PLATINUM-CATALYZED ENANTIOSELECTIVE HYDROFORMYLATION OF STYRENE - PLATINUM DIPHOSPHINE TIN(II)FLUORIDE CATALYTIC-SYSTEM - A NOVEL ASYMMETRIC HYDROFORMYLATION CATALYST

Enantioselective hydroformylation of styrene was carried out in the pr esence of platinum-containing catalysts. Tin(II) fluoride was used as cocatalyst, giving a catalytic system of unusually high stability. Whe n the optically active diphosphine 2,4-bis(diphenylphosphino)pentane ( BDPP) was used the absolute configuration of the 2-phenylpropanal form ed varied with the temperature used. In dichloromethane the enantiomer ic excess depends strongly on the temperature used. Although the addit ion of 2-diphenylphosphino-pyridine to the catalytic system strongly r educes the catalytic activity, the BDPP-2-diphenylphosphino-pyridine ' 'mixed-phosphine system'' gave 86.7% e.e.