An efficient protocol of the Ir-catalyzed allylic substitution reaction is reported using N,O-bis (bimethylsilyl]acetamide as a base in the presence of nBu(4)NF as a cocatalyst. The reaction completely proceeded under very mild conditions, and a branched allylated compound that is easy to access via the Tsuji-Trost reaction can be synthesized. The reaction system is practical enough to be applicable for polymer syntheses. The Ir- and Pd-catalyzed allylation polycondensations generally show complementary regio- and stereoselectivities. The Ir-catalyzed reaction is versatile, and a mixed dual regioselectivity such as a branched-linear selectivity on each electrophile can also be achieved.