An environmentally friendly triphasic catalytic system: Mn(salen) occluded in membranes based on PDMS/PVA

The commercially available Jacobsen catalyst, Mn(salen), was occluded in hybrid polymeric membranes based on poly(dimethylsiloxane) (PDMS) and poly(vinyl alcohol) (PVA). The obtained systems were characterized by UV–vis spectroscopy and SEM techniques. The membranes were used as a catalytic barrier between two different phases: an organic substrate phase (cyclooctene or styrene) in the absence of solvent, and an aqueous solution of either t-BuOOH or H2O2. Membranes containing different percentages of PVA were prepared, in order to modulate their hydrophilic/hydrophobic swelling properties. The occluded complex proved to be an efficient catalyst for the oxidation of alkenes. The new triphasic system containing a cheap and easily available catalyst allowed substrate oxidation and easy product separation using “green” oxidants.

The commercially available Jacobsen catalyst was occluded in hybrid polymeric membranes based on poly(dimethylsiloxane) (PDMS) containing different percentages of poly(vinyl alcohol) (PVA) in order to modulate their hydrophilic/hydrophobic swelling properties The membranes were used as a catalytic barrier between two different phases: an organic substrate phase in the absence of solvent, and an aqueous solution of either t-BuOOH or H2O2.Figure optionsDownload as PowerPoint slideResearch highlights▶ Jacobsen catalyst occluded in PDMS/PVA membranes as a good catalyst for alkenes oxidation. ▶ PDMS/PVA membranes used as a catalytic barrier between reagents avoid the use of toxic solvents. ▶ Hydrophobic/Hydrophilic character of PDMS/PVA membranes can be modulated and permit the use of hydrogen peroxide as a green oxidant. ▶ A cheap and easily available catalyst allows substrate oxidation and easy product separation using “green” oxidants.