2,2'-Bis(ethoxycarbonyl)-1-O-[(diisopropylamino)(2-cyanoethoxy)phosphino]-3-O-[4,4'-dimethoxy-4''-(1H,1H,2H,2H-perfluorodecyl)trityl]-1,3-propanediol

F-CPR-II CEP allows a combination of fluorous affinity purification with concomitant 5''-phosphorylation, which is especially attractive when synthesizing longmers that will be used in ligase reactions. It may also be utilized as a common handle for fluorous purification, obviating the need to choose a different fluorous phosphoramidite for each different 5''-terminal nucleotide when a 5''-phosphate is tolerated in a particular application.