19780-16-6Relevant articles and documents
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.
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.