Recently, total synthesis of Palau’amine and its analogues, polycyclic dimeric pyroole-imidazole alkaloid, has been accomplished by Phil, S. Baran and co-workers. These alkaloids contain closely functionalized polycyclic rings and structurally complicated aminal moieties. Generally, the regio- and stereo-selective constructions of aminal moieties are difficult to control, because of its stability and reactivity. In this review, it will be focused on the strategy for the construction of aminal moieties in a later stage of the synthesis, and discussed about his novel and artful synthetic plan making a new wave continually.