The pummerer and the thio‐claisen–type rearrangements of naphtho[1,8‐bc]‐1,5‐dithiocin monooxide and N‐p‐tosylsulfilimine

Naphtho[1,8-bc]-1,5-dithiocin N-p-tosylsulfilimine (8) and monosulfoxide (9) were prepared. On treatment with conc. H2SO4, both the sulfilimine (8) and sulfoxide (9) gave the dithia dication which was converted to the sulfoxide by hydrolysis. The H–D exchange reaction of (8) took place highly regioselectively to afford the monodeuterated (8–D) at the a-position of the N-tosyl group. The Pummerer rearrangement reaction of monooxide (9) with acetic anhydride gave the a-acetoxy derivative by the dication (10b), while a new thio-Claisen rearrangement of sulfilimine (8) t-BuOK in CH2Cl2 gave 2-allyl-naphtho[1,8-bc]-1,5-dithiole. © John Wiley & Sons, Inc.