Access to the New Isoindolo[1,3]benzothiazocinones via the Combination of N-Acyliminium Chemistry and Friedel—Crafts Type π-Cyclization

New racemic and chiral [4,2]- and [3,5]benzothiazocines (4) and (5) in the isoindolinone series were synthesized easily in few steps based on the combination of N-acyliminium chemistry and π-cationic cyclization of acylium ions. The chemoselectivity observed during these processes, particularly in the reduction, the thioalkylation and the cyclization stages, were also discussed.