| Tartalmi leírás: |
A chiral cyclic carbonate, 4-vinyl-1,3-dioxolan-2-one was used as racemic substrate in asymmetric
hydroformylation. The catalysts were formed in situ from “pre-formed” PtCl2(diphosphine) and tin(II) chloride.
(2S,4S)-2,4-Bis(diphenylphosphinopentane ((S,S)-BDPP)), (S,S)-2,3-O-izopropylidine-2,3-dihydroxy-1,4-bis
(diphenylphosphino)butane ((S,S)-DIOP)), and (R)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl ((R)-BINAP))
were used as optically active diphosphine ligands. The platinum-containing catalytic systems provided
surprisingly high activity. The hydroformylation selectivities of up to 97% were accompanied by
perfect regioselectivity towards the dioxolane-based linear aldehyde. The enantiomeric composition
of all components in the reaction mixture was determined and followed throughout the reaction. The
unreacted 4-vinyl-1,3-dioxolan-2-one was recovered in optically active form. The kinetic resolution
was rationalized using the enantiomeric composition of the substrate and the products.
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