The presence of {HEAD ~ the catalyst} in {TAIL ~ a mixture} of the substance to be succinylated and succinic anhydride results in significantly greater yield of the desired succinylated product  
in
The presence of { HEAD ~ the catalyst } in { TAIL ~ a mixture } of the substance to be succinylated and succinic anhydride results in significantly greater yield of the desired succinylated product
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH