Catalytic hydroformylation of styrene-butadiene copolymers

Homogeneous catalytic hydroformylation of styrene-butadiene copolymers was examined with five rhodium catalyst precursors. Under a total pressure of 800 psi H-2 and CO at 40 degrees C, [Rh(COD)(2)]BF4 and [Rh(COD)Cl](2) are more active than HRh(CO)(PPh3)(3), [Rh(COD)dppb]BF4, or [Rh(COD)]BPh4. The hydride HRh(CO)(PPh3)(3) is the most effective of the catalysts at 200 psi and 40 degrees C. Full conversion of polyolefin could be achieved using [Rh(COD)(2)]BF4 or [Rh(COD)Cl](2) as the hydroformylation catalyst. The polyaldehydes, characterized using IR and H-1 and C-13 NMR spectroscopy as well as gel permeation chromatography, are stable under the synthesis gas conditions and formed gels in the presence of air.