Patent ID: 7485759

Claim:
A method of minimizing the production of one or more phosphonium ion ligand degradation products in a process wherein an ester-substituted polyunsaturated olefin comprising an ester of a C 1-8 alkanol or glycerol is hydroformylated with carbon monoxide and hydrogen in the presence of a transition metal-triorganophosphine ligand complex catalyst to form as a product, by-product, or intermediate product an α,β-unsaturated aldehyde which is capable of forming a phosphonium ion ligand degradation product by reaction with the triorganophosphine ligand, the method comprising conducting the hydroformylation process with a triorganophosphine ligand having a ligand cone angle greater than 135°, or having a pKa of less than 8.3, or having both a ligand cone angle greater than 135° C. and a pKa less than 8.3, so as to minimize the formation of phosphonium ion ligand degradation product(s) such that the rate of ligand usage is less than about 0.1 gram ligand per liter reaction fluid per day.