Comparison of phase transfer agents in the aqueous biphasic hydroformylation of higher alkenes

Abstract

The Rh-catalyzed aqueous biphasic hydroformylation with the bidentate ligand SulfoXantPhos was investigated for different phase transfer agents (PTA). As such, polymer latices and microemulsions formed by non-ionic surfactants were used. In general, a higher PTA concentration enhances the reaction progress. The feasibility of catalyst recycling by simple phase separation is shown in principle.The Rh losses are low in the surfactant system and promising for a technical approach.

One-Pot RAFT Synthesis of Triphenylphosphine-Functionalized Amphiphilic Core-Shell Polymers and Application as Catalytic Nanoreactors in Aqueous Biphasic Hydroformylation

“…Thus, sulfoxantphos keeps the Rh active site in the water phase while the 1-octene substrate remains in the organic phase and in the CCM core. In case of an interfacial effect, the catalytic activity should be high as observed in the presence of other surfactants (40)(41)(42). Note also that the experiment run in the presence of sulfoxantphos yields almost no measurable Rh leaching, giving a first indication that the Rh loss is related to the placement of the metal inside the polymer scaffold.…”

Superior catalyst recycling in surfactant based multiphase systems – Quo vadis catalyst complex?

“…So for the investigation of the catalyst complex distribution only the rhodium amount in the aqueous phase and the middle phase was considered. However, it should be mentioned that minor rhodium leeching into the oil phase was found in the order of 0.1 ppm [18] so that posttreatment of the organic phase would be necessary for complete rhodium recovery.…”

“…7 the influence of different amphiphiles on the distribution of the water-soluble Rh/SX complex is shown. The rhodium content in the oil phase is negligible because of the water-soluble SulfoXantphos ligand as shown in [17,18]. So for the investigation of the catalyst complex distribution only the rhodium amount in the aqueous phase and the middle phase was considered.…”

Hydroformylation of piperylene and efficient catalyst recycling in propylene carbonate

“…23 Homogeneously catalysed hydroformylation affords high selectivity under moderate conditions, however, convenient catalyst separation is a major concern. [28][29][30] Furthermore, there are also thermomorphic solvent (TMS) systems, which consist of solvent mixtures which form a single liquid phase under reaction conditions and a biphasic system after cooling. For example, aqueous biphasic hydroformylation is used in the Ruhrchemie/Rhône-Paulenc process for the production of butyraldehyde from propene.…”