The compound 5 wherein X and X1 are independently selected from the group consisting of {TAIL ~ Cl}, {HEAD ~ CF3CO2}, CH3CO2, CFH2CO2, 3CO, 2CO, 2CO, PhO, MeO, EtO, tosylate, mesylate, and trifluoromethanesulfonate 
The compound 5 wherein X and X1 are independently selected from the group consisting of { TAIL ~ Cl } , { HEAD ~ CF3CO2 } , CH3CO2 , CFH2CO2 , 3CO , 2CO , 2CO , PhO , MeO , EtO , tosylate , mesylate , and trifluoromethanesulfonate
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH