Ionic liquids in regioselective platinum-catalysed hydroformylation

The regioselective, platinum-catalysed hydroformylation of functionalized a nd non-functionalized olefins was chosen to demonstrate the great potential of room temperature liquid chlorostannate ionic liquids as solvents for ho mogeneous catalysis. The moderate Lewis-acidity of these ionic liquids allo ws the activation of the Pt-catalyst combined with tolerance of the functio nal groups in the substrate. Dissolved in chlorostannate ionic liquids, the Pt-catalyst shows enhanced stability and selectivity in the hydroformylati on of methyl-3-pentenoate (M3P) compared to the identical reaction in conve ntional organic solvents. In the case of 1-octene hydroformylation, a bipha sic reaction system could be realised using the chlorostannate ionic liquid s as catalyst solvents. Besides the catalytic results, a method to determin e the Lewis-acidity of chlorostannate ionic liquids by Sn-119 NMR is presen ted. (C) 2000 Elsevier Science B.V. All rights reserved.