Homogeneous, recoverable hydrogenation catalysts were prepared with use of functionalized ethylene oligomers as ligands. Phosphine groups were introduced onto ethylene oligomers following anionic oligomerization of ethylene. The product polyethylenediphenylphosphine ligands were then exchanged with triphenylphosphine or ethylene ligands to prepare ethylene oligomer ligated rhodium(I) complexes. These Rh(I) complexes had the solubility of polyethylene and dissolved at 90110 C in hydrocarbon solvents but quantitatively precipitated at 25 C. Less than 0.1% of the charged rhodium was lost in each dissolution precipitation cycle. The rhodium(I) complexes so prepared were shown to have about 80% of the activity of tris(triphenylphosphine)rhodium chloride in hydrogenation of various alkenes including 1-octene,2 -cholestene, cyclooctene, cyclododecene, styrene, and -methylstyrene.31P NMR spectroscopy and reactivity studies were used to characterize these catalysts. 1987, American Chemical Society. All rights reserved.
