A polymeric material is provided comprising a blocked photographically useful group (PUG). The incorporated blocked photographically useful group includes a PUG and a blocking group that is capable of releasing the PUG upon processing the photographic element, wherein the blocking group(a) is capable of reacting with a dinucleophile reagent, and(b) comprises two electrophilic groups that are separated from each other by a substituted atom that enables a nucleophilic displacement reaction to occur with release of PUG upon processing the photographic element in the presence of a dinucleophile reagent, wherein the group that is less electrophilic is bonded directly or through at least one releasable timing group to the PUG.Photographic elements and emulsions including the inventive polymers, and processes for developing an image in the elements, are also provided.