Higher olefin hydroformylation in organic/aqueous biphasic system accelerated by double long-chain cationic surfactants

The double long-chain cationic surfactants (DLCS) were used in higher olefin hydroformylation catalyzed by water-soluble rhodium catalyst in aqueous/organic biphasic system. The reaction rate was greatly accelerated and the value of TOF (turn over frequency defined as the moles of converted olefin per mole Rh per hour) in 1-dodecene hydroformylation could achieve 2291 h(-1) even without stirring. When the reaction was carried out with stirring rate of 400 rpm, TOF increased to 7472 h(-1). These values of TOF were comparable with that in homogeneous catalysis system. The phenomenon is attributed to the formation of vesicle and the enrichment of rhodium catalyst in the interfacial layer, as well as the high transfer rate of olefins from the organic phase to the interface of vesicle. The acceleration mechanism of DLCS in biphasic catalysis was discussed. (c) 2006 Elsevier B.V. All rights reserved.