Hydroformylation of olefins

Claim 1

In a hydroformylation process, wherein a C 2-20 monounsaturated alpha-olefin, carbon monoxide, and hydrogen are reacted in the presence of a catalyst comprising a complex of a phosphine ligand and rhodium to produce normal straight chain and iso saturated aldehyde isomers, at a pressure from 100-1,000 psi, the improvement for producing a high normal/iso isomer ratio and without forming sparingly soluble catalyst complexes, which comprises effecting said reaction in the presence of a catalyst comprising a complex of a rhodium compound and chelating phosphine ligand, the chelating phosphine ligand being represented by the formula: R 1 R 2 P A P R 3 R 4 wherein: R 1 and R 3 are alkenyl groups having from 2 to 6 carbon atoms, alkyl groups having from 1 to 6 carbon atoms, hydrogen atoms, phenyl groups, and substituted derivatives thereof; R 2 and R 4 are phenyl groups and substituted phenyl groups; A is an alkenyl group having from 2 to 4 carbon atoms; and (CH 2 ) n wherein n is from 2 to 10 and substituted derivatives thereof; and the molar ratio of said ligand to rhodium is from about 0.6-1.2:1 provided that where A is (CH 2 ) n and n is from 5-10, then the molar ratio is from 1-5:1.