Modified Ti/MCM-41 catalysts for enantioselective epoxidation of styrene
نویسندگان
چکیده
منابع مشابه
Combinatorial evolution of site- and enantioselective catalysts for polyene epoxidation
Selectivity in the catalytic functionalization of complex molecules is a major challenge in chemical synthesis. The problem is magnified when there are several possible stereochemical outcomes and when similar functional groups occur repeatedly within the same molecule. Selective polyene oxidation provides an archetypical example of this challenge. Historically, enzymatic catalysis has provided...
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Ti-MCM-41 was synthesized at pH 3, 7 and 11. The titanium content was determined by AAS and found to be 4%, 3.2% and 4.5%, respectively. In order to increase the titanium content in Ti-MCM-41, Ti(IV) ions were grafted onto Ti-MCM-41 using TiCl4 in toluene and Ti(OBu)4 in ethanol. The incorporation of Ti was determined to be 28% and 30%, respectively. The oxidation of olefins such as cyclopenten...
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Some time ago we reported the oxidation of 2,3-unsaturated hexopyranosides and 2-Cmethylene glycosides with hydrogen peroxide in the presence of molybdenum trioxide catalyst to give the corresponding anomeric hydroperoxides 1-5. Relatively stable hydroperoxides 1-5 were used for enantioselective oxidation of prochiral alcohols and sulfides in the presence of Ti(OiPr)4 with stereoselectivities v...
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ژورنال
عنوان ژورنال: Journal of Molecular Catalysis A: Chemical
سال: 2016
ISSN: 1381-1169
DOI: 10.1016/j.molcata.2016.05.001