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A chiral ligand, analogous to 2,3-0-isopropylidene-2,3-dihydroxy-l,4-bis(dibenzophospholyl)butane (DBP-DIOP) (5), attached to linear and to cross-linked polymer supports was obtained either by copolymerization of (4R,5R)-2-(p-styryl)-4,5-bis[(tosyloxy)methyl]-l,3-dioxolane (2) with styrene (or with styrene and divinylbenzene) followed by phosphination with lithium dibenzophosphole or directly by copolymerization of (4R,5R)-2-{pstyryl)-4,5-bis[(dibenzophospholyl)methyl]-l,3-dioxalane (4) with styrene (or with styrene and divinylbenzene).Exchange of Pt(II) onto the polymers followed by the addition of stannous chloride gave polymer-supported catalysts which were used for asymmetric hydroformylation of a variety of olefins. Hydroforymlations utilizing the polymer-supported catalysts showed comparable rates and gave nearly the same optical yields as the homogeneous analogue 5. However, lower branched to normal ratios were obtained from the polymer-supported catalysts, especially with those which were cross-linked. The soluble polymer-supported catalyst could be recovered by precipitation with diethyl ether and filtration. Reuse of this catalyst showed no loss in rate or selectivity. Recycling of the cross-linked polymer was achieved by simple filtration with slight loss in rate but no loss in selectivity.

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