on the surface, confirmed by solid state NMR, was the cause of this behaviour. Acid treatment of the used catalyst, with subsequent hydrolysis of the surface sulphonate esters, allows SHTC to recover its activity. The higher selectivity towards mono- and triesters and its renewable origin makes SHTC an attractive catalyst in biorefinery processes.
Enzymatic preparation of enantiomerically pure sn-2,3-diacylglycerols: A stereoselective ethanolysis approach
Piyatheerawong, Weera,Yamane, Tsuneo,Nakano, Hideo,Iwasaki, Yugo
, p. 603 - 607 (2007/10/03)
Stereoselective ethanolysis of monoacid TAG by immobilized Rhizomucor miehei lipase (RML) was studied for preparation of optically pure sn-2,3-DAC. Trioctanoylglycerol (TO) was used as a model substrate. The enantiomeric purity of the product, sn-2,3-dioctanoylglycerol (sn-2,3-DO), was very high (percent enantiomeric excess > 99%) when an excess of ethanol was used. The result indicated that RML was highly stereosRMLelective toward the sn-1 position of TO under conditions of excess ethanol. The stereoselectivity of RML depended on the amount of ethanol. The larger the amount of ethanol was, the higher the stereoselectivity became. After optimizing the parameters such as reactant molar ratio, water content, and temperature, (ethanol/TO molar ratio = 31:1 and water content = 7.5 wt% of the reactants at 25°C), optically pure sn-2,3-DO was obtained at 61.1 mol% in the glyceride fraction in 20 min. The above conditions were further applied for ethanolysis of monoacid TAG with different acyl groups such as tridecanoylglycerol (C10:0), tridodecanoylglycerol (C12:0), tritetradecanoylglycerol (C14:0) and trioctadecenoylglycerol [triolein, (C18:1)]. The yields and enantiomeric purities of 1,2(2,3)-DAG were dramatically reduced when TAG with FA longer than decanoic acid were used. Copyright
SYNTHESIS OF A PHOTOREACTIVE DIGLYCERIDE LIGAND OF PROTEIN KINASE C
Pavlova, Yu. B.,Vodovozova, E. L.,Molotkovskii, Yu. G.
, p. 378 - 381 (2007/10/02)
The synthesis is described of a 1,2-diglyceride containing a residue of 12-dodecanoic acid that is capable of activating protein kinase C.Key words: 1,2-diglyceride; photoreactively labeled; protein kinase
