Propene Sumitomo process

Regioselective dimerization of propene to 2,3-dimethylbutenes (DMBs) is currently operated by Sumitomo and BP Chemicals. Both use P(cyclohexyl)3 as the bulky ligand. In the Sumitomo process [7] very high selectivities in DMBs (up to 85 %) are obtained at 20-50 °C, thanks to a sophisticated, highly efficient, Ziegler-type catalyst system (ten times more efficient than those of conventional catalysts) and by using toluene as a solvent. Isomerization of 2,3-dimethyl-1-butene (DMB-1) into 2,3-dimethyl-2-butene (DMB-2) takes place directly in... 

Finally, it is noted that the direct epoxidation of propene with molecular oxygen is potentially more economically attractive than all of the coproduct processes currently in operation. It is indeed a holy grail in oxidation chemistry. Notwithstanding the extensive research on this topic in the last three decades, an industrially viable method for the direct epoxidation of propene has not been forthcoming. Sumitomo has recently announced [67] that they will commercialize a coproduct free route to PO but this probably involves an alkyl hydroperoxide e.g. cumene) oxidant with recycling of the alcohol coproduct [68]. 

I 14 Au NP-catalysed Propene Epoxidation by Dioxygen and Dihydrogen a) Cumene recycling process by Sumitomo Chemical Co. Ltd. 

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