A catalyst precursor is provided that is useful in {HEAD ~ the selective hydrogenation} of {TAIL ~ olefinic unsaturation} in polymers or copolymers 
of
A catalyst precursor is provided that is useful in { HEAD ~ the selective hydrogenation } of { TAIL ~ olefinic unsaturation } in polymers or copolymers
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH