The invention provides a compound and, tautomeric forms thereof having the formula (I): wherein Rf1 is selected from the group consisting of hydrogen, a straight chain, branched secondary or branched tertiary C1-C20 perfluoroalkyl group optionally containing ether or thioether linkages and C1-C10 perfluoroalicyclic group optionally containing ether or thioether groups; Rf2 is a straight or branched C1-C20 perfluoroalkylene group optionally substituted with ether and thiother linkages; and X is selected from the group consisting of fluorine and formula (II). . The invention also provides perfluoroelastomeric compositions cured with the perfluoroimidoylamidines of the invention as well as combinations of perfluoroimidoylamidines and other curing agents.
