Regioselective Access to 2-Iminoimidazolidines via AgF-Mediated Cascade Reactions.

A convergent access to substituted 2-iminoimidazolidines from aromatic amines and N -propargyl S -methylthiourea is developed via Ag(I)-mediated cascade guanylation-cyclization reactions. This method features high regioselectivity, excellent efficiency, and mild reaction conditions. Subsequent deprotection of the Boc ( tert -butyloxycarbonyl) group under acidic conditions provides expedient access to aryl 2-aminoimidazole derivatives in a convenient manner.