19780-16-6Relevant academic research and scientific papers
Synthesis and unique catalytic performance of single-site Ti-containing hierarchical macroporous silica with mesoporous frameworks
Kamegawa, Takashi,Suzuki, Norihiko,Che, Michel,Yamashita, Hiromi
, p. 2873 - 2879 (2011)
Single-site Ti-containing hierarchical macroporous silica with mesoporous frameworks (Ti-MMS) was successfully prepared by a solvent evaporation method using organic surfactant and poly(methyl methacrylate) (PMMA) colloidal crystals as the template. The formation of a well-defined macroporous structure composed of mesoporous silica walls was characterized by SEM and TEM observations. The successful incorporation of tetrahedrally coordinated Ti oxide moieties within their frameworks was also confirmed by spectroscopic techniques such as UV-vis and XAFS measurements. Comparative studies revealed that Ti-MMS exhibited higher catalytic activities for the epoxidation of linear α-olefin compared to Ti-containing mesoporous silica without macropores (Ti-MS). The reaction rate was significantly enhanced on Ti-MMS depending on increases in the alkyl chain length of linear α-olefins. It was also found that Ti-MMS showed good catalytic performance in the selective epoxidation of methyl oleate, which is a kind of unsaturated fatty acid methyl ester (FAME), under acid-free reaction conditions with tert-butylhydroperoxide (TBHP) because of the advantages of the combination of hierarchical macroporous and mesoporous structures.
Facile synthesis of (Z)-tetracos-5-enoic acid and racemic cis-4-(2-octadecylcyclopropane-1-yl)-butanoic acid
Coxon, Geoffrey D.,Douglas, James D.,Minnikin, David E.
, p. 49 - 53 (2007/10/03)
(Z)-Tetracos-5-enoic acid and racemic cis-4-(2-octadecylcyclopropane-1-yl)- butanoic acid have been prepared from 1-eicosene by a new facile route. Periodic acid cleavage of the epoxide of 1-eicosene gave nonadecanal which was condensed with 4-carboxybutyltriphenylphosphonium bromide to give predominately (Z)-tetracos-5-enoic acid. Simmons-Smith type cyclopropanation of (Z)-tetracos-5-enoic acid gave a minor proportion of racemic cis-4-(2-octadecylcyclopropane-1-yl)-butanoic acid accompanied by major amounts of its methyl ester.
Palladium- and light-enhanced ring-opening of oxiranes by copper chloride
Muzart, Jacques,Riahi, Abdelkhalek
, p. 323 - 336 (2007/10/02)
The yields of chlorohydrins formed by cleavage of epoxides by CuCl2 is increased in the presence of small amounts of PdCl2(MeCN)2.The conversion drops dramatically on carrying out the reaction in the dark.The regiochemistry of the ring-opening is sensitive to the nature of the substituents.
Ketoalkylphospholipids
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, (2008/06/13)
Novel ketoalkylphospholipids, inclusive of salts thereof, of the formula STR1 wherein R1 is an aliphatic hydrocarbon residue containing 10 to 20 carbon atoms, R2 is hydrogen or methoxy, and R3, R4 and R5 are independently hydrogen or C1-5 alkyl, or STR2 represents a cyclic ammonio group, exhibit inhibitory activity against multiplication of tumor cells and antifungal activity.
