Homogeneous epoxidation molybdenum complexes

The tert-huty hydroperoxide is then mixed with a catalyst solution to react with propylene. Some TBHP decomposes to TBA during this process step. The catalyst is typically an organometaHic that is soluble in the reaction mixture. The metal can be tungsten, vanadium, or molybdenum. Molybdenum complexes with naphthenates or carboxylates provide the best combination of selectivity and reactivity. Catalyst concentrations of 200—500 ppm in a solution of 55% TBHP and 45% TBA are typically used when water content is less than 0.5 wt %. The homogeneous metal catalyst must be removed from solution for disposal or recycle (137,157). Although heterogeneous catalysts can be employed, elution of some of the metal, particularly molybdenum, from the support surface occurs (158). References 159 and 160 discuss possible mechanisms for the catalytic epoxidation of olefins by hydroperoxides. 

The epoxidation of petrochemical alkenes is an intensely investigated oxidation reaction and in recent years numerous homogeneous catalysts have been developed for this reaction. However, so far the catalytic epoxidation of fatty compounds has been investigated only marginally. Sobczak and Ziolkowski reported on the epoxidation of oleic acid with organic hydroperoxides catalyzed by molybdenum complexes [37]. Typical homogeneous catalysts include Mo(CO)6 and Mo02(acac)2. 

J. Sobczak, J. J. Zioikowski, The molybdenum(V) complexes as the homogeneous and heterogenized catalysts in epoxidation reactions of olefins with the organic hydroperoxides, /. Mol. Catal. 3 (1977/1978) 165. 

B., Balula, S., Gago, S., et al. (2009). Comparison of Liquid-Phase Olefin Epoxidation Catalysed by Dichlorobis-(Dimethylformamide) Dioxomolybdenum(Vl) in Homogeneous Phase and Grafted onto MCM-41,7. Mo/. Catal.A Chem.,291,pp. 110-117 Yang, Q., Coperet, C., Li, C., et al. (2003). Molybdenum Containing Surface Complex for Olefin Epoxidation, New J. Chem., 27, pp. 319-323. 

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